Physiological hazards

Industrial refractories are by thek very nature stable materials and usually do not constitute a physiological hazard. This is not so, however, for unusual refractories that might contain heavy metals or radioactive oxides, such as thoria and urania, or to bkiders or additives that may be toxic. 

The acrylate esters are more physiologically hazardous than their saturated homologues. They are usually lachrymalors and irritants, and their loxicities decrease with increasing molecular weight. 

Limiting workers exposure to released fuels (if the fuels present a physiological hazard). 

At ambient temperature and pressure hydrogen is colorless, odorless, tasteless and nontoxic. However, leaks of hydrogen (or any gas for that matter) can displace oxygen and act as an asphyxiant. Any atmosphere with less than 19.5% oxygen by volume in considered oxygen deficient and asphyxiation can lead to physiological hazards. 

Equipment inexpensive. 7 Expensive equipment necessary. Severe physiological hazard. 8 Small volumes may be hand-mixed. 

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