Guidance for Cleaning and Disinfecting of Electrical Equipment

The unprecedented impact of COVID-19 has driven careful attention to the role of our physical environment in keeping us healthy. Cleaning of all surfaces in homes, schools and public buildings, commercial locations and workplaces has become a matter of routine. 

Of particular concern with COVID-19 is the period of time that the active virus may remain viable on surfaces. This can lead to an increased risk of transmission. As a result, additional measures are being employed to more assuredly disinfect these surfaces, some of which have typically only been employed by professionals in special installations. It is therefore essential that, in an effort to address one safety concern, we are careful not to introduce another.

If not properly performed, cleaning and disinfection of electrical equipment may result in hazards or unsafe conditions with the equipment.

UL Solutions, in the interest of providing guidance on how to safely clean and disinfect electrical equipment, has compiled this list of best practices:

What to do:

• Follow established safety precautions for working with electrical equipment, including de-energizing equipment when possible and wearing any specified personal protective equipment, e.g., for hands and face.
• Follow the original equipment manufacturer (OEM) instructions for specific cleaning protocols for equipment or consult the OEM for guidance if such instructions are not available. 
• Consult available publications:
  • U.S. Occupational Safety and Health Administration COVID-19 Page
  • National Fire Protection Association Standard for Electrical Safety in the Workplace, NFPA 70E
  • National Electrical Manufacturers Association (NEMA) COVID-19 Cleaning and Disinfecting Guidance for Electrical Equipment, NEMA GD 4-2020
• If a form of liquid or atomized solution is approved for use by the equipment manufacturer, carefully follow the instructions, using only the specified solution and applicator, taking all specified pre-application preparations e.g., closing openings before application on the de-energized electrical equipment. Allow the cleaning/disinfection solution to dry prior to reenergizing the equipment.
• Allow any surfaces that may be hot to cool prior to cleaning.

What not to do:

• Do not spray liquids of any kind into electrical equipment, especially when energized.
• Do not immerse electrical equipment in liquids unless specifically permitted, as indicated by equipment markings or instructions of the original equipment manufacturer.
• Do not apply liquid or corrosive substances on to electrical equipment unless both the electrical equipment and substance to be applied are specifically approved for that use. Similarly, do not fog equipment with disinfectant unless specifically approved for that use. These media may cause electrical shock or arcing injury hazards. They may also result in degradation of components or materials in electrical equipment, leading to hazards immediately or over the equipment life.
• Do not direct ultraviolet (UV) radiation sources at electrical equipment surfaces unless specifically approved for the purpose, e.g., sunlight resistant (UV-A and UV-B only), and only when professionally applied following UV-safety operating safeguards. Even if the equipment may withstand the treatment, this process might expose the operator to a radiation hazard (erythema and optical injury) and shall be approved by a designated safety officer or industrial hygienist first. UV radiation also may degrade insulating or other materials used in equipment and produce hazards and should only be used where approved by the original equipment manufacturer.
• Do not place covering materials on or over surfaces or electrical equipment openings. Such materials may act as thermal insulation or barriers, causing electrical equipment to overheat.
• Do not remove or deface equipment markings by any cleaning or disinfection action.

For information on COVID-19 and guidance on health safety precautions to be taken, consult the U.S. Centers for Disease Control and Prevention (CDC).