AARST MODEL QUALITY ASSURANCE PLAN
Notes to AARST Users:
This model Quality Assurance Plan (QAP) was developed by AARST for its
membership to provide the beginning of a QAP for companies and individuals involved
in making radon and radon decay product measurements. This document is however
not complete. Each company must expand this QAP with specifics for their company
and device. A standard operating procedure (SOP) for that device can be written as a
separate document that is referenced in the QAP or it can be incorporated directly into
the QAP. If a company has multiple devices then separate SOPs are recommended.
The Quality Assurance Plan (QAP) is the written document which presents, in
specific terms, the objectives, policies, organization, functional activities, and specific
Quality Control (QC) measurements such as duplicates and spikes. The QAP provides
management with a document that can be used to assess whether the planned QC
activities are being implemented.
Quality Assurance (QA) is an umbrella term that includes many activities that
provide the evidence needed to establish confidence that the data obtained are of the
required precision and accuracy.
Quality Control (QC) is the actual measurements that are made for the purpose
of assessing and monitoring data quality, such as blank, spike and duplicate
measurements.
Standard Operating Procedures (SOP) is the written instructions for performing
QA/QC work, particularly the analytical and testing functions. The SOP describes how
the QA officer monitors compliance with the SOP and recommend revisions when
appropriate.
The Quality Assurance Officer (QAO) is a vital link in the success of a QA
program. The QA Officer is generally responsible for
*
writing and revising the QA procedures so they are consistent with current
state and federal guidelines or requirements as well as assuring that they
are clear, thorough and practical.
*
ensuring the implementation of the QA Plan, including making written and
oral recommendations to management regarding data quality;
*
developing the procedures for chain-of-custody, statistical analyses, data
verification, training in QA procedures, and whatever else is necessary to
properly implement the QA Plan;
page 1 of 2
The objective of quality assurance is to maintain a quality measurement program
and to document that quality. In addition, a QA program adds greatly to an operators
understanding of the methods they use and provides early detection of problems so
that they can be rectified quickly. A testing company that has inadequate QA records to
document the validity of measurements, especially those made during real estate
transactions, may have serious liability potential.
1.
The text that appears in italics (as is this note) are notes to you, and should be deleted
prior to final printing. Some of the italics may precede sections which are only applicable to
some measurement methods and both the italics text and some of the text that follows should be
deleted.
2
This model QA plan is for testing companies and individuals and not for device
manufacturers or charcoal or alpha track laboratories.
3.
The text enclosed in brackets < > is replaced by the appropriate information about your
organization and services.
4.
Use as specific information as possible, including names of people and model names of
equipment. The QA Plan is a "living document" that is frequently revised and referred to. Even
handwritten changes can be used on a temporary basis, if they are initialled, dated, and the
responsible officials initial and date their signatures on the signature page.
5.
This QA Plan can contain all the detail in a Standard Operating Procedure (SOP) if the
QAP refers to only one type of device. For multiple devices a single QAP can refer to separate
SOPs written for each measurement method. The SOP describes all the detector operating
procedures in sufficient detail to serve as a reference for training new employees. References to
a SOP in the QA Plan should list the detector the SOP is written for and the latest revision date.
(The EPA provides a brief description of what a SOP should contain in the EPA Homes
Protocols [EPA 1993], in Section 4.5, page 4-8).
6.
Attached to the QA Plan, as an Appendix, are copies of blank forms used routinely, such
as log entry forms, customer instruction sheets or reports.
7.
This plan is a guide to be molded to your needs; much more information needs to be
added; for some organizations some information may be more appropriate in different sections,
and in other cases some of these sections may not be appropriate. This model QAP needs to be
modified in order to include more than one detector type.
This model Quality Assurance Plan was written by:
Melinda Ronca-Battista
14642 South 25th Place
Phoenix, AR 85044
and
Bill Brodhead
2844 Slifer Valley Rd.
Riegelsville, PA 18077
page 2 of 2
(602) 759-1544
(610) 346-8004
page 3 of 2
<Detector Name>
QUALITY ASSURANCE PLAN
for
<Company Organization (if applicable)>
<Company Name>
<Address>
<Phone #>
Prepared by
<Preparer's Name>
<Title>
<Date>
Revision Date: <Date of most recent revision of any page herein>
Signatures and Dates:
______________________
Quality Assurance Officer
< Name >
____________________________
President or Principal Investigator
< Name >
___________________________________
Individual Operator or Laboratory Director
< Name >
Note: Use these or applicable titles, complete names, signatures, and date the signatures.
These signatures represent the awareness of, approval of, and responsibility for
this plan of all persons who have significant responsibility for ensuring that the
provisions of this plan are implemented.
CONTENTS
1.0
INTRODUCTION & DISTRIBUTION LIST ........................... Rev 1 - 6/10/94
1.1 Introduction ...................................................................................... 1-1
1.2 Distribution List ................................................................................... 1-1
2.0
DESCRIPTION OF OPERATIONS ....................................... Rev 1 - 6/10/94
2.1 Description of Equipment ................................................................. 2-1
2.1 Operation Description ....................................................................... 2-1
3.0
ORGANIZATION & RESPONSIBILITIES.............................. Rev 1 - 6/10/94
4.0
MEASUREMENT PROCEDURES ........................................ Rev 1 - 6/10/94
4.1
Measurement Definitions ................................................................. 4-1
4.2
Measurement Types ........................................................................ 4-2
4.3
Guidelines, State Regulations, & Federal Protocols ........................ 4-2
4.4
Radon Survey by Test Technician ................................................... 4-3
4.5
Measurement Location ..................................................................... 4-3
4.6
Number of Measurements ................................................................ 4-4
4.7
Measurement Exposure Time .......................................................... 4-4
4.8
Detector Non-Interference ................................................................ 4-5
4.9
Closed House Conditions ................................................................. 4-5
4.10 Informing Client about Test Conditions ............................................ 4-6
4.11 Safety ............................................................................................... 4-6
4.12 Minimum Test Condition Verification ................................................ 4-6
4.13 New Construction Test Conditions ................................................... 4-7
Section No.i
Rev No. 1
Date: 6/10/94
Page ii of iii
5.0
CHAIN of CUSTODY & DOCUMENTATION ........................ Rev 1 - 6/10/94
6.0
ANALYTICAL PROCEDURES .............................................. Rev 1 - 6/10/94
7.0
CALIBRATION PROCEDURES ............................................ Rev 1 - 6/10/94
8.0
DATA CALCULATION, VALIDATION, & REPORTING ........ Rev 1 - 6/10/94
8.1 Data Calculation ................................................................................ 8-1
8.2 Data Validation .................................................................................. 8-1
8.3 Data Reporting .................................................................................. 8-1
8.4 Maintaining Records ......................................................................... 8-2
9.0
INTERNAL QUALITY CONTROL.......................................... Rev 1 - 6/10/94
9.1 Routine Instrument Checks & Preventive Maintenance ................... 9-1
9.2 Routine Spiked Measurements made to Assess.............................. 9-1
9.2 Cross Checks made to Assess Bias ................................................ 9-2
9.3 Duplicate Measurements made to Assess Precision ....................... 9-3
9.4 Exposure of Field Blanks for Passive Detectors .............................. 9-4
10.0
QUALITY ASSURANCE OBJECTIVES &
PROCEDURES for ASSESSING PRECISION & BIAS ......... Rev 1 - 6/10/94
10.1 Monitoring Bias ............................................................................ 10-1
10.2 Monitoring Precision ..................................................................... 10-2
11.0
QUALITY ASSURANCE AUDITS &
MANAGEMENT REPORTS .................................................. Rev 1 - 6/10/94
12.0
CORRECTIVE ACTION ........................................................ Rev 1 - 6/10/94
13.0
QUALITY ASSURANCE TRAINING ..................................... Rev 1 - 6/10/94
Section No.i
Rev No. 1
Date: 6/10/94
Page iii of iii
14.0
REFERENCES ...................................................................... Rev 1 - 6/10/94
15.0
EXHIBITS ............................................................................ Rev 1 - 6/10/94
APPENDIXES
1.0
INTRODUCTION AND DISTRIBUTION LIST
1.1
Introduction
This Quality Assurance Plan QAP is consistent with the guidance issued by the U.S.
