Heating, ventilation and air conditioning (HVAC) systems are found in nearly all buildings. These systems can pose some significant electrical hazards for workers and the general public. According to one estimate, more than 40,000 injuries and nearly a dozen fatalities are caused by HVAC systems every year. Many of these incidents can be prevented by following some basic safety protocols and exercising hazard awareness.

Although there are no specific Occupational Safety and Health Administration regulations addressing electrical work in HVAC systems, other general standards cover these hazards. Risks associated with HVAC systems and their electrical components include improper wiring, overloaded circuits, improper grounding and lack of maintenance. These hazards can result in electric shocks and fires and cause serious injury or even death.

Wiring

HVAC systems rely on a complex network of electrical circuits and components. Faulty or insufficient wiring can be the root cause of electrical fires and injuries. Therefore, proper wiring practices are of the utmost importance in HVAC work. All electrical wires and connections should be properly insulated to prevent accidental electrical contact. Safe installation should also include use of correctly sized wiring, secure grounding practices and adherence to local electrical codes/regulations and NFPA 70E, Standard for Electrical Safety in the Workplace.

Grounding

Improper grounding can cause electrical shocks and damage HVAC equipment. Grounding the system properly will ensure that excess electrical current safely dissipates into the ground and reduce the risk of electrical accidents.

Circuit overload

Overloading circuits is also a common mistake when wiring appliances or electrical equipment. Overloads can cause overheating and result in electrical fires. Workers must calculate the electrical load accurately and distribute it evenly across circuits to prevent overloads when working with any appliance or electrical equipment. To help avoid overloads and ground faults, circuit breakers and ground fault circuit interrupters should be installed on all systems. These devices automatically trip when detecting abnormal electrical activity, which prevents damage and offers protection against potential accidents.

Maintenance

HVAC systems must be properly and regularly maintained. Neglected maintenance, such as failing to inspect and replace worn-out components, can increase the likelihood of a hazardous situation occurring. As a result, regular inspections and timely repairs are critical in identifying potential risks and preventing future incidents.

Before conducting maintenance or repair work on an HVAC system, workers must ensure it is completely disconnected from the power source and that all the appropriate lockout/tagout protocols are followed. Inspections should focus on electrical components, motors, capacitors and wiring. Corrosion, fraying or disconnection of electrical components are among the most common issues. Any damaged or worn-out parts should be replaced immediately to prevent potential hazardous scenarios. HVAC systems should also be cleaned routinely in accordance with manufacturer recommendations.

These systems should only be installed, repaired and maintained by a properly trained professional technician or electrician to ensure worker and end-user safety, as well as proper equipment functionality. It is imperative to make sure all employees responsible for this work undergo the appropriate training and certification to handle electrical components safely. Workers should also stay in tune with the latest safety protocols and industry practices.

Nonelectrical hazards

Nonelectrical hazards to be aware of when working with HVAC systems include work on rooftops and in confined spaces and handling refrigerants. Proper fall protection should always be used when working from heights. Falls are the deadliest occupational hazard.

Refrigerants are dangerous because they can replace the oxygen in the lungs and are difficult to expel once inhaled. They are heavier than air and can cause unconsciousness and even death. There are OSHA regulations, including HazCom, that address how to safely use, store and respond to an exposure of these dangerous chemicals. Similarly, there are standards in place addressing work in confined and enclosed spaces.

HVAC system users should familiarize themselves on basic functionality and be able to identify warning signs of an electrical issue. Indicators that something isn’t right include frequent tripping of an electrical breaker, trouble turning the unit on or off, bad capacitors or compressor issues. If any of these occur, have an HVAC or electrical professional evaluate the problem.

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