BGI

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Introduction to BGI
Instruments
Tom Merrifield
BGI Instruments
58 Guinan St.,Waltham, MA 02451
T:+781 891-9380 info@bgiusa.com
http://www.bgiusa.com
Introduction
EPA has begun evaluation of PM2.5
Continuous Monitoring Candidate
Instruments for AQI and new regulatory
network to compliment manual FRM
FEM Class III Equivalency procedures in
1997 CFR perceived as technically nearimpossible, cost-prohibitive
Draft changes to NAAQS for 2003 may allow
use of continuous monitors for PM2.5
reporting to AIRS and AQI
2
U.S. EPA Ambient
PM Timeline
3
EPA, State, Tribal and
Local AQ Priorities
–
New PMc Coarse Particulate Matter Network
– (PMc) PM10 - PM2.5 = PMc
– Develop continuous PM methods for AQI and AIRS
– Reduce labor costs
– May improve data quality & usefulness
– May increase public awareness
– Reference (FRMs) & Equivalent (FEMs) program
remains a critical component of NAAQS
4
Methods for Ambient
PM Sampling
– Reference method
–Gravimetric Filter collection & weighing (manual)
– Candidate equivalent method(s)
–Beta attenuation
– Harmonic Dampening(TEOM™ & Vibrating
Crystal)
– Light scatter & extinction (photometer & COH)
5
EPA Designation Status
Fine particulate monitor, model FPM
PM10
Field trials completed. application and
approval for PM10 June
PM2.5
EPA OAQPS with CASAC proposing
regional equivalency and data quality
management for PM2.5
6
Model FPM Continuous
PM Monitor – Pros
High sensitivity, zero stability
Short-term measurements
Our goals
Report hourly PM2.5 automatically for >7
days without site visit
Little PM2.5 bias in relationship to FRM
Similar operation and filter temperature
like FRM
Filter humidity controlled to < 45% with 8°C
7
maximum overheat
Model FPM Continuous
PM Monitor – Cons
Interference of ambient humidity/artifacts
Exempt quantity of beta energy
No EPA approval for PM2.5 until June ‘03
No mass calibration or speciation
Time interval of one hour or greater
Cost of automation compared to manual FRM
Electronic data collection complexity
Validation of sample & data
8
Introduction to the
BGI Model FPM
BGI Model FPM (fine particulate matter monitor)
PM2.5 Inlet with BGI Very Sharp Cut Cyclone
(VSCC)
PM2.5 concentration measured & reported on
hourly and 24 hour average
Continuous operation of six weeks
Filter change hourly to prevent loss of semivolatile particulate
New generation of high sensitivity beta attenuation
monitor (FPM BAM)
9
BGI FPM
Sensitivity
±1.5g/m3
Precision
r2 > 0.90 to FRM
Site factor (optional)
Repeatability
± 2%
Active sample cycle
56 minutes each hour
4-minute diagnostic test
each hour
10
BGI Very Sharp Cut Cyclone Inlet
90-Day Operation between Maintenance
11
EPA Field Comparison of Candidate
PM2.5 Continuous Monitors to FRM
12
FPM Outdoor Shelter
Inlet
FRM design with
VSCC
16.67 alpm
Temperaturecontrolled shelter
Backup data printer &
error log
Mass Foil standards
Zero stability test
High mass calibration
13
Model FPM Outdoor and
Indoor Models
14
Calibration and Audit of FPM
Manual use of factory span and zero
calibration tools-recommended each
calendar quarter or when filter tape
changed
Audit - Seasonal or annual comparison
with FRM audit sampler.