Environmental Protection Agency (EPA Interim Guidelines for Preparing QA Plans [EPA
1980]; EPA Requirements for QA Project Plans [EPA 1992a]). This Plan is formatted in
a way that allows <organization name> staff to reference easily pertinent portions of this
document. The 16 elements recommended by the EPA (EPA Interim Guidelines for
Performing QA Plans [EPA 1980]) are all included although some have been combined.
For example, corrective actions are included with each section for which it is
appropriate, instead of discussing all corrective actions in a separate section. The
nomenclature used in this QAP is appropriate for the operations of <organization
name>, and every effort has been made to maintain consistency with the latest EPA
guidance (QA Guidance for RMP Participants [EPA 1993 draft]).
1.2
Distribution List
This report reflects current operations, and therefore is often updated and revised.
The QA Officer has responsibility for incorporating changes, and ensuring that the
changes are reviewed and approved by the management, as indicated by their dated
signatures on the signature page. After significant revisions, revised copies of this QAP
are distributed to the following key personnel:
<QA officer>
<Lab director>
<Co. manager or Co. president>
<Names of other Co. employees>
2.0
DESCRIPTION OF OPERATIONS & EQUIPMENT
2.1 Operation Description
<Organization name> performs measurements of <radon and/or radon decay
product> concentrations for <residences, commercial buildings, and schools>. In
general, the number of measurements performed ranges from < > to < > per month.
The staff consists of <staff names and titles>, and <QA officer name>, the Quality
Assurance Officer. The <laboratory or office> is located at <address>.
2.2 Description of Equipment Used
<This organization> measures <radon and/or RDP> using <detector name>.
Note: This section includes specific model numbers, serial numbers, if appropriate, of all the
equipment used. Include a brief description of the detectors and how they function. If a
laboratory is used for analysis, or if analyses are conducted in different locations, this is briefly
described here.
3.0
ORGANIZATION & RESPONSIBILITIES
The following <company name> employees have key responsibilities in the
production of <radon and/or decay product> measurement operations.
Note: Describe the organization, with names, titles, and functions. The responsibilities of each
person or department is briefly described. A chart may be useful. Two important components
are the quality control procedures and how the Quality Assurance Officer fits into the
organization. If the QA Officer makes recommendations, to whom are they made? Who has
responsibility for implementing the changes? Who is responsible for documenting changes in the
Standard Operating Procedures (SOP) and/or in the QA Plan? Who has responsibility for
training a new employee or retraining employees in the case of changes in procedures?
4.0
MEASUREMENT PROCEDURES
This section covers the procedures that are followed to ensure that the
measurements are made in appropriate locations and test conditions consistent with
EPA recommendations and clients' needs.
4.1
Measurement Definitions
Client - Person, persons, or businesses who have contracted with <company name> to
perform a radon survey in a dwelling involved in a real estate transaction.
Long-Term Measurement - Any radon or radon decay product measurement that is
acknowledged as appropriate and acceptable in the EPA Measurement Protocols and
has a duration of more than ninety days. Long term measurements are normally made
using <list long term device that your company uses> exposed continuously over the
exposure period. A one year follow-up measurement can also be made by averaging
the results of a series of 3 or more equally spaced short-term (2 to 7 day)
measurements taken throughout the year under normal living house conditions. Long
term measurements for dwellings involved in a real estate transfer are duplicate
measurements in the lowest tested area.
Occupant - A person living in a dwelling who may or may not be the owner of the
dwelling and is responsible for the dwelling.
Primary Measurement - A radon or radon decay product measurement that provides
an averaged concentration over the exposure period. The detector is be located as
specified in the EPA Measurement Protocols. The detector is be operated in
accordance with the recommendations of the detector manufacturer or supplier. The
detector exposure time is not less than the recommended time as specified in the EPA
Measurement Protocols, the Citizen's Guide or any EPA real estate testing protocols.
The detector is not exposed for fewer than 48 continuous hours.
Radon Survey - The process of a test company following the guidelines of this QAP
and making one or more primary measurements to sample and analyze the air in a
dwelling, either passively or actively, so as to measure the radon or radon decay
product concentration during the test period in the areas being sampled.
Responsible Individual - This refers to the person or persons responsible for assuring
that the test conditions required by this QAP are being followed during a radon survey.
This responsible individual does not necessarily have to be the owner of the dwelling.
Short-Term Testing - Any radon or radon decay product measurement that is a
primary measurement and has a duration of from two to ninety days.
Section No.4
Rev No. 1
Date: 6/10/94
Page 2 of 7
Test Technician - The person responsible for placing and retrieving the <radon or
radon decay product> detector. This person may be either the owner, employee or
subcontractor of the test company. The test technician abides by all the requirements
of the state in which the test is being conducted. The test technician is under the
supervision of <company name>. The test technician has, as a minimum, attended a
state or federally approved radon testing course that fulfills any necessary educational
requirements for state certification in the state in which the test is being performed, or
has been continually employed for one year as a test technician under the supervision
of a state certified company. The test technician has obtained RMP listed individual
participant status or equivalent status with a certifying state agency.
4.2
Measurement Types
The EPA defines three types of radon gas measurements; initial measurement,
follow-up measurement and post-mitigation measurement.
An initial measurement is of a relatively short-term duration (usually 2 to 7 days) to
detect a radon problem in a home. Short term tests must be carried out under closedhouse conditions and in the lowest lived-in area of a house or lowest area suitable for
occupancy if the house is involved in a real estate transaction. If the result of the initial
measurement done under closed house conditions is below 4 pCi/L, a follow-up test is
not necessary.
A follow-up measurement is a measurement made to verify and characterize a
radon problem as indicated by a previously made short term measurement value at or
above 4 pCi/L. In general, the higher the initial measurement, the sooner the follow-up
measurement is made and the shorter the exposure period in order to minimize the
health risk to the residents; viz., (1) if the initial test result was between 4 and 10 pCi/L,
a long term measurement lasting up to a full 12 months is recommended, (2) if the
initial measurement was greater than 10 pCi/L, a short term measurement is
recommended.
A post-mitigation measurement is a short term measurement made in the lowest
lived-in area of the dwelling or the lowest level suitable for occupancy if the dwelling is
involved in a real estate transaction. The test must not be started sooner than 24 hours
after the installation of the radon system. The test must have 24 hours of closed house
conditions before the start of the test and closed house conditions during the test.
4.3
Guidelines, State Regulations, and Federal Protocols
Federal or state regulations or certification requirements in the state in which the
radon survey is being performed is followed for measurements performed in that state.
All applicable existing laws, including but not limited to statutes, ordinances and
Section No.4
Rev No. 1
Date: 6/10/94
Page 3 of 7
regulations, are complied with by <company name> and <company name> test
technicians in all locations in which the survey is being conducted. The test company
does not offer or perform any act or service contrary to law.
