Stored energy can be mechanical, gravitational, hydraulic, chemical, or pneumatic and refers to the energy stored in machines and equipment. Stored energy hazards exist because stored energy can be released accidentally and potentially cause serious injury.

Unfortunately, hazards related to stored energy are often misunderstood and not easily recognized. And according to the U.S. Department of Labor, nearly 10% of serious accidents are associated with failure to control stored energy.

What are stored energy hazards?

There are many stored energy sources in equipment, and they can all hold hazards if the energy is released inadvertently. For example:

  • Compressed air cylinders
  • Pressure washers
  • Springs
  • Winches
  • Hydraulic systems
  • Pneumatic systems
  • Electrical systems
  • Coiled steel cables
  • Explosive devices such as dynamite or TNT

In hydraulic or pneumatic systems, fluid pressure can reach up to 1000 pounds per square inch! In extreme cases, these fluids have been known to flash into steam with explosive force. And during the servicing and maintenance of machines and equipment, an unexpected startup can release stored energy and cause serious injury.  

The stored energy can also refer to moving parts that come into contact with each other. For example:

  • Mechanical energy hazards from the moving parts of equipment
  • Gravitational stored energy hazards, resulting in falls from heights

Stored Energy-related Injuries

The stored energy can be the cause of serious injuries or even death. The following are the most common types of injuries associated with stored energy hazards:

  • Electrocution
  • Burns
  • Crushing
  • Cutting
  • Lacerating
  • Amputations
  • Fractures

The following are more specific examples of stored-energy related injuries:

  • Electric shock from mishandling industrial batteries
  • Electric shock from mishandling powered equipment
  • Chemical burns from an accidental chemical reaction
  • Being caught in moving equipment

The Control of Hazardous Energy (Lockout/Tagout)

The Occupational Safety and Health Administration recognizes the risks that stored energy poses to workplace safety. They have created a standard that addresses the practices and procedures necessary to disable machinery or equipment and prevent the release of hazardous energy, mainly when employees perform servicing and maintenance activities.  

Lock out - tag out (LOTO) refers to the safety procedures ensuring that potentially dangerous machines are shut off properly and cannot be started up again before the maintenance or repair work has been completed. These precautions help prevent machines' accidental startup while in a hazardous state or while a worker is working directly with it. The standard also requires the following:

Hazardous energy sources should be "isolated and rendered inoperative" before work begins.

Isolated power sources should be locked and tagged with a lock identifying the worker who locked them. The worker holds the key for the lock, ensuring they are the only ones who can remove the lock and start the machine. Some of the most critical LOTO requirements outlined by OSHA are:

  • Develop, implement, and enforce an energy control program
  • Use lockout devices for equipment that can be locked out
  • Ensure that new or overhauled equipment is capable of being locked out
  • Develop, implement and enforce an effective tagout program if machines or equipment are not capable of being locked out
  • Develop, document, implement and enforce energy control procedures
  • Ensure that lockout/tagout devices identify the individual users
  • Inspect energy control procedures at least annually

These standards can be used as the outline for an inspection program. With The Checker, you can ensure nothing is overlooked. Contact us to learn how our software for any kind of inspection program include lockout / tagout. 

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