Plan carefully when setting up an experiment which involves gaseous materials and gas cylinders.

	NFPA sets limitations on the number of cylinders that should not be exceeded in a laboratory. Do not acquire more than: three 10" x 50" flammable gas or oxygen cylinders and three 4" x 15" cylinders of toxic gases (such as arsine, chlorine, fluorine, hydrogen cyanide, nitric oxide)
	Make sure you have adequate ventilation to bring in and work with toxic gases. These materials will require constant local ventilation to ensure the safety of the personnel. Adding ventilation is not usually a straight forward task - it usually takes considerable money and time to have installed, so plan accordingly.

Be familiar with the guidelines on safe transport of high pressure cylinders:

	when the cylinder is not in use the valve protection cap must be in place to protect the valve;
	never drag, slide or roll the cylinder - get a cylinder cart or truck and use it;
	always have the protective cap covering the valve - never transport with the regulator in place; and
	make sure the cylinder is secured to the cart during transport.

Special precautions are also required when storing cylinders:

	cylinders must be secured at all times to a fixed location - a wall, the labbench, etc.;
	they must be secured at a point approximately 2/3 of its height, using appropriate material - chain, plastic coated wire cable, commercially available cylinder straps, etc.;
	as with any hazardous material, you may not store gas cylinders in public hallways or other unprotected areas;
	cylinders must be secured individually, i.e., one restraint per cylinder; and
	cylinders should be segregated in hazard classes while in storage, at the minimum, oxidizers (such as oxygen) must be separated from flammable gases, and empty cylinders should be isolated from filled cylinders.

Before the cylinder is first used the following precautions should be taken:

	make sure the cylinder is equipped with the correct regulator. Always use the regulator designed for the material in use, and be especially careful that under no circumstances is grease or oil used on regulator or cylinder valves because these substances may cause an adverse, dangerous reaction within the cylinder.
	the cylinder should be placed so that the valve handle at the top is easily accessible at all times.
	open the valve slowly and only with the proper regulator in place - the valve should be opened all the way. Never leave a valve part way open - either open it all the way or close it all the way.
	the valve should never be left open when equipment is not in use, even when empty; air and moisture may diffuse through an open valve, causing contamination and corrosion within the cylinder.
	if using a toxic or irritating gas, the valve should be opened only while the cylinder is in a working fume hood and even so, it would also be prudent to direct the valve and potential gas flow away from lab personnel.

When cylinders are in use consider the following:

	never rely on the color coding to identify the gas! Different manufacturers may use different coding systems.
	never refill a cylinder - mixing of residual gases in a confined area may result in a serious and devastating reaction.
	don't use oxygen in place of compressed air.
	don't use copper fittings or tubing on acetylene tanks - explosion may result.

Leaking cylinders constitute a threat that may be so serious that entire facilities may be called on to evacuate and outside help may be required to assist. 

Call the instructor, Lee Clark, or Safety immediately!

After the cylinder is no longer needed, the following steps should be taken:

	never completely empty the cylinder; always leave a residual gas pressure of 30psi.
	do not keep hazardous materials in the lab beyond the time they are needed. Cylinders have a finite life expectancy. This is especially true for cylinders containing corrosive materials. If you are not using it - get rid of it!
	if the cylinder is empty, replace the cap and remove it to the storage area for empty cylinders. Mark it "MT" or label in some other fashion that will allow everyone to know its status.

*** Remember - the greatest physical hazard represented by the compressed gas cylinder in the laboratory is the tremendous force that may be released if it is knocked over! ***