EPA agreement not final, but >0.85 r
15
Maintenance Requirements
Six weeks change filter tape
Validate flow rate, ambient temperature
and barometric pressure sensors each six
weeks
Clean PM10 FRM Inlet and PM2.5 VSCC
each 3 months
Replace printer paper and printer
cartridge each 3 months
Rebuild vacuum pump each 18 months
16
Data Management &
Collection
FPM includes hard copy field printer
with hourly concentration and min/max
for 24 hour. Faults reported in red ink
Analog output with 0-1 or 0-5 Volts DC
which are scaled to concentration
RS-232 Digital Download using
FPM-230 software
17
FPM Applications
Air Quality Index (AQI)
New PM2.5 Continuous NAM/SLAMS
Network
Epidemiology & public health studies
Hourly reports of PM2.5 concentrations
Digital and analog data communication
Cell phone compatible
PM10, PM2.5 and PM1 inlet compatible
Stand alone environmental shelter
18
NIST Traceable Volumetric Flow
Rate, Temperature and Pressure
Calibration/Audit Device for FRM
and Continuous Ambient Monitors
Introduction
Federal, state and local agencies require flow
calibration and audits on all ambient
particulate samplers and monitors
Commercial claims of “primary flow” and
“NIST traceability” are confusing
New NIST traceable volumetric flow rate,
ambient temperature and pressure field
calibration/audit device developed, tested
20
Investigation
Primary standard vs. flow transfer
standard
Requirements for field flow calibrator
Current methods available
How DeltaCal meets requirements
21
NIST Primary & EPA Flow
Transfer Standards
–NIST primary flow calibration facility
–Colorado Engineering Experiment Station
(CEESI)
–Titanium Vessels - gravimetric analysis
standard
–Pressurized and weighed for volume. air flow
measured through a NIST flow transfer Venturi
–Flow transfer standard
– Traceable Calibrator to NIST (CEESI) Primary
22
CEESI - NIST Primary
Calibration Lab
23
Priorities of a Field Flow
Calibrator
– NIST transfer standard, accuracy to < 2%
– Calibrator must be field usable to EPA FRM specs
– Insensitive to atmospheric conditions
– Calibrator should not add artificial pressure to
sampler to interfere with electronic flow controller
– Portable & battery powered
– Direct reading of flow rate, ambient temperature,
& barometric pressure
– RS232 calibration report-digital calibration report
24
“Flow Transfer Standard”
Calibrators
– Bubble meter
– Gilibrator™ (wet) - (excellent for indoor use)
– Frictionless piston -
(Not field hardened)
– Bios/DryCal/DC-Lite™ (dry)- 3% low bias
– Orifice- quartz tube - (sensitive to wind)
– Streamline/Chinook™ (dry) – adds system
pressure, double of a Venturi
– Venturi- Delrin™ plastic - (field hardened with gust cap)
– BGI DeltaCal (dry) – flow, temperature & pressure
25
DeltaCal Calibration Kit
DeltaCal

Measurements
•
•
•
•
•
Barometric pressure
Ambient temperature
Filter temperature
Volumetric flow rate
Digital output for
recording and audit
report
26
Schematic Diagram
of DeltaCal
AMBIENT TEMP. PROBE
AIR FLOW
DIFF. PRESSURE
SENSOR
VENTURI
MICRO PROCESSOR
TO FRM
SAMPLER
BAROMETRIC
PRESSURE
SENSOR
B.P. 760 mm Hg
Tfil:
23.0°
Tamb: 23.0°
Q 16.67 LPM
Batt%
90
FILTER TEMP.
PROBE
LCD DISPLAY SCREEN
Figure 4- Schematic Diagram of deltaCal
2168
27
DeltaCal NIST Traceable
Specifications
–
–
Operable range –30 to 40C
–
2 to 20 aLPM (US FRM & Continuous PM)
–
10 to 50 aLPM (Europe)
–
+/- 1% of NIST
Temp sensor range –40 to 50C
–
–
< +/- 0.5C Difference to NIST
Pressure range 400-800mmHg
–
< +/- 2mmHg of NIST
28
DeltaCal Computer
Screen Display
Historical record
User configurable
All readings in one
display
Auto resolution
ASCII file export
Flow statistics
29
BGI - NIST Traceable Flow
Calibration Laboratory
– < Insert photo of BGI Test Bench >
30
Conclusions
BGI DeltaCal is flow transfer standard traceable
to NIST primary
Meets all requirements
Only field-hardened device with low pressure
drop, includes wind gust cap
Cost includes 4 measurements, rather than 1
Affordable annual calibration by single vendor
US E.P.A. tested – exclusive for PEP QA
program
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