When discharging gases into a liquid, a trap should be used to prevent back-flow of liquids into the regulator or cylinder. Proper respiratory equipment shall be readily available for use during an emergency. The proper regulator should be connected. Be careful not to cross thread or over tighten the connections. Never stand in front of or behind the pressure gauge as the main tank valve is opened.
Pressure gauges can explode.
When opening the valve on a cylinder containing a corrosive or toxic gas, stand on the side opposite the valve opening. Safety glasses should be worn when dispensing compressed gases to prevent eye damage from equipment failure. Always use the appropriate regulator. Regulators for non-corrosive gases are usually made of brass. Corrosion resistant regulators should be used with gases such as ammonia, boron trifluoride, chlorine, hydrogen chloride, hydrogen sulfide, and sulfur dioxide.