EPA 608 Technician Certification Safety, Cylinders, and Shipping Summary

Refillable recovery cylinders are painted with a gray body and a yellow top so they are easy to tell apart from new-refrigerant cylinders. They must be DOT-approved.

Wrong choices

• Solid red: Solid red is not the recovery cylinder color code.
• Light blue body with a black top: Light blue is used for some new refrigerant cylinders, not recovery cylinders.
• Green body with a white top: Green and white is not the recovery cylinder color code.

Liquid refrigerant expands when it warms. If a cylinder is too full, the liquid can fill it completely and the pressure can rise enough to burst it. Do not fill a recovery cylinder more than 80 percent full of liquid; use a scale or float switch to check.

Wrong choices

• 95 percent of its capacity: 95 percent is dangerously full.
• 60 percent of its capacity: 60 percent is safe but is not the usual limit.
• 90 percent of its capacity: 90 percent leaves too little room for the liquid to expand.

Use dry nitrogen to pressurize for leak testing. Never use oxygen or compressed air: oxygen and oil under pressure can explode, and air adds moisture.

Wrong choices

• Acetylene: Acetylene is a flammable fuel gas.
• Compressed air: Compressed air brings in moisture and can create an explosive mix with oil and refrigerant.
• Oxygen: Oxygen can explode when it contacts oil under pressure.

Disposable cylinders are made for one use and must never be refilled. Any refrigerant left in them must be recovered, not vented.

Wrong choices

• Refill it with recovered refrigerant: Disposable cylinders must never be refilled.
• Fill it with nitrogen for leak testing: Disposable cylinders should not be reused for nitrogen or anything else.
• Use it as a recovery cylinder for small jobs: Disposable cylinders are not recovery cylinders.

Liquid refrigerant boils at very low temperatures, so it can freeze skin and eyes and cause frostbite. Wear gloves and safety glasses or goggles when working with refrigerant.

Wrong choices

• Hearing damage: A spray does not damage hearing.
• Chemical burn from acid: Acids form only when refrigerant is heated and breaks down, not from a liquid spray.
• Electrical burn: Refrigerant does not cause electrical burns.

A full nitrogen cylinder holds very high pressure. Always use a pressure regulator to set a safe test pressure and a relief valve to protect the system from overpressure.

Wrong choices

• Only a quick-connect fitting: A fitting alone cannot control the high cylinder pressure.
• A heat gun to warm the nitrogen cylinder: Heating a nitrogen cylinder is dangerous and raises pressure.
• A charging scale: A scale does not control pressure.

Most refrigerant vapors are heavier than air. In a closed or low space they can displace oxygen and cause dizziness, unconsciousness, or death by suffocation. Ventilate the area, and use a self-contained breathing apparatus (SCBA) for a large leak.

Wrong choices

• All refrigerants catch fire at room temperature: Most common refrigerants are not flammable at room temperature.
• Refrigerant vapor turns into carbon monoxide: Refrigerant does not turn into carbon monoxide.
• Refrigerant vapor is lighter than air and collects at the ceiling: Most refrigerant vapors are heavier than air and collect low.

Before shipping, a refrigerant cylinder must be labeled with the type of refrigerant and the Department of Transportation (DOT) hazard classification. Follow DOT and your reclaimer's instructions.

Wrong choices

• Only the technician's certification number: The certification number alone does not meet shipping rules.
• Only the date of recovery: The date alone does not meet shipping rules.
• No labels are needed if the cylinder is gray and yellow: Cylinder colors do not replace the required labels.

EPA lists SCBA as protective equipment for extreme cases, such as a large leak in an enclosed area where refrigerant may have pushed out the oxygen. Gloves and goggles are the everyday protection.

Wrong choices

• During every routine gauge check: Routine gauge checks do not require SCBA.
• Whenever recovering from a window air conditioner outdoors: Small outdoor jobs do not normally require SCBA.
• Only when working with nitrogen: SCBA is for oxygen-deprived air, which is mainly a concern with large refrigerant leaks.

Heating a cylinder raises the pressure inside, and a flame can weaken the metal. The cylinder can rupture violently. Never heat a cylinder with an open flame.

Wrong choices

• Heat lowers the pressure and causes a vacuum: Heating raises pressure; it does not create a vacuum.
• Heat makes the refrigerant turn into nitrogen: Refrigerant does not turn into nitrogen.
• It is safe if the valve is closed: A closed valve makes it more dangerous, because pressure has nowhere to go.