Exposure level, maximum, various

Safety Standards. Protection from laser beams involves not allowing laser radiation at a level higher than a maximum permissible exposure level to strike the human body. Maximum permissible exposure levels for both eyes and skin have been defined (55—57). One of the most common safety measures is the use of protective eyewear. Manufacturers of laser safety eyewear commonly specify the attenuation at various laser wavelengths. Under some conditions safety eyewear has been known to shatter or to be burned through (58), and it is not adequate to protect a wearer staring directly into the beam. 

Contact with liquefied chlorine will definitely cause frostbite, bums, ulcerations, or necrosis. A concentration of 1,000 ppm by volume of chlorine in air is rapidly fatal after a few deep breaths. The least amounts that will result in throat irritation and coughing are 15 and 30 ppm respectively. The maximum level that can be inhaled for one hour without serious effects is 5 ppm. Concentrations of 3 to 5 ppm by volume in air are readily detectable. The effects of different concentrations of chlorine on humans are shown in Table 33.5. The maximum exposure levels of chlorine according to various guidelines are shown in Table 33.6. 

One of the most significant laser safety standards is that developed by the Z-136 committee of the American National Standards Institute (ANSI) (55). Although it is voluntary, many organi2ations use the ANSI standard. It contains a number of items including a recommendation for maximum permissible levels of exposure to laser radiation for various wavelengths, exposure durations, and different parts of the body separation of lasers into four different classes according to the level of ha2ard they present and recommendation of safety practices for lasers in each of the classes. 

Uncertainties assessed at Tier 2 (deterministic) generate alternative point estimates for exposure and may be communicated in various ways, depending on the particular methods used for sensitivity analysis. As a minimum, this should identify which sources of uncertainty have been treated at Tier 2, state and justify the alternative quantitative estimates used for each one (e.g. minimum, maximum and most likely values), present exposure estimates for those combinations of alternative estimates that are considered plausible and state and justify any combinations of estimates that are considered implausible. In addition, it will be useful (especially if upper estimates exceed levels of concern) to show which of the quantified uncertainties have most influence on the outcome. 

Higher levels of exposure have been found in other occupational settings. Representative information on inhalation exposures of 2-butoxyethanol in various occupations in the United States is summarized in Table 5-1. Tliese data indicate that personal exposures above the NIOSH REL of 5 ppm (24 mg/m ) have been found in silk screening, printing, furniture production, and asbestos/mastic removal, with maximum exposures of 36, 8.3, 9.9, and 22 ppm (174, 40, 48, and 106 mg/m ), respectively. It should be noted that the OSHA PEL, the... 

Abstract. Nickel and its compounds are widely used in various manufactures such as machine-building plants, galvanic industry, metallurgy and others. The basic chemical factors in the galvanic industry are aerosols of sulfate and chloride of nickel, which concentration in air of the working zone did not exceed the maximum permissible level Influence of solutions on skin is limited by the use of individual protective devices. The analysis of condition of reproductive health of working women exposed to nickel has not revealed any statistical connection between morbidity and exposure to this metal. Prevailing diseases were a climacteric syndrome, hysteroptosis and colpoptosis. Activation humoral immunity and the sensibility to nickel were found in workers exposed to nickel... 

The tentative tolerable daily intakes proposed for certain metals provide a guideline for maximum tolerable exposure. In the case of essential elements, these levels exceed the daily requirements, but this should not be construed as an indication of any change in the recommended daily requirements. In the case of both essential and nonessential metals, the tentative tolerable intake reflects permissible human exposures to these substances as a result of natural occurrence in foods or various food processing practices, as well as exposure from drinking water. 

The saltwater aquatic life protection criterion of 4.5 tLg Cd/L seems adequate to prevent death, but will not prevent potentially deleterious physiological effects, including dismpted respiration in crustaceans and teleosts. Incidentally, at 5.0 ttg Cd/L, the lowest concentration critically examined, oysters biomagnify ambient levels to concentrations hazardous to human consumers and possibly other animal consumers. The maximum allowable concentration (MAC) in saltwater during a 24-h period was recommended as 59.0p,g/L (Table 5.2). However, death of various species of marine crustaceans was reported at 60.0 p,g Cd/L after exposure for 6 weeks and at 14.8-19.5 ttg/L after 23-27 days. Furthermore, a MAC of... 

The differentials in the equation for hedonic labor market equilibrium, daldn and d ildn, describe how firms and workers match at the various degrees of exposure to work-related health hazards. There are three first-order conditions for the firm s maximum profit. We totally differentiated the three necessary conditions for maximum profit in (5.2)-(5.4) with respect to p and n to solve for the equilibrium pairings of firms and workplace safety levels, d x dn. Next, we re-arranged equation (5.5), the necessary condition for labor market equilibrium, to solve for da/dn, how workers sort against levels of injury risk. The differential equations of interest have the general expressions... 

The various sections of the CAA, overall, allow consideration of the role of nonambient air levels of lead in quantifying rationales for setting primary and secondary NAAQS. The 1978 NAAQS value of 1.5 xg/m (quarterly maximum arithmetic average) as the primary and secondary standards for Pb derived from multimedia analysis of contributions to overall biomarkers of exposure, i.e., PbB, and the details are presented in a later chapter on air Pb regulation. 

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