Threshold limits airborne contaminants

Threshold Limit Value TEV) Maximum values of concentrations of airborne toxic contaminants, listed by the American Conference of Governmental Industrial Hygienists (ACGIH), regarded to be safe for 8 hours per day exposure. 

Filter samples can be prepared to airborne workplace concentrations by spiking each filter with aqueous solution containing elements with concentrations gravimetrically traceable to ultrapure metals or stoidiiometricaUy well defined oxides. The amormts correspond for some of the materials to current threshold limit values of contaminants in workroom atmospheres provided that the simulated filter has been exposed to one cubic meter of air. The certified values are based on a gravimetric procedure, i.e. weight per volume composition of the primary reference material dissolved in high purity sub-dis-tiUed acids. The National Institute of Occupational Health in Oslo, Norway, has produced several batches of such materials certified for 20 elements. Additionally, information values are reported for four other elements see Table 6.2. 

OSHA. 1998b. Occupational Safety and Health Administration. Appendix A. Threshold Limit Values of airborne contaminants for construction. 29 CFR 1926.55. 

Threshold Limit Values of Airborne Contaminants", Federal Register, 1979, 44, 8855. 

Threshold Limit Values of Airborne Contaminants, adopted by ACGIH for 1969, American Conference of Governmental Industrial Hygienists, 1014 Broadway, Cincinnati, Ohio 45202. 

Exact Solution for Mixtures of N Components With Addictive Effects and Different Vapor Pressures, Threshold Limit Values of Airborne Contaminants and Physical Agents, pp. 43-45, ACGIH, Cincinnati, Ohio, 1971. 

Exposure Limits PELs and TLVs. Threshold limit values (TLVs) were developed in the 1940s, long before the existence of OSHA. The TLV is defined as the airborne concentration of a contaminant to which it is believed that most workers may be repeatedly exposed, day after day, without developing adverse health effects. Developed and maintained by the American Conference of Governmental Industrial Hygienists (ACGIH), these values have been determined based on industrial experience and animal and human studies. 

Several organizations recommend limits of exposure to airborne contaminants in the workplace. These include the Occupational Safety and Health Administration (OSHA), the National Institute for Occupational Safety and Health (NIOSH), and the non-governmental organization, American Conference of Governmental Industrial Hygienists (ACGIH). The threshold limit value (TLV) for a substance is defined as the concentration level under which the majority of workers may be repeatedly exposed, day after day, without adverse effects. The TLV recommendations are given in two forms ... 

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