06 Jul Portable Light Strings – Electrical Safety

Portable Light Strings – Electrical Safety

Portable light strings are commonly used to provide temporary illumination in construction, maintenance, confined spaces, and other work areas. Because these lights may be exposed to moisture, physical damage, combustible materials, and hazardous atmospheres, improper use can result in electrical shock, electrocution, burns, fires, or explosions.

Inspect Before Use

Inspect portable light strings before installation and before they are energized.

• Check cords for cuts, cracks, fraying, exposed conductors, or damaged insulation.
• Inspect plugs and connectors for damage.
• Make sure required grounding prongs are present and intact.
• Inspect fixtures, lamp holders, globes, and guards for cracks or damage.
• Verify that all connections are secure.
• Make sure lamps are intact and properly installed.
• Remove damaged or defective equipment from service immediately.

Never make makeshift repairs to damaged electrical cords, plugs, or fixtures.

Grounding and GFCI Protection

Portable light strings must be properly grounded unless specifically designed and approved as double-insulated equipment.

• Never remove or defeat a grounding prong.
• Plug equipment only into properly grounded electrical systems.
• Use ground-fault circuit interrupter (GFCI) protection where required.
• On construction sites, OSHA requires employees using temporary wiring and receptacle outlets to be protected by GFCIs or an applicable assured equipment grounding conductor program.
• Keep plugs, connections, and electrical components away from standing water.
• Never handle energized electrical equipment with wet hands.

Wet or conductive locations increase the potential for electrical shock and require additional precautions.

Protect Lamps and Fixtures

Portable lamps must be protected from accidental contact and breakage where required.

• Keep required guards in place.
• Never use a fixture with exposed energized components.
• Do not operate a light with a broken lamp, damaged globe, or defective fixture.
• Position lights where they will not be struck by workers, tools, equipment, or materials.
• Disconnect the light string from its power source before replacing lamps or performing repairs.
• Allow hot lamps to cool before handling.
• Wear appropriate gloves when handling broken glass.

Never attempt to remove a broken lamp from an energized fixture.

Fire and Burn Prevention

Portable lamps can generate enough heat to burn employees or ignite nearby combustible materials.

• Keep lights away from wood, paper, plastic sheeting, insulation, clothing, flammable materials, and other combustibles.
• Do not allow hot lamps to contact combustible surfaces.
• Never cover lamps or fixtures with materials that can trap heat.
• Position lights where employees cannot accidentally contact hot surfaces.
• Do not hang a light by its electrical cord unless it is specifically designed for that purpose.

Wet and Damp Locations

Only equipment suitable for the environment should be used in wet or damp locations.

• Use required GFCI protection.
• Keep electrical connections dry and protected.
• Do not allow plugs or connections to lie in standing water.
• Protect cords from water, sharp edges, crushing, and other damage.
• Inspect lighting frequently when environmental conditions could damage the equipment.

If a light string becomes wet or damaged, disconnect it when safe to do so and remove it from service until it has been properly evaluated.

Confined and Enclosed Spaces

Confined spaces may contain electrical hazards as well as oxygen-deficient, toxic, or flammable atmospheres.

Before introducing portable lighting into a confined space:

• Follow the company’s confined-space entry procedures.
• Determine whether atmospheric testing is required.
• Evaluate the potential for flammable gases or vapors.
• Use electrical equipment approved for the conditions and applicable hazardous-location classification.
• Protect cords and fixtures from physical damage.
• Maintain required ventilation and atmospheric monitoring.

Portable lighting does not make a hazardous atmosphere safe.

Flammable or Explosive Atmospheres

Ordinary portable light strings can provide an ignition source and must not be used where flammable gases, vapors, or combustible dust may create a hazardous atmosphere.

Where a classified hazardous location exists:

• Use lighting specifically approved for the applicable hazardous location.
• Inspect cords, plugs, fixtures, globes, guards, seals, and gaskets before use.
• Make sure fittings and enclosures are properly assembled and secured.
• Never substitute ordinary temporary lighting for equipment required by the hazardous-location classification.

The older term “explosion-proof” does not automatically mean that a light is suitable for every hazardous atmosphere. Equipment must be properly approved and identified for the particular location and hazard.

If the atmosphere has not been evaluated or there is uncertainty about the suitability of the lighting equipment, do not energize the lights until the conditions have been evaluated by a qualified person.

Cord Placement

Install portable light strings so they do not create additional hazards.

• Keep cords out of walkways whenever practical.
• Protect cords from vehicle and equipment traffic.
• Keep cords away from sharp edges and hot surfaces.
• Do not attach cords with staples, nails, or other methods that could damage the insulation.
• Do not create slip or trip hazards.
• Keep lights and cords clear of moving machinery.
• Do not overload electrical circuits.

Remember

Portable light strings are temporary electrical equipment and must receive the same attention as other electrical tools and equipment.

Inspect before use, maintain required grounding and GFCI protection, keep lamps guarded, protect cords from damage and moisture, and never use ordinary lighting in a hazardous atmosphere.