Taking safety measures when working with HVAC refrigerant can help avoid hazardous circumstances and injuries. If not dealt with promptly, some HVAC systems issues can trigger an explosion. Though an old furnace isn’t exactly a ticking time bomb, it isn’t a toaster also.
Additionally, obvious hazards such as electrical wiring, sharp metal, and climbing ladders, the technician or homeowners who are DIY novices that intend to clean or repair their HVAC system need to be aware of the safety risks that refrigerants pose.
If the refrigerant remains confined in the cylinder, then it presents little danger to people. The risk occurs when the refrigerant comes out of the container, often fast and suddenly. Thus, regular maintenance and safety checks should be regularly implemented to avoid potential health risks and damages.
Consistent inspections on containers and systems for holding pressure, and preparing safety procedures and equipment to lessen personal exposure after sudden releases should help prevent any damage or injuries when handling refrigerants.
Refrigerant hazards from fall into three categories:
Combustible refrigerants present an immediate peril when released into the air. The refrigerant can mix with air at atmospheric pressure and ignite, producing a flame and perchance an explosion to happen. The utilization of flammable refrigerants is limited to controlled environments that have the explosion-proof equipment, monitors, proper ventilation, and mostly few people near the system because of the apparent hazards.
- Toxicity and personal exposure
Before being released for air conditioning use, most refrigerants go through extensive toxicity testing. Testing includes a range of exposure levels and times to define any likely effects on test animals.
Brief exposures at high concentrations show any acute health risks such as irritation, sensitization of the heart or adrenaline and lethal concentration. Likewise, experiments that expose animals for extended periods of time, such as three months to two years, are intended to show chronic problems. These can include changes to cells or mutagenicity, effects on organs or carcinogenicity, and reproductive problems.
1,000 ppm is the maximum value for any chemical, though many refrigerants have presented no negative results in toxicity tests in much greater volume than that. Other chemical producers have related exposure level indexes based on the similar criteria. These are the WEEL or Workplace Environmental Exposure Limit set by the AIHA or American Industrial Hygiene Association; PEL or Permissible Exposure Limit established by OSHA; as well as AEL or Acceptable Exposure Limit utilized by DuPont.
To the HVAC technician, what all of this data means, however, is that refrigerants, in general, are safe enough to use provided you don’t inhale too much of them.
- Physical hazards
One of the most obvious risks of refrigerant is the fact that it’s a liquefied gas under pressure. Unexpected, sudden release of pressurized refrigerant can result in personal injury.
Moreover, liquid refrigerant will flash and boil to vapor when suddenly released from high pressure to atmospheric pressure. As you would expect, the temperature of the refrigerant will descend rapidly to the boiling point and the refrigerant will absorb heat fast and can cause frostbite if it touches your skin.
The best way to avoid pressure-related risks is always to use cylinders and system components that have the defined pressure rating for the refrigerant you’re using. Pressure ratings for system components must be selected based on the expected service loads for the intended purpose. Constantly check for signs of excessive wear or damage before filling recovery cylinders, buying new refrigerant cylinders or installing new parts to a system.