Need to vent? Must be toxic fumes

Need to vent? Must be toxic fumes

Find out what OSHA wants you to do when a chemical bottle warns you to provide adequate ventilation.
Jan 01, 2011

There's one warning that's universal to almost every chemical bottle in your practice: "Use with adequate ventilation." But how do you know if ventilation is adequate? It's time to explore how to guarantee healthy air after a team member cracks the lid on a bottle of noxious, hazardous, or flammable chemicals.


Ventilation can mean filtering and recirculating the air or removing air from the source and exhausting it outside. In the context of chemicals, the term ventilation usually refers to exhaust ventilation so that fumes are transferred outside of the building. This reduces fume concentration to ensure employees don't breathe hazardous levels and flammable fumes don't ignite.


It's difficult to make specific recommendations for practices because layouts differ from facility to facility and fumes differ from chemical to chemical. However, there are a few guidelines most veterinary operations should be following.

For drug handling. Most clinical laboratory and pharmacy operations are sufficient with a forced-air heating or air conditioning system. However, practices that conduct chemotherapy or microbiology procedures require specialized fume-hood exhaust systems. If there's no forced-air system in place, then an engineered air-to-air heat exchanger is recommended. Consult a heating professional for specifics.

For bathing, dipping, or insecticide application. These areas should be equipped with an exhaust fan that moves roughly 100 to 500 cubic feet of air per minute. The fan should be mounted directly over the tub area to draw fumes away from the worker and reduce the concentration in the breathing zone. Large area fans used in kennels for odor control and cooling are insufficient for chemical applications—they don't move enough air from the right locations. And sometimes team members turn off these large fans to prevent the loss of heating or cooling.

For radiography involving chemicals. The radiography dark room needs a small exhaust fan that moves 60 to 100 cubic feet per minute. Additionally, when the room isn't in use, the door should be left slightly open or a dark room vent should be left on to draw in clean air as it vents the fumes.

For anesthesia. Exhaust fans are also necessary in anesthesia induction and recovery areas. Studies have shown that even when a proper scavenging system is in place, mask inductions and patient recovery procedures can raise the gas levels in the air to five times the allowable limits. The best solution is to separate the recovery area from the treatment and surgery area and install an exhaust fan. Plus, mask inductions should be the exception, not the rule.

Phil Seibert, CVT, is an author, speaker, and consultant with SafetyVet in Calhoun, Tenn. Send questions or comments to