PEL-time-weighted average

ACGIH Permissible Exposure Limit (PEL)-Time-weighted Average (TWA) Hexane 50 ppm (176 mg/m3) ACGIH 1996... 

Air US OSHA Permissible exposure limit (PEL) — time weighted average (TWA) of 8 h 10 pg m-3... 

US OSHA permissible exposure limit (PEL) time-weighted average (TWA) value of 0.1 ppm (0.25 mg m ) short-term exposure limit (STEL) value of 0.3 ppm (0.8 mg m ), not to exceed 15 min. 

The Occupational Safety and Health Administration permissible exposure limit (PEL) time-weighted average (TWA) for nickel metal and other nickel compounds as nickel is 1 mg m the PEL TWA for nickel carbonyl is 0.007 mg m . The ACGIH threshold limit values (TLVs) for nickel metal, insoluble compounds, soluble compounds, nickel carbonyl, and nickel subsulflde, all expressed as nickel, are 1.5, 0.2, 0.1, 0.12, and 0.1 mgm, respectively. Except for nickel carbonyl, all of the TLVs are expressed as inhalable particulate. The US EPA reference dose for soluble nickel salts is 0.02 mg kg day, but this value is undergoing reevaluation, due to the availability of several relevant new studies. 

Occupational Safety and Health Administration (OSHA) Permissible Exposure Limits (PEL) Time Weighted Average (TWA). Similar to the ACGIH TLV TWA but issued as a regulation by OSHA to protect workers. PELs are published in Title 29 of the Code of Federal Regulations (CFR) Part 1900 Section 1000. 

The Occupational Safety and Health Administration (OSHA) Toxic and Hazardous Substances (Tables Z.l, Z.2, and Z.3) of air contaminants, found in 29 CFR 1910.1000. These tables record permissible exposure limits (PELs), time-weighted averages (TWAs), and ceiling concentrations for the materials listed. Any material found in these tables is considered to be hazardous. The tables can be viewed on OSHA s Web site ... 

For worker exposure to trichloroethylene vapor, OSHA set a maximum eight-hour time-weighted average (TWA) concentration of 100 ppm. This severely restricted certain appHcations, and many organizations converted to other chlorinated solvents. As a result, U.S. production of trichloroethylene declined about 70% from a peak in 1970 (Table 2). In 1989, OSHA lowered the permissible exposure limit (PEL) from 100 ppm eight-hour TWA to 50 ppm eight-hour TWA (33). This added further pressure for some users to consider changing to alternative solvents. 

Workplace. The Occupational Safety and Health Administration (OHSA) has estabUshed workplace permissible exposure limits (PEL) for chromium metal and three forms of chromium compounds. OSHA s PEL for chromic acid and chromates is 0.1 mg/m 3 both a ceiling, ie, no exposure above this concentration is allowed, and an 8-h time-weighted average (TWA). Chromium metal and insoluble chromium salts have an 8-h TWA PEL of 1.0 mg/m Cr, and the same standard is 0.5 mg/m Cr for soluble Cr(III) and Cr(II) compounds (144). 

The time-weighted average OSHA permissible exposure limit (PEL), as weU as the ACGIH threshold limit value (TLV), for cyclohexanone is 25... 

Permissible exposure limit (PEL) The maximum exposure level allowed by OSFiA, expressed as an 8-liour time-weighted average. These are legally enforceable in the U.S. 

Permissible Exposure Limit (PEL) expressed as a time-weighted average, is the concentration of a substance to which most workers can be exposed w ithout adverse effects, averaged o cr a normal 8-li workday or a 40-li workweek. 

EL = emissions level ERA = Environmental Protection Agency HSDB = Hazardous Substances Data Bank lARC = International Agency for Research on Cancer IRIS = Integrated Risk Information System NIOSH = National Institute of Occupational Safety and Health OEL = occupational exposure limit OSHA = Occupational Safety and Health Administration PEL = permissible exposure limit RAC = reference air concentration REL = recommended exposure limit RCRA = Resource Conservation and Recovery Act RfD = reference dose TLV = threshold limit value TWA = time-weighted average WHO = World Health Organization... 

OSHA = Occupational Safety and Health Administration PAGs = protective action goals PEL = permissible exposure limit S = soluble REL = recommended exposure limit TWA = time-weighted average... 

OSHA PEL-8-hour time weighted average None OSHA 1998c (29 CFR 1910.1000 Table Z-2)... 

PEL Pg pmol PHS PMR ppb ppm ppt REL RfD RTECS sec SCE SIC SIR SMR STEL STORET TLV TSCA TRI TRS TWA u.s. UF yr WHO wk permissible exposure limit picogram picomole Public Health Service proportionate mortality ratio parts per billion parts per million parts per trillion recommended exposure limit Reference Dose Registry of Toxic Effects of Chemical Substances second sister chromatid exchange Standard Industrial Classification Standardized incidence ratio standard mortality ratio short term exposure limit STORAGE and RETRIEVAL threshold limit value Toxic Substances Control Act Toxics Release Inventory total reduced sulfur time-weighted average United States uncertainty factor year World Health Organization week... 

OSHA requires employers of workers who are occupationally exposed to a toxic or hazardous substance to institute engineering controls and work practices that maintain or reduce their exposure to a level that is at or below the permissible exposure limit (PEL) established for the substance. For occupational exposures to lead, the employer must use engineering controls and work practices to achieve an occupational exposure of 50 pg/nr3 (0.006 ppm) or lower, based on an 8-hour time-weighted average (TWA) (OSHA 1995). When employee exposures to lead can not be maintained at or below 50 pg/rn3... 

OSHA PEL Federal Permissible Exposure Limits based on a time-weighted average exposure over an 8-h period and 40-h work week. A [Skin] notation indicates that percutaneous absorption of the material is a potential hazard and may contribute to the overall exposure. 

The PELs are promulgated by OSHA and have force of law. These levels are similar to the ACGIH criteria for TLV-TWAs because they are also based on 8-hr time-weighted average exposures. OSHA-cited acceptable ceiling concentrations, excursion limits, or action levels may be appropriate for use as benchmarks. 

TIN-TWA Threshold limit value, time-weighted average for 8-h exposures, with ceiling concentrations shown as C, and with skin absorption hazard as S. The OSHA permissible exposure limit (PEL) is the lower of the TWA or the ceiling limit. 

Permissible Exposure Limit (PEL) The maximum time-weighted average concentration mandated by OSHA to which workers may be repeatedly exposed for eight hours a day, forty hours per week without adverse health effects. 

Threshold Limit Value Airborne concentrations of substances devised by the ACGIH that represent conditions under which it is believed that nearly all workers maybe exposed day after day with no adverse effect. TLV s are advisory exposure guidelines, not legal standards, based on evidence from industrial experience, animal studies, or human studies when they exist. There are three different types of TLV s Time Weighted Average (TLV-TWA) Short Term Exposure Limit (TLV-STEL) and Ceiling (TLV-C). (See also PEL)... 

---