Occupational exposure limit 4.31

Exposure to formic acid vapor causes irritation of the eyes and respiratory tract. The TLV/TWA occupational exposure limit is 5 ppm (40). Self-contained breathing apparatus should be used when there is a risk of exposure to high vapor concentrations. 

Guidance Note EH40/96, Occupational Exposure Limits, Health and Safety Executive, Her Majesty s Stationery Office, London, 1996. 

Other toxicological effects that may be associated with exposure to benzyl chloride based on animal studies are skin sensitization and developmental embryo and/or fetal toxicity. A 1980 OSHA regulation has estabhshed a national occupational exposure limit for benzyl chloride of 5 mg/m (1 ppm). Concentrations of 160 mg/m (32 ppm) in air cause severe irritation of the eyes and respiratory tract (68). 

Do workplace exposures comply with occupational exposure limits or applicable regulatory limits, if they are more stringent If no, explain. 

Do employee exposures to hazardous agents exceed applicable occupational exposure limits, including those of the ACGIH and the applicable local regulatory authority If yes, explain. 

Does the toller rely upon respiratory protective equipment to maintain employee exposures below applicable occupational exposure limits If so, for what materials Explain. 

The toxicity of a substance is its capacity to cause injury once inside the body. The main modes of entry into the body by chemicals in industry are inhalation, ingestion and absorption through the skin. Gases, vapours, mists, dusts, fumes and aerosols can be inhaled and they can also affect the skin, eyes and mucous membranes. Ingestion is rare although possible as a result of poor personal hygiene, subconscious hand-to-mouth contact, or accidents. The skin can be affected directly by contact with the chemicals, even when intact, but its permeability to certain substances also offers a route into the body. Chemicals accorded a skin notation in the list of Occupational Exposure Limits (see Table 5.12) are listed in Table 5.2. Exposure may also arise via skin lesions. 

Table 5.2 Materials with an Sk notation in list of Occupational Exposure Limits ...

Threshold limit values (USA) Occupational exposure limits (UK) Air odour... 

Threshold Limit Values or Occupational Exposure Limits (preferably with reference to their interpretation, i.e. not as safe levels). 

Control of Substances Hazardous to Health Regulations (COSHH). Guidance on Setting In-House Occupational Exposure Limits (Regulation 7 (1990)... 

Work with asbestos insulating board (superseded by EH 71j Ozone health hazards and precautionary measures Occupational exposure limits (annual)... 

Summary cntena for occupational exposure limits 1996 (with updates/changes 1997, 1998, 1999) Tnmethylbenzenes criteria document for an OEL Pulverized fuel ash cntena document for an OEL N,N-dimethylacetamide cntena document for an OEL... 

International Labor Office, 1991. Occupational exposure limits for airborne toxic substances. Occupational Safety and Health Series, No. 37. International Labour Office, Geneva. 

Thus, there is a clear need to establish the relationship between the health effects of hazardous chemical agents in the environment and the level of occupational exposure to the body by means of an occupational exposure limit, in which a reference figure for the concentration of a chemical agent is set. In fact, occupational exposure limits (OELs) have been a feature of the industrialized world since the early 1950s. They were introduced, primarily in the United States, at a time when measures to prevent occupational diseases were considered more beneficial than compensating victims, and in this sense OELs have played an important part in the control of occupational illnesses. 

Binding occupational exposure limit values reflect feasibility factors related to social acceptability. When the results of environmental monitoring have to be compared with OELs, factors that influence exposure and that entail preventive policies are considered. For these values member states shall establish a corresponding national binding occupational exposure limit value based on but not exceeding the community limit value. That is, a binding limit means a minimum requirement. 

An indicative limit value is a more common type of limit that reflects expert evaluation based on scientific data where it is possible to identify the highest level of exposure along with the corresponding reference time period for which one can have confidence that there will be no adverse effects on health. For any chemical agent for which an indicative occupational exposure limit value is established at the community level, member states shall establish a national occupational exposure limit value, taking into account the community limit value and determining its nature in accordance with national legislation and practice. 

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