Controlling Energy Sources

Headlines: "Workers killed when Machine Explodes", "Man Killed when Power Turned On", "Train Derails after Rolling Down Hill". What do all of these headlines have in common? Each tragic incident resulted from uncontrolled energy sources. Another thing in common is that each tragedy may have been prevented by simply recognizing the energy sources that were present and then taking action to control them.

Why should energy sources be controlled? The answer is obvious: Safety of the workforce! Preventing deaths and injuries is paramount and our nation's watchdog, the U.S. Occupational Safety and Health Administration (OSHA), has taken numerous steps to mandate the control of energy sources. OSHA issued the Lock out/Tag out (LOTO) regulation, found in 29 CFR 1910.147, and better known as "Control of Hazardous Energy". OSHA also has regulations concerning the handling of flammable and combustible liquids and the grounding and bonding of equipment in hazardous locations found in 29 CFR 1910.307 and 1910.106, respectively. National Standards from the National Fire Protection Association (NFPA) also address the control of energy in Standard 77-Recommended Practice on Static Electricity. It behooves responders to be well versed in these regulations and standards because of the interface with private business and also to increase their own safety, reduce their own risk, and to better control damage to property.

Working around energy sources can be compared to swimming with sharks; the risk of injury is extremely high merely because of the proximity of the hazard. A few solutions exist; the worker/swimmer can be protected with special clothing or the energy/shark can be controlled or contained. Each solution has its advantages and disadvantages but merely being aware of a hazard is an important start.

All responders need to be vigilant in watching for and identifying energy sources that can harm people. Responders also need to look around corners and anticipate the energy sources that could enter into any emergency. This is called "situational awareness" or being aware of your surroundings and then taking action to safeguard all personnel. Actions may include employing your resources such as the assistance of private industry.

An easy mnemonic to remember the energy sources that can harm is "TRACEM".

Each letter stands for;

  • Thermal
  • Radiation
  • Acoustic
  • Chemical
  • Electrical and Etiologic
  • Mechanical

Thermal hazards include both heat and the absence of heat (cold). It may include fire, steam, molten metals, heat stress, cryogenics, refrigeration systems, exothermic and endothermic reactions, and compressed, liquefied gases.

Radiation hazards include both ionizing and non-ionizing radiation such as alpha, beta, gamma, and infrared, ultraviolet, and microwave radiation, respectively.

Acoustic hazards include the complete sound spectrum along with noise.

Chemical hazards include reactive, corrosive, flammable, oxidizable, pyrophoric and explosive materials.

Electrical hazards include ground fault problems, arcing, stored electrical devices, and static electricity.

Etiologic hazards include biological concerns of virus's, bacteria, fungi, and maybe even contaminated sharps.

Mechanical hazards include gravity concerns, potential and kinetic energy sources, hydraulic and pneumatic pressure.

Gravity is a special and constant concern that always needs to be addressed. Falls are very injurious but falling objects are equally dangerous. Addressing the potential for all objects to be influenced by gravity is a number one priority. For instance, how many responders chock the wheels of vehicles that are involved in an emergency? Numerous examples of vehicles rolling away at emergencies can be cited. The basic rule is to chock anything that has wheels. This should include automobiles, trucks, heavy equipment, and even rail cars. Ordinary vehicle chocks will work for most applications but the rail industry has special wheel chocks for rail cars. Make no assumptions on when gravity will take over and turn potential (object at rest) into kinetic (object in motion) energy.

The Lock-out/Tag-out regulation is another concept that responders need to apply at emergencies because of its safety aspects. LOTO isolates energy sources and de-energizes all equipment in order for personnel to work safely nearby. LOTO mandates that the equipment and start-up switches have locks applied to prevent the premature or accidental activation of the equipment. LOTO also mandates that these actions be communicated to others by signage or tags that describe who did the shut down and their intent. LOTO's are designed to save lives by isolating energy and then communicating the actions taken to others. Even though private industry is mandated to conduct LOTO all responders should be knowledgeable on the system and how to employ it themselves. In fact, many response agencies across the country have LOTO training and kits on their response vehicles. One last item regarding equipment and machines for all responders to be cognizant of is that back-up energy sources may exist that also need to be de-energized. Explore these possibilities with private personnel on locations of emergencies.

Grounding and bonding are methods of controlling static electricity usually in industrial settings involving flammable liquids. However, many response organizations employ grounding and bonding techniques in emergency situations to better control the risk of static electricity igniting flammable environments. One application is when transferring product from a damaged container to another container. Grounding and bonding is not as simple as driving copper rods and then hooking battery cables to the rods on one end and the containers on the other end of the cable. There is much more to safe and proper grounding and bonding than meets the eye. A comprehensive course that examines the science of grounding and bonding, a thorough understanding of the tools and equipment used for the process, and then extensive hands-on activities under the supervision of knowledgeable and experienced instructors is paramount in order to safely conduct grounding and bonding activities on emergencies. One such course can be found at the Transportation Technology Center, Inc. (TTCI)-Emergency Response Training Center (ERTC) in Pueblo, Colorado. Contact is at

In summary, strive to be aware of energy sources at every emergency and then take appropriate actions to control the hazard based on your training and equipment. Also, think ahead and try to anticipate any energy sources that may enter the picture and cause harm. Take the blinders off and remember your 360 degree bubble to maintain safety. Control energy sources at fire scenes, technical rescue, confined spaces, and hazardous materials incidents.

Controlling Energy Sources Checklist

By identifying the possible energy sources at every emergency, responders will be better able to employ strategies to maintain safety. This checklist is designed to prompt personnel to examine the potential energy sources present.