Which energy categories are included in OSHA's lockout/tagout rule?

• A. Electrical, mechanical, hydraulic, chemical, thermal, kinetic, or other
• B. Electrical energy only
• C. Hydraulic and mechanical only
• D. Chemical energy only

Answer: (A)

The idea being tested is that OSHA’s lockout/tagout rule covers all forms of energy that could pose a hazard when equipment is serviced, not just electrical energy. The standard identifies energy sources as electrical, mechanical, hydraulic, pneumatic, chemical, thermal, or other energy, and requires these to be controlled before work begins. That means you must recognize and isolate every energy form that could move, release, or energize parts of the machine—including stored energy in springs, gravity, or compressed fluids.

Because of this broad scope, the best answer lists multiple energy categories and includes “other” energy forms. Focusing on a single energy type (like electrical alone) wouldn’t meet the rule’s requirement to control all potential hazardous energy.