Setting Action Levels
and
Controlling exposure with Air
Monitoring
A review...
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Objectives
Understand the factors that go into establishing
an action level
Understand the variables affecting action levels
when working with multiple chemical
contaminants
Understand how to monitor VOCs in the air and
metals in airborne dust particles
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Why set Action Levels?
Protect against the inhalation of toxic materials
Protect against the absorption of toxic materials
Protect against other affects of toxic materials
Protect against explosion and oxygen
deficiency/enrichment
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Challenges
What are the challenges that are
important to consider in setting
action levels?
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Challenges
Chemicals of concern
PEL/REL/TLV, IDLH
Exposure pathways
Inhalation
Absorption
Ingestion
Injection
Concentrations of chemical
Physical state of chemical
gas, solid mist, vapor, fume, particles
density, vapor pressure, etc…
Environment of the work zone
Temperature
Access
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Other considerations
Nature of the work
PPE levels of protection available
(A/B/C/D)
Training
Physical demands
Work activity
Respirator compatibility
PPE compatibility
Physical condition of the workers
Air monitoring instrumentation
limitations and capabilities
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Resources available to
help you...
NIOSH pocket guide
PEL/REL
Ionization potential (Ip)
Physical characteristics
Recommended respirators
ACGIH TLV/BEI book
SMS 17 Hazardous Waste Operations
SMS 43 Personal Monitoring
SMS 050 Specific Chemical Hazards
Your Regional H&S Manager
One of the 50+ CSP/CIH/CHPs in URS
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The focus today….
Action levels for inhalation risks particularly
between Level D and C PPE
Particular emphasis on
VOCs
Particulates
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Volatile Organic
Compound
A VOC is...
an organic compound (carbon)
typically an inhalation and absorption hazard
typically present in low levels on a site
Chemical
TLV______ IDLH
REL*
PEL
Ionization
Potential
Xylene
100PPM
100 PPM
100 PPM
900 PPM
8.56 eV
Toluene
50 PPM
100 PPM
200 PPM
500 PPM
8.82 eV
Benzene
0.5 PPM
0.1PPM
1.0 PPM
500 PPM
(Ca)
9.24 Ev
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* REL from NIOSH
Typical VOC site...
Action levels… depend first on
an instrument:
PID with a 10.6 eV bulb
 Calibrated to hexane?
Isobutylene?
 What is the relative response
(response factor)?
Air monitoring is completed in
the Operator’s Breathing Zone
Greater than 3 minutes
(sometimes 5 minutes)
15 meter units (or 25, or 50)
above background with a PID
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But what about Benzene?
How can an action level of 15 meter units be
acceptable if Benzene is a possible chemical of
concern?
Chemical TLV______ IDLH
Ionization
REL
Potential
PEL
Xylene
100PPM
100 PPM
100 PPM
900 PPM 8.56 eV
Toluene
50 PPM
100 PPM
200 PPM
500 PPM 8.82 eV
Benzene
0.5 PPM
0.1PPM
1.0 PPM
500 PPM 9.24 Ev
(Ca)
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Solution
Add another “level” to the action levels.
Have the ability to discriminate Benzene from other
VOCs. This can be done easily with a colorimetric
tube, a Benzene chip detector, or a Benzene PID
pre-filter.
If > 2 PPM (meter units) in the OBZ for more than 5
minutes, test for Benzene. If no Benzene, increase
action level to 15/25/50 meter units using the PID.
Or upgrade to Level C…
(Why is the IDLH level
important when using
Level C PPE?)
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What if?
You have a PCE site with Vinyl Chloride
contamination...
Chemical
TLV______ IDLH
REL
PEL
Perclorethylene
25 PPM
Ca
100 PPM
1 PPM
Ca
1 PPM
(aka tetrachlorethylene)
Vinyl Chloride
Ionization
Potential
300 PPM 9.32eV
None
9.99 eV
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Solution?
Eliminate the potential of VC in the breathing
area - use a colorimetric tube or CHIP for VC in
combination with a PID.
If > 3 meter units in the OBZ for more than 3
minutes, test for Vinyl Chloride. If no VC is
present, increase action level to 10 meter units.
Question… Can you upgrade to Level C if VC is
present above 1 PPM?