4.4
Radon Survey by Test Technician
During a radon survey of a dwelling involved in a real estate transfer, primary
measurement placement and retrieval of the detector(s) is only performed by a test
technician as defined in 4.1. The test technician ensures that the client has obtained
the test technician's RMP identification number <and/or state certification number if
applicable>.
4.5
Measurement Location
Measurement locations are chosen according to the following criteria.
o
The locations are consistent with the guidelines set forth by the EPA (EPA
Device Protocols [EPA 1992], Section 1.2.3, page 1-3). These guidelines are
paraphrased in the instructions to clients.
o
The purpose of the measurement and type of building dictates the measurement
strategy and location; specific EPA guidance is used for measurements in
homes (EPA Homes Protocols [EPA 1993]), for real estate transactions (EPA
Buyer's and Seller's Guide to Radon [EPA 1993a]), and in schools (EPA Radon
Measurements in Schools [EPA 1993b]).
o
Specific needs or requests of clients are considered.
The following general criteria are to be used in selecting the location of a detector
within a room.
o
A location must be selected where the detector is not be disturbed during the
measurement period.
o
The detector must not be placed near drafts caused by HVAC vents, windows,
and doors. Avoid locations near excessive heat, such as fireplaces or in direct
sunlight.
o
The detector can be suspended from the ceiling if it is within the breathing zone
(6' to 8' high) or placed on a shelf or table at least 50 centimeters (20 inches)
above floor level and with its top face at least 10 centimeters (4 inches) from
other objects.
Section No.4
Rev No. 1
Date: 6/10/94
Page 4 of 7
o
o
o
The detector must not be placed within 30 centimeters (12") of the outside walls
of the house or within 90 centimeters (36") of any opening in the outside walls
such as windows.
Nothing must impede air flow around the detector.
In general, kitchens, bathrooms, laundry rooms, root cellars, garages, crawl
spaces, or sumps are not suitable measurement locations.
4.6
Number of Measurements
In order to determine comprehensively a dwelling's potential to have elevated radon
levels, a radon survey has a minimum of one primary measurement in each lowest
structural area suitable for occupancy. An example of the required test areas would be
a split level style of dwelling with a finished basement, a slab on grade room, and a
room over a crawl space. Each of these three separate lowest structural areas would
require one primary measurement. The measurement placement conforms to the
current EPA measurement protocols for radon measurements.
To ensure that the radon survey is a valid representation of the radon levels, <either
an active detector or a duplicate (simultaneous) measurement made with two detectors,
side by side or a measurement followed by a second measurement (sequential) is
made>.
If sequential measurements are made, then the results of the first
measurement are not revealed until the completion of the second measurement. The
requirement to use <an active detector, or simultaneous measurement or sequential
measurement>, only pertains to the measurement taken in the lowest level of the
dwelling.
4.7
Measurement Exposure Time
The measurement exposure time is a minimum of 48 hours.
Short-term
measurement exposure time should be in increments of 24 hours plus or minus 1 hour
for each day of exposure in order to minimize the effect of diurnal variations. This
means that a three-day test should be exposed from 69 to 75 hours. The exposure
time is not be less than the manufacturer's or supplier's recommendations.
If the radon survey is to be a long-term measurement, closed-house conditions need
not be maintained. The test company should, however, recommend to the owner or
occupant of the dwelling that at least half the test period should be during the season
that the dwelling is most likely be operated with closed-house conditions and that
reasonable closed-house conditions should be maintained during the test period so that
the results of the test are more accurate indicators of the yearly average. Long term
measurements for dwellings involved in a real estate transfer are duplicate
measurements in the lowest tested area.
Section No.4
Rev No. 1
Date: 6/10/94
Page 5 of 7
4.8
Detector Non-Interference
Test Technicians should not initiate a measurement if the occupant is moving or is
planning remodeling, changes in the heating, ventilating and air conditioning (HVAC)
system, or other modifications that may influence the radon concentration during the
measurement period. <Detector name> should not be deployed if the occupant's
schedule precludes termination of the measurement at the appropriate time.
The testing device is not be moved, covered or have its performance altered during
the radon survey by anyone. Examples of performance alteration would be covering
the detector, moving it to another location during the test period, or opening windows
during a short-term test.
The responsible individual is requested to sign a non-interference agreement that
indicates a knowledge of the testing conditions of this QAP and a willingness to
cooperate in maintaining the required test conditions. If such an agreement cannot or
will not be signed by the responsible individual, <company name> indicates in the
Report why the signature was not obtained.
Appendix A is an example of
Non-Interference Agreement.
<List other tamper methods used by your company.>
4.9
Closed-house Conditions
The weather and building ventilation conditions prior to and during the measurement
are in accordance with the guidelines set forth by the EPA (Device Protocols [EPA
1992], Section 1.2.2, page 1-2). These guidelines are paraphrased in the instructions
to clients.
Closed-house conditions require that all the windows are kept closed. External and
any basement to first floor doors are closed except for normal momentary entering and
exiting. Structural openings due to disrepair or structural defects that allow a significant
amount of ventilation is repaired to correct their condition before initiation of closedhouse conditions. All exterior windows and doors are inspected by the test technician
at the placement and retrieval of the detector. The test technician walks around the
outside of the house to inspect for closed-house condition.
Heating, air conditioning, and heat recovery ventilators can be operated normally.
Operation of dryers, range hoods, and bathroom fans should be kept to a minimum.
The responsible individual, however, should be informed that overuse of an appliance
that exhausts air may influence the final readings.
Section No.4
Rev No. 1
Date: 6/10/94
Page 6 of 7
Whole house fans are not operated. Portable window fans are removed from the
window or sealed in place. Window air conditioning units are only operated in a
recirculating mode. If the dwelling contains an air handling system, the air handling
system is not set for continuous operation unless the air handling equipment is
specifically used for radon control and labeled as such.
Fireplaces or combustion appliances are not be operated unless they are the primary
sources of heat for the dwelling. Ceiling fans, portable dehumidifiers, portable
humidifiers, portable air filters and window air conditioners are not operated within
twenty feet of the detector. Closed-house conditions are maintained for twelve hours
prior to the start of the radon survey, if the test period is four days or fewer in duration
and recommended for tests up to seven days long. <Company name> inquires with the
responsible individual to determine if closed-house conditions have been maintained for
the twelve hours prior to the start of the test.
The test technician takes due and proper care in obtaining closed-house conditions
during short-term testing in order to increase measurement reproducibility. If at the
initiation of the test, the test technician discovers or visually observes that closed-house
conditions were not maintained, then the radon survey is not initiated until twelve hours
of prior closed-house conditions have been maintained or the radon test period is
extended to four days or more with an appropriate detector after closed-house
conditions are initiated.
4.10
Informing Client about Test Conditions
<Company name> makes reasonable efforts to determine who is the responsible
individual for the dwelling during the test period. Before any primary measurements are
begun, the responsible individual is informed or attempted to be informed about the
requirements of and the need for closed-house conditions as well as all other conditions
for which they are responsible. A copy of the EPA document, "Home Buyers and
Sellers Guide to Radon" should be given to each client.
In order to inform occupants of the dwelling about the test and the conditions of the
test, a "Radon Survey in Progress" notification form with the conditions of the test
stated on the notification, is posted upon initiation of a short- term test in a conspicuous
location of the dwelling. Appendix B is an example of a Radon Survey in Progress
notification form used by <company name>.
4.11
Safety
The test technician should not enter any area or perform any test that would damage
property or risk the test technician's own or another's safety. If it is known that
closed-house conditions are detrimental to the health of the occupants, then the radon
survey using a short-term test is not done.
