Occupational exposure limits phosgene

The occupational exposure limits assigned to phosgene may vary not only from country to country, but also from authority to authority. They are not only subject to change with the passage of time, but may also vary between different work environments. Some industrial companies follow their own standards, where these are more stringent than those set by the health and safety authorities [40]. Clearly, there are no sharp boundaries at which concentrations of phosgene are "safe" and at which some are "dangerous" to the human... 

Occupational exposure to phosgene" has been defined by NIOSH [1484] as exposure above half of the recommended time-weighted average (TWA) environmental limit whilst "overexposure" is defined as known or suspected exposure above either the TWA or ceiling concentration, or any exposure which results in the development of pulmonary symptoms. 

Phosgene cannot be detected by smell (see Section 3.1.3) at the generally accepted occupational exposure limit of 0.1 p.p.m. [43,1703]. Although the sense of smell undoubtedly acts as a natural safety detection warning system, the accepted odour threshold is approximately ten times the TLV-TWA. The odour safety factor (TLV/odour threshold) has been calculated as 0.11, and the material has been assigned an odour safety elassification "E" to suggest that less than 10% of attentive persons can detect the gas at a concentration corresponding to its TLV [43]. 

A short-term exposure limit (ceiling vaiue for any 15 min period) has been proposed by NIOSH as 0.2 p.p.m. [1484,1486,1893], and by HSE as 0.06 p.p.m. [917b,917c]. The long-term occupational exposure limits should not be extrapolated to their numerically equivalent concentration-time values [935]. For exposure to phosgene at the TLV of... 

No toxicological data have been recorded for COBrF, and no Occupational Exposure Limits have been recommended. Although it is undoubtedly an irritant with a lethai capacity, it is unlikely to be as poisonous as phosgene. It is unlikely to be flammable. COBrF is not a commercially available substance, and it is not included in the European inventory of existing chemical substances (EINECS) [602a]. 

Phosgene is said to be probably the most poisonous gas used in industry. However, hydrogen sdenide is probably a more poisonous gas and methyl isocyanate is certainly a more poisonous vapor (bp 39 °C). Bis(chloromethyl) ether is more poisonous in the chronic sense (Occupational Exposure Limit, OEL, 1 ppb). Phosgene might, therefore, be more correctly described as the most poisonous gas used in any significant volume in industry [1],... 

The Occupational Safety and Health Administration permissible exposure limit for phosgene is 0.1 ppm. The National Institute for Occupational Safety and Health immediately dangerous to life and health value is 2 ppm. The California Environmental Protection Agency chronic inhalation reference exposure level is 0.0003 mgm. The US Army general population limit is 0.0025 mg m. ... 

COMPARATIVE NATIONAL EXPOSURE LIMITS FOR PHOSGENE IN OCCUPATIONAL AIR... 

IDLH (Immediately Dangerous to Life and Health, National Institute cf Occupational Safety and Health) (NIOSH, 2010) represents the maximum concentration from which one could escape within SOmin without any escape-impairing symptoms, or any irreversible hmlth fffects. The IDLHfor phosgene is based on acute inhalation toxicity data in humans (Diller, 1978). NIOSH REL-STEL (Recommended Exposure Limits—Short Term Exposure Limit) (NIOSH, 2010) is dffined analogous to the ACGIH TLV-TWA. 

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