In chemistry laboratories, fume hood is a large piece of scientific equipment that is commonly found. It is designed to limit a person’s exposure to hazardous fumes. There are two main types of unit exist which are ducted and recalculating. Basically, the principles for all units are same in which air is drawn in from the front of the cabinet by a fan and expelled either outside the building, or made safe through filtration and fed back into the room. In recent years, laboratory fume manufacturers have developed and introduced energy-efficient low flow or high performance fume hoods designed to maintain or improve operator protection while reducing expensive HVAC operating costs.
Perchloric acid unit is featured by a waterwash system in the ductwork. Due to Perchloric acid fumes settle and form explosive crystals, it is vital the ductwork is cleaned internally with a series of sprays.Waterwash unit fume hoods have an internal wash system that cleans the interior of the unit, to prevent a build-up of dangerous chemicals. Scrubber unit fume hoods absorb the fumes through a chamber filled with plastic shapes, which are doused with water. The chemicals are washed into a sump, which is often filled with a neutralizing liquid. The fumes are then dispersed of in the conventional manner