Limit, short term exposure control

Specific short-term exposure limits are listed by the HSE for those chemicals which pose a risk of acute effects from brief exposures. For other chemicals a recommended guideline for controlling short-term excursions is to restrict them to 3x long-term exposure limit averaged over a 10min period. 

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... 

NPDES = National Pollutant Discharge Elimination System NTP = National Toxicology Program OSHA = Occupational Safety and Health Administration OW = Office of Water PCB = Polychlorinated Biphenyl RfD = Reference Dose STEL = Short-term Exposure Limit TLV = Threshold Limit Value TSCA = Toxic Substances Control Act TWA = Time Weighted Average WHO = World Health Organization... 

The control limits should not be exceeded and wherever possible reduced, and in any case these substances are subject to specific Regulations or Codes of Practice. The RL values are annually reviewed, but the CL values may be altered at shorter time intervals. The TLV value is used in the UK if a RL or CL value is not available. With some substances, long-term or short-term exposure limit values (LTEL or STEL) are published. Finally it should be noted that the Council of Europe is proposing to introduce a harmonised list of exposure standards for adoption by the EEC countries. 

MACT maximum achievable control technology STEL short-term exposure limit... 

Finding 3-2. Currently, permit provisions at the various sites require the use of a variety of parameters (including the short-term exposure limit, the short-term limit, the waste control limit, the permit compliance concentration, the vapor screening level, and the Army s X-based notations) for characterizing secondary waste from the chemical agent disposal processes. This inconsistency inhibits clear communication with and understanding by the broader population. 

Most data on human responses to sulfate are based on short-term exposures that are obtained from controlled settings (i.e., studies and experimental trials). The risk of adverse health effects to the general population is limited and acute, and such effects occur only at high drinking water concentrations (>500mgl , and in many cases >1000mgH ). 

American Conference of Governmental Industrial Hygienists threshold limit value (TLV) lOmgm for total zinc oxide dust (containing no asbestos and <1% crystalline silica), as a TWA for a normal 8h workday and a 40h workweek TLV — TWA of 5mgm and a TLV — STEL (short-term exposure limit) of lOmgm for zinc oxide fume (based on providing reasonable control of this nuisance dust). 

OSHA requires employers of workers who are occupationally exposed to formaldehyde to institute engineering controls and work practices to reduce and maintain employee exposure at or below permissible exposure limits (PELs). The employer must use controls and practices, if feasible, to reduce exposure to or below an 8-hour time-weighted average (TWA) of 0.75 ppm. The 15-minute, short-term exposure limit (STEL) for formaldehyde is 2 ppm (OSHA 1992). 

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