Putting the wrong refrigerant into a system can cause a violent explosion. When a cylinder has been emptied, close the cylinder valve immediately to prevent the entrance of air, moisture, or dirt. Also, be sure to replace the valve protection cap. Do NOT use cylinders as rollers and supports. Do NOT tamper with the safety devices in the valves or cylinders.
Open cylinder valves slowly.
Be sure the threads on regulators or other connections are the same as those on the cylinder valve outlets. If the cylinders are exposed to excessive heat, a dangerous increase in pressure will occur. If cylinders must be stored in the open, make sure they are protected against extremes of weather. As a freezing agent, R-12 is so powerful that even a very small amount can freeze the delicate tissues of the eye, causing permanent damage. It is essential that goggles be worn by all personnel who may be exposed to a refrigerant, particularly in its liquid form.