Section No.4
Rev No. 1
Date: 6/10/94
Page 7 of 7
4.12
Minimum Test Condition Verification
<Company name>'s minimum requirements for verifying test conditions is fulfilled by
the following: informing the responsible individual of the test conditions, obtaining or
attempting to obtain a signed non-interference agreement, conducting a visual
inspection of the dwelling upon placement and retrieval of the detector, and posting a
Radon Survey in Progress notification form. This QAP does not require the test
technician to be responsible for inspecting for closed-house conditions 12 hours before
the start of the test or between placement and retrieval of the detectors.
4.13
New Construction Test Conditions
Newly constructed dwellings are tested in accordance with this QAP. The following
items, if such items are part of the completed dwelling, are installed and completed
before the radon survey is initiated: all insulation, all exterior doors, all windows, all
fireplaces and fireplace dampers, all heating appliances, all ceiling coverings, all interior
trim and coverings for the exterior walls, all exterior siding, weatherproofing and
caulking. If <company name> knows construction work, which will likely affect the test
results, is to be done inside the dwelling during the test period, then the <company
name> schedules the test during a time when such interference is less likely to take
place.
5.0
CHAIN OF CUSTODY AND DOCUMENTATION
Note: This section includes the record keeping procedures, with a list of the information to be
gathered with each measurement; copies or descriptions of the logbooks and forms used
(reference copies in appendix); the record keeping procedures for maintaining records of QA
practices and QC measurements, including calibration results, background measurement results
and any changes in operators, materials, or procedures. Logbooks should be bound, and
records made in pen. Every entry includes the name of the person making the entry and the date.
Chain of custody for each <detector name> includes documenting the exposure
location, times and dates in/out, and persons responsible for the detectors prior to,
during and after their exposure, up to their <analysis or shipment to the analysis
laboratory>. <Name and/or previously listed title> is responsible for ensuring that this
information is properly recorded for each measurement.
It is important that enough information about each measurement be recorded on the
proper forms by the Field Technician or homeowner who deploys the detector (see
"Operating Instructions" form in Appendix <list detector instruction sheet appendix
number> and by the Laboratory Director in the permanent "Detector Placement Log
Book." This data is important in case further interpretations and measurements are
required at a later date.
The information called for on the data form included with the detector (Appendix <list
appendix number>) must be accurately completed by the <homeowner or field
technician> when the detector is placed and/or retrieved. The detector serial number is
recorded by <lab director> on a separate log sheet and the <homeowner or Field
Technician> records a description of the location in the house where it was placed. The
detector is not to be relocated during the measurement period; however, if it is
necessary to do so (e.g., during a long-term test), the Field Technician should note the
new location on all relevant log sheets.
The information to be logged must include:
o
Address of measurement client and building measured.
o
The start and stop, date and times of each measurement.
o
The detector type and identification numbers.
o
Whether the homeowner has agreed in writing to abide by the closed house
conditions (if applicable) throughout the test period and twelve hours before the
test.
o
Exact locations of the detector.
Section No.5
Rev No. 1
Date: 6/10/94
Page 2 of 2
o
Other easily gathered information that may be useful, such as the type of house,
type of heating system, condition of crawl space vents.
Note: This next section is appropriate only for users of those methods that involve analysis (e.g.,
primary organizations).
6.0
ANALYTICAL PROCEDURES
The measurement procedures recommended by EPA (Device Protocols [EPA 1992])
and <detector manufacturer > are followed. These include <list basic steps used to
obtain a measurement>. <If separate SOP is written then it can be a brief description
here with reference to the specific SOP.>
Note: Include specific information on corrective action, which is what to do and who is
responsible when something in the analysis goes wrong or is not as expected. (e.g., background
of active monitor is approaching the activity of the air to be sampled.)
Note: This section is not relevant for organizations that use passive detectors that have analysis
equipment that is calibrated by the manufacturer or another company.
7.0
CALIBRATION PROCEDURES
Calibration of the <primary detector name(s)> is conducted prior to initiating field
measurements and at least every 12 months in accordance with the following
procedures.
Note: This section briefly describes the calibration process, including specific information, such
as the pre-calibration performance checks (background, high voltage adjustment, flowrate, etc.)
and adjustments, as well as the range of radon/RDP exposure the detector is exposed to.
Factors which may not be always achieved can be stated as goals. If instruments or systems are
calibrated by the manufacturer or other laboratory, their procedures for calibration can be
referenced (by title and date). The documentation of the calibration facility, where exposures
are performed, should be attached to the QAP or referenced. This documentation indicates the
successful participation in federal intercomparison exercises or other traceability to a federal
laboratory standard.
8.0
DATA CALCULATION, VALIDATION, AND REPORTING
Note: This section includes a description of the methods by which the readings produced by the
instrument or detector are recorded, transformed to radon concentrations, and reported to the
client.
8.1
Data Calculation
Note: This section is not relevant for secondary organizations that receive results from an
independent laboratory. Primary organizations that are responsible for producing the result
reported to clients list here the formulas and procedures used to obtain the <radon or RDP>
result.
8.2
Data Validation
Note: This section describes the procedures used to avoid transcription errors and to spot-check
reports to clients for accuracy.
<In this section describe the procedures for hand-calculating entries for errors in
calculation, transcription, or in the computer database. The procedures should state
how often, how many and by whom entries are checked; the frequency should be at
least semi-annually, and after any change in procedure, personnel, or equipment.> A
transcription error rate greater than < 5 > significant errors in 100 fields is cause for
notification of the QA Officer, who investigates and recommends re-entry of data if
necessary.
8.3
Data Reporting
Final results are reported in units of <pCi/L or WL>, in the format provided by the
<Company name> test report (see sample report in Appendix <reference appendix #>).
The information furnished to clients in the test report follows the recommendations
made by EPA (Homes Protocols [EPA 1993]). Values are reported to <one figure after
the decimal for radon concentrations, and to three figures after the decimal for radon
decay product concentrations>. <Name or listed title> is responsible for checking the
accuracy and completeness of the test reports before they are sent to the client.
The Report is in writing and either mailed first class, faxed or hand delivered to the
client within five business days after the results are obtained by the test company. The
report contains the following.
o
Address of measurement client and building measured.
o
o
The start and stop, date and times of each measurement.
The detector type and identification numbers.
Section No.8
Rev No. 1
Date: 6/10/94
Page 2 of 3
o
Whether the homeowner has agreed in writing to abide by the closed house
conditions (if applicable) throughout the test period and twelve hours before the
test.
o
Exact location of the detector.
o
Test Technicians EPA RMP or equivalent state certification numbers .
o
Any required statement by the state, EPA or this QAP.
o
Observed status of mitigation system if applicable.
o
Any observed structural openings, such as crawl space vents.
o
Any observed deviations from required test conditions.
The test report includes an interpretation of the measurement results that uses the
EPA "A Citizens Guide to Radon (Second Addition)" and/or the "Home Buyers and
Sellers Guide to Radon" as its source.
The measurements are reported in units that are appropriate to the measurement
method. Any test report that converts measurement results to the unit of another
product discloses, as a minimum, the limitations and the possibility for variations of
such conversion as well as the equilibrium ratio used to make that conversion.
The Report should describe the general limitations of the test such as the following
statement:
There is an uncertainty with any measurement result due to statistical variations and
other factors such as daily and seasonal variations in radon concentrations due to
changes in the weather and operation of the dwelling as well as possible interference
with the necessary test conditions that may or may not influence the results.
