EHS has developed electrical safety guidelines which are designed to prevent employees and students from exposure to hazardous, electrical energies. Details of these guidelines, along with additional information, can be found in the Electrical Safety Manual.
The most hazardous electrical situation an individual can be exposed to is an arc flash. This may occur from a variety of causes including:
- Coming close to a high energy source with a conductive object
- Creating a spark which can ignite an arc flash
- Equipment failure
- Breaks or gaps in insulation
Exposure to an arc flash can result in a shock, severe burn and death. A variety of sources were used in development of these guidelines including OSHA, and primarily the NFPA 70-E standard. Working on de-energized equipment is the preferred work practice. However, this is not always possible. Training is a major aspect of electrical safety. Coupled with improved safety equipment and procedures the end result is improved safety and the development of Qualified Electrical Workers.
Qualified Electrical Worker
Through a combination of experience and training an individual may be considered a qualified electrical worker. A qualified worker must be able to demonstrate knowledge of a proficiency in the following.
- National electrical code
- Lockout/tagout procedures
- Electrical safety procedures
- On the job experience
- Skills necessary to determine the nominal voltage of exposed live ports
- Approach distances specified in the Electrical safety Guidelines
- Selection and use of PPE and safety equipment
- Basic CPR and AED
- Arc flash safety
Only a Qualified Electrical Worker is allowed near energized electrical parts.
A comprehensive Lockout/Tagout procedure is vital to any electrical safety program. The guidelines cover in depth all the aspects of the lockout/tagout program.
The basic elements are:
- Locating and labeling energy sources
- How equipment is de-energized
- Verifying the circuit cants be restarted
- Voltage testing
- Applying and removing lockout/tagout devices
Lockout devices are employee specific and can only be removed by the individual who put it in place.
An energized electrical work permit is required for all work on voltages of 240 and higher. The purpose of this permit is to make sure that all appropriate safety precautions are taken prior to energized electrical work. Permits are originated by a qualified electrical worker.
Arc flash clothing and protective equipment is required when working with energized electrical equipment. Clothing ranges from untreated cotton up to flash resistant pants with shirt. The type of clothing and equipment required is based upon the amount of potential energy released in the event of an arc flash.