The all-steel fume hood is the primary piece of laboratory ventilation equipment. The laboratory fume hood is an important piece of equipment for safeguarding laboratory operators hazardous chemical agents, it is also a must for protecting improving the operator's environment for ensuring product safety environmental safety. Laboratory ventilation is an integral part of laboratory design. In order to make laboratory workers do inhale swallow some toxic, pathogenic toxicity of unknown chemicals organisms, the laboratory should be well ventilated. To prevent the absorption of some vapors, gases particles (smoke, soot, dust aerosols), contaminants must be removed by means of all-steel fume cupboards, fume hoods local ventilation.