All test results include a statement which recommends that the dwelling be retested
in each of the following cases whether or not the dwelling has been mitigated:
o
o
o
o
o
o
Occupancy by a new owner
Two years since the previous test
A new addition is added
An alteration is made that could change the ventilation pattern
Major cracks or penetrations occur in the foundation walls or slab
Significant nearby construction blasting or earthquakes occur
Section No.8
Rev No. 1
Date: 6/10/94
Page 3 of 3
o
o
Changes are made or happen to an installed mitigation system
Occupation of a ground contact area that was not previously tested
8.4
Maintaining Records
Radon and radon decay product measurements are a radiation exposure
measurement. Because the effects of radiation exposure may not become apparent
until many years have passed, measurement data should be maintained permanently.
9.0
INTERNAL QUALITY CONTROL (QC)
This section describes specific procedures for four types of internal quality control
(QC) checks, measurements and procedures:
a)
Routine instrument performance checks
b)
Analysis of measurements made to assess relative bias
c)
Analysis of duplicate measurements made to assess precision.
d)
Laboratory analysis of blank field detectors
9.1
Routine Instrument Performance Checks and Preventive Maintenance
Specific procedures relevant to quality assurance include: <Here describe those
procedures conducted to check the quality of the measured result. For some methods
this may be minimal, for other detectors more extensive. For example, routine active
instrument performance checks may consist of checking the battery, pump flow rates,
and filters, etc.> For each type of check, the following procedures are followed.
<Name> is responsible for conducting the following checks.
The performance checks are conducted <every measurement, once a week>.
The results are documented in <where>, after each performance check.
The numerical limits are that <any measured parameter (e.g., max/min flow rate,
maximum background) and the procedures for corrective action if the results of
the checks are not within these limits>.
This documentation is <periodically> reviewed by <QA officer> and <Name or
listed title> is responsible for any additional investigation and/or corrective action.
Note: Include the passive or active method used below in 9.2 and delete the other method.
Passive Method
9.2
Spiked Measurements Made to Assess Bias
Any consistent bias of the <detector name> method is evaluated by exposing the
detectors to a known concentration (spiked). Spiked measurements made to assess
bias are made at a frequency of at least 3 per 100 measurements (e.g., if approximately
300 measurements are estimated for the next 6 months, then at least nine spiked
Section No.9
Rev No. 1
Date: 6/10/94
Page 2 of 4
measurements are made at a radon calibration chamber.) The passive detector is
exposed in a radon chamber that intercompares its results with an EPA or DOE radon
chamber at least every six months or the passive detectors are carefully exposed by
an independent company in a known volume chamber that contains a NIST
radium standard and NIST approved procedures for such an exposure are used.
The QA officer is responsible for ensuring that <chamber facility name> used by
<Company name> provides documentation of its own frequent and regular successful
participation in EPA and/or U.S. DOE intercomparison exercises or traceability to a
NIST standard. <Chamber facility name> makes available its procedures for stringent
internal QA including documentation of "traceability" to the EPA, NIST or U.S. DOE
laboratory standards. A copy of the most recent federal intercomparison records of
<chamber facility name> is on file.
Note: It is recommended that chamber blanks and blanks to determine any exposure in transport
(if relevant) be considered part of the spike procedure.
The <detector name>s to be exposed in the calibration chamber are selected from
the stock of detectors by the QA Officer. Specifications for spiking the exposure of the
detectors is made by the QA Officer, in written form, directly to the calibration facility.
Note: If relevant the radon chamber average gamma background, relative humidity or
temperature is requested.
Results of the analysis of spiked samples are evaluated by the QA Officer following
the procedures described in Section 10.1 and recorded on a control chart as shown in
Exhibit 1 to determine any consistent bias in the results and to identify the need to
contact the detector manufacturer about making corrections.
Active Monitor
9.2
Crosschecks Made to Assess Bias
Any consistent bias shown by the instrument(s) is evaluated by performing regular
crosschecks with a recently calibrated (see Section 7.0) instrument.
These
crosschecks are performed during the 12-month interval between calibration, and
approximately six months after calibration, so that no more than about six months
elapses between either a calibration or a crosscheck. Refer to section 7.0 for
calibration procedures. Crosschecks are conducted with the following procedures.
a)
<list the detector manufacturer's instructions regarding checking the unit for
background and conducting instrument performance checks (use instructions
from the detector user manual)>
Section No.9
Rev No. 1
Date: 6/10/94
Page 3 of 4
b) The monitor is exposed in an environment that averages, if possible, greater
than 4 pCi/L for a minimum of 48 hours directly adjacent to a recently calibrated
active monitor (not necessarily the same type or model, but one that produces
results in the same units and has been calibrated within the last 30 days).
The environment where the monitors are compared is, if possible, chosen for its
<radon or RDP> stability, and in an area where radon levels are considerably
greater than each unit's lower limit of detection. Both units measure over the
same time interval, although the recently calibrated monitor can have the
capability to measure in shorter intervals. The initial four hours of data is not
used in the calculation.
The results for each monitor are averaged and
analyzed in terms of percent difference (%D), as described in Section 10.1.
The results of crosschecks are analyzed following the procedures described in
Section 10.1.1 and recorded on a control chart as shown in Exhibit 2. The QA Officer is
responsible for checking the results of these crosschecks and determining the
maximum amount of disagreement (upper bounds of agreement) between devices.
<The upper bound may be based upon a sSTD as calculated from the control chart or
may be a standard level specified as a percent difference (%D). Refer to exhibit 2 and
4. For example, corrective action might be required if the devices do not agree to within
15 %D.>
9.3
Duplicate Measurements Made to Assess Precision
The precision of the measurement method is evaluated on an ongoing basis through
the use of duplicate measurements.
Note: Include the passive and/or active method used below and delete what is not relevant.
Passive Duplicate:
Passive duplicates are defined as identical detectors placed approximately four
inches apart. Every tenth measurement receives two detectors instead of one, until at
least 25 pairs (50 total detectors) are placed each month. Duplicate results are logged
in the duplicate file as Result A and Result B. To ensure that some radon
concentrations greater than 4 pCi/L are measured by duplicates, it may be necessary to
place duplicates occasionally in locations of elevated radon concentrations (e.g., staff
person's crawl space). If duplicate pairs are to be exposed by the homeowner, test
instructions clearly explain how this is to be done.
Note: Occasional use of nonidentical detectors for comparison may help identify a bias
in either measurement system under field conditions and may be very useful, but these
measurements are not considered true duplicates.
Section No.9
Rev No. 1
Date: 6/10/94
Page 4 of 4
Active Duplicate:
Active duplicates are defined as measurements made with the same type of
instrument over identical time periods with air intakes adjacent. When two monitors are
available at the same location, side-by-side measurements in approximately 10 percent
of the total number of measurements, or up to 25 each month is made. If only one
similar active monitor is available, one out of every 10 measurements is checked with a
second device (not necessarily a "recently-calibrated" active instrument but any passive
or active device that is RMP listed) placed adjacent to the active device for the same
time period. Organizations with only one available monitor are not able to assess precision.
Precision of a single instrument can only be roughly estimated from the analysis error provided
by the detector manufacturer, (the manufacturer can measure precision because they have
multiple units available, although they sometimes use counting statistics which can be
misleading). Precision error for organizations with only one monitor is therefore
referenced from information provided by the manufacturer.
