ACGIH BEIs / TLVs Flashcards
TLV definition
Airborne concentrations of chemical substances that represent conditions under which it is believed that nearly all workers may be repeatedly exposed, day after day, over a working lifetime, without adverse health effects
What does a TWA measure?
Concentration for a conventional 8-hour workday and 40-hour workweek, to which it is believed that nearly all workers may be repeatedly exposed, day after day, for a working lifetime without adverse effects
What does a STEL measure?
A 15-minute TWA exposure that should not be exceeded at any time during a workday, even if the 8-hour TWA is within the TLV-TWA
What does a STEL protect workers from?
Workers can be exposed to the STEL without suffering from 1) irritation 2) chronic or irreversible tissue damage 3) dose-rate dependent toxic effects, or 4) narcosis
How often can you be exposed to the STEL?
- Exposure should always be less than 15 minutes
- Should occur no more than 4x per day
- There should be at least 60 minute between successive exposure in this range
TWA SL
The concentration on workplace equipment and facility surfaces that is not likely to result in adverse effects following direct or indirect contact
Ceiling value
The concentration that should not be exceeded during any part of the working exposure
Peak exposure - when are they applicable
When a STEL does not exist for a substance (even if there’s a TLV-TWA)
Peak exposure rules
May exceed 3x the TLV-TWA for no more than 15 minutes at a time, for no more than 4 occasions spaced out one hour apart during a work day
May never exceed 5x the TLV-TWA when measured as a 15 minute TWA
When are ceiling values more appropriate to use rather than TLV-TWAs?
When substances are fast acting and whose TLV is more appropriately based on the concentration associated with this particular response
What are BEIs?
They are guidance levels for evaluating biological monitoring results. BEIs generally represent the levels of determinants that are most likely to be observed in specimens collected from healthy workers who have been exposed to chemicals to the same extent as workers with inhalation exposure
Biological monitoring can assist with:
- determine absorption via the skin or gastrointestinal route
- assess body burden
- reconstruct past exposure
- detect nonoccupational exposures among workers
- test the efficacy of PPE and engineering controls
- Monitor work practices
What are the specimens used in BEIs?
Urine, blood, or exhaled air
Prior to shift sampling time (BEI)
16 hours after exposure ceases, but before any exposure on sampling day
Prior to last shift sampling time (BEI)
Prior to last shift of a workweek
Increase during shift sampling time (BEI)
Requires pre and post shift sample collection
End of shift sampling time (BEI)
As soon as possible after exposure ceases
Carbon monoxide
Organophosphates
End of workweek sampling time (BEI)
After 4 or 5 consecutive working days with exposure
Discretionary/non critical sampling time (BEI)
At any time
Lead
Cadmium
For urine sample, creatinine levels must be within what range to be valid?
0.3 g/L < X < 3 g/L
Cadmium determinant / sampling time (BEI)
Cadmium in urine | not critical (sampling time)
Cadmium in blood | not critical (sampling time)
Carbon monoxide determinant / sampling time (BEI)
Carboxyhemoglobin in blood | end of shift (sampling time)
Carboxyhemoglobin in end-exhaled air | end of shift (sampling time)
Mercury determinant / sampling time (BEI)
Mercury in urine | prior to shift (sampling time)
Parathion determinant / sampling time (BEI)
Total p-Nitrophenol in urine| end of shift
Acetylcholinesterase in red blood cells | end of shift
Western red cedar TWA
0.5 mg/m3
All other species of wood TWA
1 mg/m3
Oak and beech carcinogenicy
A1
Birch, mahogany, teak, walnut carcinogenicity
A2
Western red cedar carcinogenicity
A4
