Cover-up equipment is a work practice that can protect workers from contacting energized conductors and is recommended for use on all high-voltage line maintenance and underground tasks. Using cover-up equipment provides maximum protection from electrocution for workers by creating a barrier against the flow of electrical current. A wide variety of cover-up equipment is available to help line workers perform live-line work safely and productively. Cover-up equipment should be used in conjunction with PPE as well as hot sticks when applicable.

Insulating covers are categorized into four types: Cutout Cover, Deadend Cover, Conductor and Insulator Cover, and Pole Covers. All types are constructed, tested, and maintained based on ASTM standards and OSHA regulations. 

Cutout Cover

A cutout cover is used to protect line workers near open-type cutouts that are rated less than 25 kV.  Cutout covers comply with current ASTM D 1049 and ASTM F712 specifications. The flexible type of cutout covers can be used for both overhead cutouts and underground pad-mounted equipment.

Deadend Cover

A deadend cover fits over conductors and insulators. This cover can join to conductor covers and rubber line hoses, thereby extending the protected area. This cover can be installed either using clamp sticks or by hand, using rubber gloves and sleeves. However, use of a combination of both methods is recommended. Acceptable use of this cover is up to 25 kV.

Conductor and Insulator Cover

Conductor and insulator covers can cover up energized power lines and provide maximum protection from electrocution for line workers. These covers can be coupled with deadend covers on one end and line hoses on the other to extend protected areas. The ASTMF712 is used to test specifications for these covers.

Pole Covers

Pole covers are used to protect a line worker when s/he is raising or lowering a pole between lines that are energized. These covers are ribbed to reduce contact points with any energized piece of equipment in order to increase the life span of the cover.

Since the cover-up equipment does not completely eliminate the risk of electrical incidents, the listed standard OSHA guidelines must be followed even when using cover-up equipment. According to OSHA 1910.269(l)(2)(i), at least two employees must be present while any employees perform the following types of work on power lines:

• "Installation, removal, or repair of lines energized at more than 600 volts [OSHA 1910.269(l)(2)(i)(B)]
• Installation, removal, or repair of de-energized lines if an employee is exposed to contact with other parts energized at more than 600 volts [OSHA 1910.269(l)(2)(i)(C)]
• Installation, removal, or repair of equipment, such as transformers, capacitors, and regulators, if an employee is exposed to contact with parts energized at more than 600 volts [OSHA 1910.269(l)(2)(i)(D)]
• Work involving the use of mechanical equipment, other than insulated aerial lifts, near parts energized at more than 600 volts. [OSHA 1910.269(l)(2)(i)(E)]"

Qualified line workers must install cover-up equipment. It serves as temporary insulation between workers and energized lines. Cover-up equipment with phase-to-phase voltage ratings (ASTM Class 00-600V to Class 6-72.5kV) is available for multiple applications. The voltage of two covers cannot be added to achieve higher voltage ratings.

By using cover-up equipment, line workers can work on live lines, eliminating the risk of accidental contact with live parts. Moreover, there is no need to spend time and money to contact utility companies to de-energize lines and to then follow all grounding processes to ensure they are de-energized. Therefore, using cover-up equipment can improve productivity. Generally, when workers feel safe working on live lines, they will be more productive.

Administrative guidelines:

• Two trained and qualified line workers equipped with appropriate PPE must be present for installing or removing the rated covers. A second qualified worker will be required as a safety watch for the worker installing the covers, even with the use of rated cover-ups. All line workers are responsible for checking whether the insulator is appropriate to the extent deployed.
• Insulating covers must be secured if they can move and expose the live parts.
• Cover-up equipment is intended for protection from accidental brush contact only. To prevent accidental contact with the cover and to ensure safety, site supervisors should require and encourage workers to use PPE and keep safe distance, even when working with proper cover-up equipment (OSHA 1910.269(l)(2)).
• The energized part should be covered first, then the nearest conductive parts that are not currently energized but can become energized (e.g., guy wires, cross arms, poles, etc.). The removal process must be done in reverse order.

Maintenance and testing:

• Inspection, maintenance, and testing are integral parts of cover-up applications. The industry has set the standards for in-service care and technical testing of cover-up equipment (ASTM D 1049-88, ASTM F478)
• Covers must be handled carefully to reduce breakage and scratching.
• Cover-up equipment must be inspected daily before each use to ensure there are no holes, tears, ozone cutting, or deep scratches, and to ensure that all standard specifications are met. There is no approved method for repairing cover-up equipment. If they are damaged, they must be replaced.
• It is critical that covers be kept clean, so rainy or humid weather that causes dirty surfaces can significantly reduce their effectiveness. Moreover, these covers must be wiped cleaned with a cloth or washed with soap and water.
• These covers are for temporary use, since they are designed from light materials that cannot stay under electrical stress for extended periods. Thus, they must not remain installed for long without frequent checking based on standard specifications. Covers must be removed by end of the work day, if possible.