The results of duplicates are analyzed following the procedures described in Section
10.2.1 and recorded on a control chart as shown in Exhibit 3. The QA Officer is
responsible for checking the results of these duplicates and determining upper bounds
for agreement between devices. <The upper bound may be based upon a sigma level
as calculated from 20 in control duplicate pairs, (reference exhibit 3), or may be a
standard level specified as a relative percent difference.>
Note: Section 9.4 is for passive methods:
9.4
Exposure of Field Blanks for Passive Detectors
The EPA recommends that field blanks for passive detectors number approximately
five percent of the detectors deployed. At least <5> per <100 measurements> are set
aside as blanks and not exposed. The location and length of storage of blanks is
determined by the QA Officer. Blanks are, if possible, shipped and handled as other
exposed detectors. The results of these blanks are assessed by the QA Officer. If any
blank result is significantly above the LLD, the QA Officer assesses the cause for the
elevated reading and/or contacts the analysis laboratory. If appropriate, as determined
by the QA Officer in consultation with the analysis laboratory, the results of the blanks
are subtracted from the results of the exposed detectors.
Note: This QA Plan is not designed to encompass the range of procedures (including laboratory
blanks) faced by an analysis laboratory for ATD or charcoal devices; routine assessment of
several types of laboratory background is important for such laboratories but is too detailed and
laboratory-specific to be covered here.
10.0
QUALITY ASSURANCE OBJECTIVES AND
PROCEDURES FOR ASSESSING PRECISION AND BIAS
The objectives for precision and bias are consistent with U.S. Environmental
Protection Agency precedents (Device Protocols [EPA 1992]), and are sufficient to
meet the needs of clients.
10.1
Monitoring Bias
The objective for relative bias for the <detector name> is a percent difference (%D)
of + or - 10% . This relative bias is calculated as the difference between the measured
and the reference value divided by the reference value.
Note: Different values may be set at the QA Officer's discretion.
% D=
Measured Value - Reference Value
Reference Value
x 100
Note that the definition of percent difference is similar to the definition of Individual
Relative Error (IRE), as defined in the RMP Program Handbook (RMP Handbook [EPA
1991]), except that the numerator of the IRE is the absolute value of the difference
while %D can have positive or negative values.
To assess the results of <spiked or cross checked measurements> over time, the
results are plotted on a means control chart (see Exhibit <1 or 2>).
10.1.1 Means Control Chart to Evaluate Relative Bias From the Results of
<Spikes (for passive) or Crosschecks (for active)>
The results of <spikes or crosschecks> are plotted on a means control chart (see
Exhibits <1 and/or 2> and the associated examples in Exhibits <1A and/or 2A>). The
mean line is set at zero, and the warning and control limits are determined by
calculating the sample standard deviation (sSTD) of the resultant %D values from at
least 20 in-control <spikes or crosschecks>. (refer to Exhibit 4 for an explanation of
sSTD)
The QA Officer plots the results from the <spikes or crosschecks> on the appropriate
control chart as results are available, and checks the results as soon as they are
plotted.
10.1.2 Corrective Action Based on the Determination of High Bias
The following guidelines, taken from Taylor (Taylor 1987) are used to determine
whether the measurement system exhibits a bias high enough to warrant corrective
action.
Section No.10
Rev No. 1
Date: 6/10/94
Page 2 of 2
As the data is plotted, indicators that the measurement system may be "out-ofcontrol" include:
o
Two successive points outside the warning limits (2 X sSTD)
o
Four successive points outside the one-sigma limits (1 X sSTD)
o
A systematic trend high or low
A systematic trend includes a series of points in the same direction or successive
points all on the same side of the mean, even if all are within the control limits. If the
data exhibit any of these indicators, the measurement system should be checked and
additional QC measurements made as per the QA officer's recommendations.
10.2
Monitoring Precision
The objective for precision of the <detector name> method is an average relative
percent difference (RPD) between duplicates of 14 percent or less as calculated from
duplicates with an average exposure of 4 pCi/L or greater. Relative percent difference
is defined as the absolute difference between duplicates divided by their mean times
100, as shown below.
RPD =
Larger Result - Smaller Result
X 100
Average of Both Results
The precision objective for RPD values can be set at the discretion of the QA Officer
using the methods described in Exhibit 3.
10.2.1 The Analysis of Duplicate Measurements
To assess the range of differences between duplicates over time, the results of
duplicates are plotted on a control chart (see Exhibit 3). The control lines for the chart
in exhibit 3 are taken directly from EPA guidance (Homes Protocols [EPA 1993],
Appendix B, page B6) for measurement systems with an "in control" precision of about
14% RPD. The determination of whether the measurement system is "in control" is
made following the guidelines described in Section 10.1.2, as taken from Taylor (Taylor
1987). The results from duplicates are plotted on the duplicate control chart as they are
available, and <name and/or title> checks the results as soon as they are plotted.
11.0
QUALITY ASSURANCE AUDITS AND REPORTS TO MANAGEMENT
The QA Officer conducts an audit of QA operations at least once every <six
months>. Specific focus of the audit is on:
a) recordkeeping, including results of routine instrument checks
b) an adequate number and type of QC measurements
c) maintenance and revisions of SOP
d) adequate training and retraining of staff
The QA Officer submits a written audit report to <management or company name>
within 30 days following the audit. The audit report includes an assessment of bias and
precision, and includes recommendations as appropriate.
Note: Other information on how management receives periodic status reports on QA/QC (via
memos, or orally during staff meetings) should be described here.
12.0
CORRECTIVE ACTION
Failure of quality control measurements to be within the defined limits of this QA plan
results in immediate action to identify, correct, and document the problem. The QA
officer is responsible for ensuring timely solutions to identified problems.
13.0
QUALITY ASSURANCE TRAINING
The QA Officer has responsibility for reviewing the training plans for new staff and
the plans for retraining when procedures change. Adequate training is given high
priority, since the implementation of this QA plan is dependent upon the staff's
understanding of its requirements.
13.1
Personnel Training
All <company name> personnel are responsible for knowing everything in this QA
Plan which falls within their particular area of responsibility as defined under Section 3.1
of this plan and/or their particular company Job Description. This QA Plan is the
principle source document for the QA procedures and protocols which must be known
and practiced by responsible company personnel.
The QA Officer provides each employee with a copy of this QA Plan in which the
specific QA activities and responsibilities for that particular employee are clearly marked
and indexed. At the end of the first month of employment and at least annually
thereafter, the QA Officer checks each involved employee's knowledge and
understanding of their QA duties and responsibilities as defined in this Plan. If, in the
judgement of the QA Officer, an employee does not adequately understand his/her
responsibilities, follow-up instructions and checks are carried out until adequate
understanding is demonstrated. The QA Officer notifies the employee's supervisor of
each check result and these results are given prominent consideration in compensation
and job advancement reviews.
14.0
REFERENCES
EPA 1980
U.S. Environmental Protection Agency, 1980, "Interim Guidelines
and Specifications for Preparing Quality Assurance Project Plans,"
QAMS-005/80, Office of Monitoring Systems and Quality
Assurance, Office of Radiation Programs, Washington, D.C.
20460.
EPA 1991
U.S.
Environmental
Protection
Agency,
1991,
"Radon
Measurement Proficiency Program Handbook," EPA 520/1-91-006,
Office of Radiation and Indoor Air, Washington, DC 20460.
EPA 1992
U.S. Environmental Protection Agency, 1992, "Indoor Radon and
Radon Decay Product Measurement Device Protocols," EPA 402R-92-004, Office of Radiation and Indoor Air, Washington, DC
20460.
