Electrical Safety Toolbox Talk

Electrical Safety Talk

When working on a construction site, you must stay aware of many different safety risks. One of the biggest hazards to construction workers and electrical contractors in particular is electricity.

Understanding the dangers of electricity and knowing how to avoid them is the first step of electrical safety.

How dangerous is electricity?

Unfortunately, many people are completely unaware of the risks electricity poses until it’s too late.

According to Electrical Safety Foundation International, between 1992 and 2010 there were 5,096 fatalities in the United States due to contact with electricity. There were a total of 66,748 injuries that required days away from work in the same time period due to electricity. The majority of these electrical injuries and fatalities were in the construction industry.

These statistics do not include injuries caused by secondary events. A secondary event is an injury indirectly caused by electricity—for example, an individual falling from a ladder due to getting shocked. If these types of injuries were included, the numbers would be even higher.

Also, every day there are workers who suffer some type of shock but do not seek or require treatment for their injuries. Because of this, it is difficult to fully track the total impact of electrical shock in the workplace.

Common electrical hazards

In order to properly protect yourself and everyone else on the jobsite, you will need to be sure everyone is aware of common electrical hazards. The first step to avoiding accidents and injuries is knowing the potential dangers.

Here are some of the different types of electrical hazards:

Improper grounding

Grounding is the process used to eliminate unwanted voltage. A ground is a physical connection to the earth. This allows leakage voltage to dissipate to the ground instead of going through you and possibly causing an injury.

When a power tool is not grounded properly, a hazard exists because unwanted voltage cannot be safely eliminated. The metal parts of an electrical wiring system that we touch (switch plates, ceiling light fixtures, conduit, etc.) should be grounded and at 0 volts. If the system is not grounded properly, these parts may become energized.

If you contact a defective electrical device that is not grounded (or grounded improperly), the electrical current will take the path of least resistance which will be you, and you will experience an electric shock.

Exposed electrical parts

When covers of electrical panels or equipment are broken, incomplete, or missing this creates a serious hazard. Some exposed electrical parts hazards to look out for are:

• Wires or other electrical parts that are exposed

• Cover removed from a wiring or breaker box

• Missing breaker from a panel box exposing the wires or terminals

• Overhead wires coming into the job site that may be exposed

• Exposed electrical terminals in motors, appliances, and electric equipment

• Older equipment that may have exposed electrical parts

Temporary lighting has to be installed with safety in mind. Light fixtures should be properly grounded, with a cage around the bulb, and wires should be dressed properly.

You must always keep safety in mind when working near electricity.

Inadequate wiring

An electrical hazard exists when the gauge of a wire is too small for the current it will carry.

Normally, the circuit breaker is matched to the wire size. When the gauge of a wire is too small for the current it is supposed to carry, the wire will heat up, and the heated wire could cause an electrical fire.

Make sure to use properly rated extension cords when working with power tools. When you use an extension cord, make sure the gauge of the wire you are placing into the circuit is not too small for the equipment. Even if the circuit breaker is the right size, if the gauge of the wire is too small, you are creating an electrical hazard.

A tool plugged into the extension cord may use more current than the cord can handle without tripping the circuit breaker. This could damage the tool in addition to causing a fire. Always make sure that any extension cord you are going to use is properly rated for the equipment you are going to plug into it.

Damaged insulation

Insulation that is defective or inadequate is an electrical hazard. Usually, insulation is made of plastic or rubber covering over the wires. Insulation prevents conductors from coming in contact with each other or people. Insulation also protects the wires from getting damaged due to the environment.

When insulation is damaged, exposed metal parts may become energized if a live wire touches them. Extension cords may have damaged insulation or the insulation inside an electrical tool may be damaged. Electric hand tools that are old, damaged, or misused may have damaged insulation inside. If you touch these power tools or other damaged equipment, you will receive a shock. You are more likely to receive a shock if the tool is not grounded or not double-insulated. Double-insulated tools have two insulation barriers and no exposed metal parts.

Overloaded circuits

Overloads in an electrical system are hazardous because they can produce heat, arcing, or even a fire. Wires and other components in an electrical system have a maximum amount of electrical current they can carry safely. If too many devices are plugged into a circuit, the electrical current will heat the wires to a very high temperature. Also, if any one tool uses too much current, the wires will heat up.

In order to prevent too much electrical current in a circuit, a circuit breaker or fuse is placed in the circuit. If there is too much current in the circuit, the breaker “trips” and opens like a switch. If an overloaded circuit is equipped with a fuse, an internal part of the fuse melts, opening the circuit.

Both breakers and fuses do the same thing—open the circuit to shut off the electrical current. If the breakers or fuses are too big for the wires they are supposed to protect, an overload in the circuit will not be detected and the current will not be shut off. Overloading leads to overheating of circuit components (including wires) and may cause a fire.