What was that IDLH?
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Action Level Matrix for
BTEX scenario
PID Reading
Action
In Operator Breathing
Zone for more than 3
minutes
(PID with 10.6 eV bulb)
(Draeger Benzene Chip
Detector)
0-2 PPM
Conduct Air
monitoring every 15
Minutes
Level D PPE
>2 PPM
Test for Benzene
using Benzene
Monitor
>2 & <50 PPM
Conduct Monitoring
every 15 minutes
with the PID and
every 30-60 minutes
with a Benzene
Monitor
If Benzene is present
> 1 PPM, Notify
RHSM. Upgrade to
Level C PPE with OV
cartridge. Stop work if
Benzene exceeds 2.5
PPM.
If greater than 2 PPM
Benzene, or greater
than 50 PPM on the
PID indicated,
upgrade to Level C
PPW with OV
cartridge. Notify the
RHSM.
(with NO Benzene)
Note
(modified) required.
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Contaminated Soils
The challenge is often Lead (Pb) or Arsenic (As)
Other metals
May also include PCBs and PAHs
Typically present an inhalation hazard - expressed an mg/m3
TLV______
Chemical REL
PEL
IDLH
Ionization
Potential
NA
Lead
(Pb)
0.1 mg/m3
0.05 mg/m3
0.05 mg/m3
100 mg/m3
Arsenic
(As)
0.01 mg/m3
None
0.5 mg/m3
5 mg/m
NA
Airborne
particulates
3 mg/m3 (respirable)
10 mg/m3 (inhalable)
3 mg/m3 (respirable)
10 mg/m3 (inhalable)
5 mg/m3 (respirable)
15 mg/m3 (inhalable)
None
NA
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Scenario
Contaminated soils site. Pb
in the soil is present at 1000
mg/kg
What amount of airborne Pb
soil particles should we set
as permissible to breath?
How are we measuring the
particles in air?
 (mg/m 3)
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The Pb example in formula...
The formula for equivalent dust concentration:
Exposure Limit = (106 mg/kg) (TLV or PEL in mg/m 3)
(conc in soil in mg/kg) (safety factor)
(106 mg/kg) (TLV or PEL in mg/m3)
(conc in soil in mg/kg) (safety factor)
106 * 0.05mg/m3
1000 * 2
= 25 mg/m3
Safety factors are:
2 when site data is good; highly confident
4 when site data is okay; some confidence
10 when no data exists; no confidence
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And finally...
Remember what the exposure to Dust was limited
to?
10 mg/m3 inhalable
3 mg/m3 respirable
So the maximum exposure level on the site for soils
with 100 mg/kg of Pb is 10 mg/m3 even though we
could go to 25 mg/m3 for Pb.
Above 10 mg/m3 in the air (TLV-TWA) workers
should be in level C PPE with a particulate filter (P100).
Note: typically dust is visible in the air at 5 mg/m3
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Action Levels for Intrusive Activities
Monitoring
Equipment
Sampling Result/Observation
Action
PID (10.6 eV lamp)
>1 ppm
Continue to monitor with PID; monitor
with benzene chips.
Benzene detector chip
(with CMS device)
<0.5 ppm
Continue to monitor with PID.
0.5 ppm, <25 ppm
Upgrade to Level C. Continue to
monitor with PID.
25 ppm
Stop work; evacuate area and contact
HSM.
>1 ppm, 25 ppm; IF no
benzene detected
Continue to monitor with PID.
>25 ppm, 250 ppm; IF no
benzene detected
Upgrade to Level C. Continue to
monitor with PID.
>250 ppm
Stop work; evacuate area; contact HSM.
Hydrogen sulfide
monitor
2.5 ppm
Stop work; evacuate area; contact HSM.
MiniRam Dust
Monitor
>15 mg/m3
Use dust control measures until dust is
controlled. If dust cannot be controlled
upgrade to Level C.
Observation
Workers enter sheds or utility
buildings where rodents may
have nested; and workers may
disturb nesting materials or
rodent droppings.
Upgrade to Level C.
Observation
Workers exhibit symptoms of
chemical exposure
Stop work. Evacuate area and contact
the HSM.
PID (10.6 eV lamp)
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