EPA 1992a
U.S. Environmental Protection Agency, 1992, "EPA Requirements
for Quality Assurance Project Plans," EPA QA/R-5, Quality
Assurance Management Staff, Washington, DC 20460.
EPA 1993
U.S. Environmental Protection Agency, 1993, "Protocols for Radon
and Radon Decay Product Measurements in Homes," EPA 402-R92-003, Office of Radiation and Indoor Air, Washington, DC
20460.
EPA 1993a
U.S. Environmental Protection Agency, 1993, "Home Buyer's and
Seller's Guide to Radon," EPA 402-R-93-003, Office of Radiation
and Indoor Air, Washington, DC 20460.
EPA 1993b
U.S.
Environmental
Protection
Agency,
1993,
"Radon
Measurement in Schools -- Revised Edition," EPA 402-R-92-014,
Office of Radiation and Indoor Air, Washington, DC 20460.
EPA 1993 draft
U.S. Environmental Protection Agency, June 1993 draft, "Radon
Measurement Proficiency Program: Guidance on Quality
Assurance," Office of Radiation and Indoor Air, Washington, DC
20460.
NRC 1986
U.S. Nuclear Regulatory Commission, 1986, "Accuracy and
Detection Limits for Bio Assay Measurements in Radiation
Protection", NUREG-1156, Office of Nuclear Regulatory Research,
Washington, DC
Taylor 1987
Taylor, J.K. Quality Assurance of Chemical Measurements, Lewis
Publishers; 1987.
Exhibit 1
Control Chart of Bias
of Spiked <passive detector Name> Measurements
% D=
Measured value - Reference Value
Reference Value
x 100
Measured Value is the spiked detector
Reference Value is the chamber or true value
%D
30%
20%
0%
-20%
-30%
¦
¦
¦
control limit
¦-------------------------------------------------------¦
¦
warning level
¦-------------------------------------------------------¦
¦
¦
¦
¦
¦-------------------------------------------------------¦
¦
¦
¦
¦
warning level
¦-------------------------------------------------------¦
¦
control limit
¦-------------------------------------------------------¦
¦
+-------------------------------------------------------Run number or spike date
Note: Control limits are 0 + - (3 X sSTD), and the warning levels are 0 + - (2 X sSTD). The
value of sSTD may first be assumed to be 10%, and then after gathering at least 20 spiked results
(if possible, within the same range of radon concentrations) the sSTD of the %D values can be
calculated. If it is significantly different from 10%, the above limits can be changed by the QA
Officer. See Exhibit 4 for description of how to calculate sSTD.
Note: The value for sSTD may be different at different radon levels. If possible, assess %D at
different radon concentrations. If appropriate, keep control charts for ranges of radon levels
(e.g., 4-20 pCi/L, another chart for 20-100 pCi/L, etc.). The need for separate charts is
determined by the QA Officer.
Section No.15
Rev No. 1
Date: 6/10/94
Page 2 of 6
Exhibit 1A Example
Example Control Chart of Bias
of Spiked <passive detector Name> Measurements
% D=
Measured Value - Reference Value
Reference Value
x 100
Measured Value is the spiked detector
Reference Value is the chamber or true value
%D
30%
20%
0%
-20%
-30%
¦
¦
¦
control limit
¦-------------------------------------------------------¦
¦
warning level
¦-------------------------------------------*-----------¦
*
¦
¦
*
¦
¦
¦-------------------------------------------------------¦
¦
¦
*
*
¦
¦
*
warning level
¦-------------------------------------------------------¦
¦
control limit
¦-------------------------------------------------------¦
¦
+-------------------------------------------------------12/93
12/93 12/93
4/94 4/94 4/94 ...
Data:
Measured Value:
Date:
Reference Value:
%D:
4.4 pCi/L
5.9
4.1
8.9
11.0
5.0 pCi/L
5.0
5.0
10.1
10.1
-12%
+18%
-18%
-12%
+ 9%
Spike
12/93
12/93
12/93
4/94
4/94
Section No.15
Rev No. 1
Date: 6/10/94
Page 3 of 6
12.2
10.1
Note: The sSTD of these six %D results is equal to about 17%.
+21%
4/94
Section No.15
Rev No. 1
Date: 6/10/94
Page 4 of 6
Exhibit 2
Control Chart to determine <active detector Name and serial #>
bias from crosschecked measurements
% D=
Measured Value - Reference Value
Reference Value
x 100
Measured Value is the cross-checked detector measurements
Reference Value is the recently calibrated detector measurements
%D
30%
20%
0%
-20%
-30%
¦
¦
¦
control limit
¦-------------------------------------------------------¦
¦
warning level
¦-------------------------------------------------------¦
¦
¦
¦
¦
¦-------------------------------------------------------¦
¦
¦
¦
¦
warning level
¦-------------------------------------------------------¦
¦
control limit
¦-------------------------------------------------------¦
¦
+-------------------------------------------------------Run number or cross check date
Note: Control limits are 0 + - (3 X sSTD), and the warning levels are 0 + - (2 X sSTD). The
value of sSTD may first be assumed to be 10%, and then after gathering at least 20 in-control
crosschecked results (if possible, within the same range of radon concentrations) the sSTD of the
%D values can be calculated. If it is significantly different from 10%, the above limits can be
changed. See Exhibit 4 to describe how to calculate the sSTD.
Note: The value for sSTD may be different at different radon levels. If possible, assess %D
values at different radon concentrations. If appropriate, keep control charts for ranges of radon
Section No.15
Rev No. 1
Date: 6/10/94
Page 5 of 6
levels (e.g., one chart for 4-20 pCi/L, another chart for 20-100 pCi/L, etc.). The need for
separate charts is determined by the QA Officer.
Section No.15
Rev No. 1
Date: 6/10/94
Page 6 of 6
Exhibit 2A Example
Example Control Chart for a single active monitor
to determine bias from crosschecked measurements
% D=
Measured Value - Reference Value
Reference Value
x 100
Measured Value is the cross-checked detector measurements
Reference Value is the recently calibrated detector measurements
%D
30%
20%
0%
-20%
-30%
--
¦
¦
¦
control limit
¦--------------------------------------------------------¦
¦
warning level
¦----------------------------------------*------------¦
*
¦
¦
*
¦
¦
------------------------------------------------------¦
¦
¦
*
*
¦
¦
*
warning level
¦--------------------------------------------------------¦
¦
¦
control limit
¦------------------------------------------------------¦
¦
+--------------------------------------------------------8/93 10/93 12/93
2/94 4/94 6/94 ...
Data:
Measured Value:
Date:
6.3 pCi/L
5.9
6.2
Reference Value:
6.0 pCi/L
5.0
7.5
%D:
-12%
18%
-18%
Cross
Check
8/93
10/93
12/93
Section No.15
Rev No. 1
Date: 6/10/94
Page 7 of 6
8.9
8.8
19.6
10.1
8.1
16.2
-12%
9%
21%
2/94
4/94
6/94
Note: The sSTD of these six %D results from an individual active monitor is equal to about 17%.
Section No.15
Rev No. 1
Date: 6/10/94
Page 8 of 6
Exhibit 3
Duplicate Control Chart
for determination of <detector Name> precision
This chart only uses duplicates from similar detectors
where the average of the two is > 4 pCi/L
RPD =
RPD
36%
28%
14%
Larger Result - Smaller Result
X 100
Average of Both Results
¦
¦
¦
¦
¦ control limit
Note: expect to see results above
¦----------------------------------------------------¦
this level only 1% of the time
¦
¦ warning level
¦----------------------------------------------------¦
¦
¦
¦
¦ in-control level
Note: results are routinely
¦----------------------------------------------------¦
around this level of precision
¦
¦
¦
¦
¦
+------------------------------------------------------
Note: Control limits are 0 + - (2.6 X sSTD), and the warning levels are 0 + - (2 X sSTD). The
value of sSTD may first be assumed to be 14%, and then after gathering at least 20 in-control
duplicate results (if possible, within the same range of radon concentrations) the sSTD of the
RPD values can be calculated. If it is significantly different from 14%, the above limits can be
changed. See Exhibit 4 for description of how to calculate the sSTD.
