Engineering Controls

Engineering controls are used to remove a chemical hazard, or to place a barrier between the worker and the chemical hazard. Well-designed engineering controls can be highly effective in protecting workers. The initial cost of engineering controls can be high, but over the longer term, operating costs are frequently lower, and in some instances, can provide a cost savings in other areas of the process. Engineering controls reduce or eliminate exposure to chemical or physical hazards through one of the following methods:

• Elimination of a hazardous technique, process, or material
• Substitution of a less hazardous technique, process, or material for a more hazardous one
• Segregation of people from hazards
• Enclosure of hazards
• Ventilation of the workplace and the source of contaminants
• Repair or replacement of faulty equipment or machinery

Mechanical ventilation is another engineering control to reduce chemical exposure. Ventilation can either be general (dilution) or local (exhaust) systems.

General ventilation forces fresh air into an area and dilutes contaminants. This provides a continual supply of fresh air. It is important to note that pure oxygen must never be used for ventilation purposes as it increases flammability risks. General ventilation works best when air contaminants are widely dispersed and toxicity and concentration levels are low. General ventilation can be simply achieved through the use of fans to blow fresh air inside the work site.

Local ventilation removes contaminated air. The contaminated air removed from the work space must be discharged into the open air, well clear of the source of intake air. Local ventilation works best when air contaminants are generated at a single source and there are high concentrations of toxins that need to be removed. Examples of local ventilation include exhaust hoods and fans set to pull or blow air out of the worksite.

To learn more about Industrial Chemical Hazards visit our Industrial Chemical Hazards & Toxic Substances Online Training web page.