White Paper: Learn More About Fume Hoods

The laboratory's degree of exposure to toxic contaminants is an important consideration when selecting a fume hood. The concentration of contaminants in the actual breathing zone of the operator should be kept as low as possible. Two fume hood issues that impact the concentration of contaminants are face velocity and containment.

Regulatory compliance agencies and other advisory groups have established guidelines relating to the exposure limits of various chemical reagents. These exposure limits are identified as American Conference of Governmental Industrial Hygienists (ACGIH) Threshold Limit Values (TLV) or Occupational Safety and Health Administration (OSHA) Permissible Exposure Limits (PEL). Threshold Limit Values refer to airborne concentrations of substances and represent conditions under which it is believed workers may be repeatedly exposed day after day without adverse effect.