Note: This chart's control limit is approximately 2.6 times the sSTD (EPA 1993), and represents
a level which is expected to be exceeded by chance about 1% of the time. (If a 3 X sSTD level or
42% RPD were used it would be expected to be exceeded by chance less than 0.5% of the time).
The sSTD value of 14% can be used until a sufficient number (at least 20 pairs) of duplicates
that are in-control and measure greater than 4 pCi/L have been made. If the sSTD of the RPD of
Section No.15
Rev No. 1
Date: 6/10/94
Page 9 of 6
these pairs is significantly different than 14%, the draft EPA guidance on QA for RMP
participants (EPA 1993 draft) or the EPA Homes Protocols (EPA 1993) guidance on how to set
the proper control limits is consulted to determine how to set different limits.
Section No.15
Rev No. 1
Date: 6/10/94
Page 10 of 6
Exhibit 4
Calculation of Sample Standard Deviation
The sample standard deviation (sSTD) can be obtained using a spreadsheet computer program or
a scientific calculator. For sSTD calculations in this QA plan the following formula can be used.
n
( x - x
i
sSTD =
2
avg
)
i=1
n -1
= square root of the value
n = number of values
n

= the sum of whatever follows
i=1
x i = each value
x avg = avg of the values
( x i - x avg )2 = square of each value difference from the avg
Note: In this QA plan only sSTD (sample or population standard deviation) is used. The
difference between standard deviation (STD or sigma) and sSTD is that sSTD is obtained by
multiplying STD by ( n/n-1 ). Both sSTD and STD are usually obtained by using a scientific
hand calculator or computer spreadsheet program. To obtain the correct control chart levels, the
sSTD of at least 20 %D or RPD values, which were judged to be in-control, are computed. The
control chart warning level is set at 2 times the sSTD. The out of control level is set at 3 times
the sSTD for cross checks and spikes and 2.6 times the sSTD for duplicates. Duplicates have a
more stringent out of control level because they are only evaluating precision and not system
bias.
APPENDIX A
NON-INTERFERENCE RADON SURVEY AGREEMENT
REQUIRED TEST CONDITIONS
Radon and radon decay product concentrations in a dwelling fluctuate from hour to hour, day to day and
season to season. The following test recommendations were developed by the EPA to provide
standardized conditions under which a short-term radon survey is to be performed in order to reduce the
variation in radon levels in a dwelling. These conditions tend to maximize the radon measurement in
order to determine if a dwelling has the "potential" to have an elevated radon level. If the result is
elevated, the EPA recommends further testing to determine better the yearly average concentration.
If the test conditions below are not adhered to, the test results may be deemed invalid.
The following conditions must be read, understood and followed:
All exterior windows must be kept closed. All exterior and the basement to first floor doors must be kept
closed except for normal, momentary entering and exiting.
The radon detector cannot be moved, covered or altered in any way. Heating, air conditioning, dryers,
range hoods, bathroom fans and attic ventilators can be operated normally. If any heating, air conditioning
or ventilating equipment has a built in outdoor air supply that is manually controlled, it is turned off or the
inlet closed. Fireplaces or wood stoves are not operated, unless they are a primary heat source. Whole
house fans are not operated. Window fans are removed or sealed shut.
These test conditions are maintained for 12 hours prior to the start of the radon detector being exposed,
unless the test is longer than four days in duration.
If there are any questions, or test conditions are not met, please contact the test company at (Co. Ph #)
I/We the responsible individual or building custodian understand and will inform all occupants of this
dwelling of the above conditions of the test. I/we agree to maintain these conditions during the test period.
Property Address:
Detector Type & Locations
Test
Technician:
1st:
Responsible
Individual:
2nd:
Real Estate Agent:
3rd:
Date Signed:
Installed
Date/Time:
Comments:
Retrieval
Date/Time:
APPENDIX B
RADON SURVEY IN PROGRESS
DO NOT REMOVE THIS NOTIFICATION
The following conditions must be maintained:
 Do not open any windows. Do not open any external or basement to first floor doors
except for normal momentary entering and exiting.
 Do not touch, cover, move or alter the performance of any radon detectors or
non-interference controls.
 Do not operate any whole house fan(s). Do not use any fireplace(s) or wood
stove(s), unless they are the primary heat source.
 Operate heating and air conditioning normally. Turn off and keep off any equipment
that supplies fresh air to the dwelling unless it is make up air to a combustion
appliance.
NOTE:
The dryer, range hood, bathroom fan or attic ventilating fan can be operated. This
equipment is operated normally because any exhaust fan or any combustion appliance
may increase the negative pressure in the dwelling, which can raise or lower the radon
concentration. Windows must be kept closed because they can create negative
pressure in the lower portions of the dwelling due to the warm air escaping or the
direction of the wind, which can raise or lower the radon levels. Please contact (Testing
Company Name & Phone Number) if there are any questions or concerns.
Test Period From:
Responsible Individual:
Date:
To:
APPENDIX C
EXAMPLE RADON TEST REPORT
Test Company
Street Address
City, State Zip
Phone & Fax Number
Radon levels tend to vary.
We accept no liability for
any or all loss due to the
results of this or these tests
Customer Name
Street Address
City, State Zip
Date:
Test id#:
Test Type:
Cus H Ph:
Cus W Ph:
Test Location: <Street, City, State Zip>
Note: Customer signed agreement to maintain closed-house conditions
Detector Placed by: <Technician Name & RMP ID #>
Comments: None
---------------------------------------------------------------------------------------------------------------------------------------The following measurements were made with: <Detector Type>
Detr
Id #
------5475 Bas
5085 Bas
Test Start
Start
Rm
Date
----------------02/21/94
09:40
02/21/94
09:40
Stop
Stop
Time
Date
-------- --------02/23/94
10:30
02/23/94
10:30
| Radon |
| pCi/L
--------| 5.6 |
| 5.2 |
------Bas Average =
5.4
Time
--------
+/|
pCi/L
-------0.3
0.3
pCi/L
6027 1Fl
02/21/94
09:45 02/23/94
10:25
| 1.8 |
0.2
------------------------------------------------------------------------------------------------------------------------------------------THE AVERAGE RESULTS WERE ABOVE EPA GUIDELINES
The EPA recommends that any lived-in areas of a home that measure greater than 4 pCi/L (or any areas that are suitable
for occupancy without renovation, if the home is involved in a Real Estate Transaction) be mitigated to below 4 pCi/L. If
the measurement is below 4 pCi/L then additional mitigation to reduce the levels is not necessary. It is the client's
obligation to inform the dwelling occupants of the results of the measurement.
Note: Homeowner is responsible for additional follow-up testing. Retesting should take place with each change of
ownership, structural alterations to the dwelling that changes the ventilation pattern, major cracks occurring in the
foundation or nearby blasting or earthquakes, and after every two years.
There is uncertainty with any measurement result due to: statistical variations, daily and seasonal radon variations due to
changes in the weather and operation of the dwelling as well as possible interference with the necessary test conditions
that may or may not influence the results.