Background: Hazardous chemical agents in the welding operation are a mixture of metal fumes and toxic gases, the inhalation of which causes adverse health effects among welders. The emission of gases in the workplace is a logical cause for concern regarding the potential development of respiratory disease. The aim of the present study was to determine the concentration values of gases discharge...

9. REFERENCES Abu-Hilal AH, Khordagui HK. 1993. Assessment of tar pollution on the United Arab Emirates beaches. Environ Int 19:589-596. ACGIH. 1986. Documentation of the threshold limit values and biological exposure indices. American Conference of Governmental Industrial Hygienists, Cincinnati, OH. ACGIH. 1992. Threshold limit values for chemical substances and physical agents and biological ...

background : few studies have focused on syndromic data to determine levels of alarm thresholds to detection of meningitis outbreaks. the purpose of this study was to determine threshold levels of meningitis outbreak in hamadan province, west of iran . methods : data on both confirmed and suspected cases of meningitis (fever and neurological symptom) form 21 march 2010 to 20 march 2012 were use...

in this study, the fatigue behavior of alloy steels with different hardness values was tested. results showed that the fatigue limit increases by the increment of hardness up to 400 vickers whereas it drops when the hardness value exceeds 400 vickers. fractographic observations using scanning electron microscopy revealed non-metallic inclusions as the dominant fatigue crack initiation sites. by...

This paper analyzes the role of threshold limit values (TLVs) in national air pollution policy during the 1980s, a period in which the Environmental Protection Agency (EPA) sought to delegate to individual states the authority to evaluate and regulate airborne toxic substances. We focus on 20 carcinogens and 11 substances with non-genotoxic health effects that were regulated by local air toxics...

Objective: To define threshold limit values and legally binding occupational exposure limits. Data Sources: Review of suitable literature. Study Selection: Studies based on detailed descriptions and/or measurements of airborne allergenic dust, total allergens, or even key allergens were selected. Results: Prevalences of IgE-mediated sensitization and occupational asthma are related to the aeroa...

The use of immunoassays has facilitated the measurement of high molecular weight sensitizers, usually protein molecules, in the picogram and nanogram per cubic meter range. This facilitated the evaluation of exposure response relationships for bakery workers, exposed to wheat allergens and fungal alpha-amylase and other groups exposed to other allergens such as laboratory animal workers. The ap...

introduction blue light is a part of the spectrum with the highest energy content, which can reach the retina. the damage that it can cause to the retina is called photochemical or blue-light retinal injury. for the retinal injury assessment of the photochemical and aphakic retinal hazards in the wavelength range of 300-700 nm, use of effective spectral radiance limits (w.m-2.sr-1) seems to be ...