Tag Archives: Electrical Safety

Electrocution Hazards: What Could Go Wrong?

An electrical hazard is a serious workplace hazard that exposes workers to Burns (B), Electrocution (E), Shock (S), Arc flash (A), Fire (F), Explosion (E), etc. Therefore, BE-SAFE is the motto for recognizing, avoiding and protecting against all of these electrical hazards in construction sites.

All electrical hazards may not prove to be fatal however, electrocution results when a person is exposed to a lethal amount of electrical energy.

With the wide use of power tools on construction sites, flexible extension cords are necessary. Since they are often flexible, unsecured and exposed, they are also more susceptible to damage than the fixed wirings. Hazards are created when cords, cord connectors, receptacles, and other connected equipment are improperly used and maintained.

It is not uncommon to find incidents in construction sites where workers came in contact with energized sources resulting in electrical shock and burns.

The severity of an electrical shock depends on a number of factors such as the amount of current, the length of time of the exposure, the pathway through the body, and whether the skin is wet or dry. Electrical burns are among the most serious burns which require immediate medical attention.  

Overhead and buried power lines are especially hazardous because they carry extremely high voltage ranging from 120 to 750,000 volts. Workers in the water, sewer, pipeline, road, communication, power line construction and power distribution industries are highly prone to overhead power line (OHPL) injuries or fatalities.

Too often a desire for work convenience, demand for rush job and a failure to identify immediate OHPL hazard may combine to cause tragic accidents.

Electricity can be quite unforgiving when proper procedures are not followed, therefore, it is essential that workers are informed, trained and reminded of safe practices/procedures around power lines. Maintaining safe distance from the overhead power lines is the best option. Make sure that the equipment and activity (such as cranes and other high reaching equipment) are located within a safe working distance from power lines.

For up to 200kV power lines, the minimum Line Clearance Distance is 15 feet which increases further as the voltage increases. Moreover, the Working Clearance Distance must be further away from the Line Clearance Distance.

It is important to remember that the contact with the OHPL is not necessary to cause injury or death, as arcing can still occur when minimum clearances are not observed. During arcing, workers or equipment can become energized without touching the OHPL directly. If they are working inside the minimum Line Clearance Distance, electricity can arc, or jump across the gap.

Besides, the construction workers must be trained to understand the severe consequences associated with the OHPL hazards, to avoid harm from OHPL and to respond in the event of an incident related to OHPL.

Ground Fault Circuit Interrupter (GFCI) is designed to protect people from severe and sometimes fatal electrical shocks. GFCI detects ground faults and interrupts the flow of electric current by limiting the duration of an electrical shock. Unlike multiple GFCI outlets, one GFCI Circuit Breaker can control and protect an entire circuit. It can also be installed as a replacement for a regular circuit breaker on the main circuit board.

To avoid electric shocks workers need to routinely inspect extension cords and other portable tools for any cuts or abrasion. When the insulation of extension cord is damaged, exposed metal parts in the surrounding may become energized if a live wire inside touches them. Electric hand tools that are old, damaged, or misused may also have damaged insulation inside.

Workers need to know that even when the power system is properly grounded, electrical equipment can instantly change from safe to hazardous because of extreme environmental conditions and rough treatment.

Following lockout/tagout procedure is an essential safety measure to protect workers from being electrocuted while working on or near electrical circuits and equipment. Moreover, the lockout/tagout can also prevent the accidental release of hazardous energy such as gases, fluids, or solid matter during equipment maintenance or repair jobs.     

Failing to Verify Energy Isolation and Zero Energy

Verification of Energy Isolation and Zero Energy is a must to avert such Arc Flash incidents. Before work begins: (1.) Identify all energy sources. (2.) Confirm that hazardous energy sources have been isolated, locked and tagged. (3.) Check for zero energy. (4.) Test for residual or stored energy.