Reference the infographic at the right: Releasing the load causes
it to drop, converting potential energy to kinetic energy. It's the
harmful transfer of energy at impact between an object and the
worker that can cause injury. Note: It's the "harmful transfer of
energy" that is always the direct cause of injury in an accident
event.
6. What are the two basic states of energy?a. Physical and electrical energy
b. Thermal energy and actual energy
c. Potential energy and kinetic energy
d. Kinetic energy and expendable energy1.7 Types of Energy
It's important to understand that electricity is not the only form of hazardous energy employees may
encounter during lockout/tagout. Main energy sources that supply power to the entire machine or
equipment may be electrical, but secondary energy sources such as pneumatic or mechanical energy
may still be stored with the potential to cause injury. One of more of the following types of energy may
require de-energization to completely isolate the equipment.
- Chemical: Liquids, such as gasoline, diesel, benzene, acids, and caustics. Gases, such as propane,
natural gas, and methane. Solids, such as fertilizer, wet and dry cell batteries, and combustible
dust. - Electrical: Alternating (AC) and direct (DC) currents. Includes equipment and conductors at both
household and industrial-voltages, photovoltaic systems, circuit breakers, transformers,
capacitors, inverters, motors, and hybrid vehicles. - Gravitational: Objects such as hoisted vehicles, raised dumpster lids, objects supported by a
crane, and elevated dump truck beds.
Potential energy is converted to kinetic energy.