Lab Safety: Pumping Flammable Liquids

In terms of lab safety, pumping flammable liquids can create hazardous conditions. Both fire and explosions can result if safe handling of materials is not adhered to by lab workers, students, and researchers. Examples of liquids that are flammable include ethyl ether, acetone, and benzene. Combustible liquids include acetic acid, formic acid, and formalin.

When flammable and combustible liquids flow, they may create a buildup of static electricity. To reduce the hazard levels, follow these five general safety guidelines.

1) Always use a metallic pump with air-driven or explosion-proof (XPRF) motor.

2) Make sure all components are metal. Plastic can build up static charges and cannot be grounded.

3) Electrically ground the operator and all pump components including motor (even if air-driven), inlet and discharge piping, hose clamps, holding tank, and receiving tank.

4) Avoid splashing liquids—splashing generates static electricity that can result in ignition or explosion.

5) Avoid isolated conductors, such as a metal nozzle at the end of plastic discharge tubing.

Some explosion-proof electric motors have a manual overload reset feature which eliminates the danger of automatic restarting.

Using Personal Protective Equipment

When handling flammable liquids, make sure to use the necessary personal protective equipment, including eye protection, hand protection, body protection, and lung or respiratory protection. Typically, this means goggles, chemical-resistant gloves, coveralls, and perhaps a respirator. OSHA recommends both "eye and face protection when exposed to liquid chemicals, acids, or caustic liquids, chemical gases or vapors." Also, those "whose work involves exposure to hot substances or corrosive or poisonous materials must have protective gear to cover exposed body parts, including legs and feet."