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Compressed gas cylinders used for a variety of purposes and may contain any number of industrial or research gases. The nearly ubiquitous presence and regular handling of compressed gas cylinders elevates the risk associated with these and drives general standards for storage, labeling, handling, use, and transportation of compressed gas cylinders.
Compressed gas cylinders present three basic hazards: the physical handling, movement & storage of the cylinder itself, the pressure of the cylinder, and the contents of the cylinder. This standard is developed to address the physical and pressure related hazards associated with compressed gas cylinders. For toxic or hazardous gases, see the The Compressed Gas Safety Program.
Compressed gas cylinders come in different shapes and designs, which are mostly based on the pressure of the gases they contain. In general, they are grouped as high-pressure cylinders or low-pressure cylinders.
The high pressure cylinders are typically tall and narrow, thick-walled, heavy when empty, generally made of steel or aluminum, and can withstand up to 10,000 psi. Common examples are nitrogen, helium, hydrogen, oxygen, and carbon dioxide cylinders.
Low-pressure cylinders are typically fatter and lighter than high pressure; they have thin-walled, welded seams, and can withstand up to 500 psi. Common examples are liquefied petroleum gases (LPG, like propane) and refrigerant gases.
Lecture bottles are smaller compressed gas cylinders that usually have an internal volume of 0.4 liters and can contain ~50 liters of a desired gas.
There are two types of lecture bottles: refillable and non- refillable. The refillable type of lecture bottles can be distinguished by their ability to use standard regulators that are used for full sized cylinders. The non-refillable lecture bottles can be distinguished by their use of smaller regulators
Confirm cylinder content.
Visually inspect them for damage and that a valve cap is in place and the valve is free from damage
Confirm that cylinder(s) is/are properly labeled.
Cylinders delivered without labeling or identification should not be accepted.
Do not rely on color as your primary method of identification.
Cylinder color changes for different suppliers, which makes it unreliable as a method of identification
Gas cylinders shall not be stored in exits or dedicated exit passageways, exit stairways or other dedicated exit routes.
Gas cylinders shall only be stored or used in approved locations.
Always store gas cylinders in well-ventilated areas.
Do not store gas cylinders in damp areas, near salt or corrosive chemicals, vapors, heat, or directly exposed to the weather.
The use of rope or cable-ties to secure cylinders is not permitted.
Always store gas cylinders in an upright condition and properly secured. They must be secured to a wall, table or lab bench using an appropriate chain or strap holder as purchased from a laboratory equipment supplier or custom made by the machine shop.
Secure gas cylinders with a chain or appropriate belt above the midpoint, but below the shoulder of the cylinder. Laboratory cylinders less than 45 cm (18 inches) tall may be secured by approved stands or wall brackets.
Cap cylinders when not in use.
Cylinders should be stored such that cylinders are used in the order in which they are received.
Do not store cylinders for longer than one year without use. Contact the chemical warehouse to return unused cylinders.
Compressed gas cylinders are not to be stored on hand trucks/carts.
Toxic or Hazardous Cylinders must be assessed with HSE and may require additional use/storage requirements. The Compressed Gas Safety Program
Lecture bottles should be stored in specific holders/racks (SAP Code number 3000007945).
Keep full cylinders separated from empty cylinders and properly labeled with a tag indicating: Full / In Use / Empty.
Keep cylinders away from locations where they might form part of an electrical circuit, such as next to electric power panels or electric wiring.
Keep cylinders clear of heat sources and of combustibles where they could be exposed to direct heat in emergency.
Segregate cylinders by hazard classes (oxidizers, flammables, toxics, etc). See the The Compressed Gas Safety Program or contact HSE for a risk assessment of gas storage and use.
Do not store flammable gases (e.g. acetylene) near oxidizers (e.g. oxygen) or combustible materials.
Store oxygen (full or empty) away from flammable gases. Oxygen should be stored at least 20 feet away from flammable gases or separated by a 5ft. high non-combustible wall having a fire-resistance rating of at
least one-half hour.
Never store liquid or gas chlorine cylinders with ammonia cylinders.
Always use a suitable cylinder cart for transporting cylinders, with the cylinder securely chained or strapped to the cart.
Do not roll or drag a cylinder to move it or allow cylinders to strike each other or any other surface violently.
To secure the cylinder to a cart, first move the cart within two feet of the cylinder and then slowly walk the cylinder to the cart.
A cart should be used to transport the cylinder short as well as long distances.
Protective valve caps must be secured when moving cylinders. Do not lift or move the cylinder by the cap.
The gas cylinder valve is the primary safety mechanism and is fitted with pressure relief valves of different types (depending on the cylinder) to protect against catastrophic failure of the cylinder valve.
Always protect the valve and ensure it is in excellent condition.
Do not tamper with cylinder valves.
Valves should never be opened without a regulator attached.
Never open the cylinder valves unless the regulator is completely closed. Likewise, always turn off the cylinder by first closing the main cylinder valve and then the regulator. The pressure gauges should go back to zero
Always open the main cylinder valve slowly and avoid opening it all the way.
Do not face the gauge while opening a cylinder. Stand on the side in case of a malfunctioning valve.
Cylinder valve must be closed when the cylinder is not in active use.
Never use wrenches or pliers to open cylinder main valve. If the valve does not rotate, contact the supplier immediately
The regulator is another important safety device, allowing for cylinder pressures to be brought to a usable working pressure. Regulators come as single stage for short term applications and two stages for long term applications. Regulators are constructed from brass or stainless steel.
The application will define the required regulator. If you are unsure of which kind of regulator to use, consult your gas supplier or HSE.
Regulators are designed to be fitted directly to the cylinder valve. No other fittings, connections or lubricants shall be used to connect a regulator to a gas cylinder valve.
Regulators for flammable gases are left hand threaded and have a notch cut out of faces on the securing nut to distinguish them from non- flammable gas regulators.
Piping is utilized to deliver the gas from the regulator to the required instrument, experiment or location. It is often one of the most overlooked components of a system. All piping and equipment must meet the standards of the Compressed Gas Association
Ensure the piping is compatible for the system pressure and for the specific gas. The Compressed Gas Saf
Never use use Tygon or plastic piping for any portion of a high- pressure system, or Ex: When piping hydrogen, use stainless steel tubing to prevent the buildup and potential spark from static electricity.
Keep piping connections tight
Periodically inspect piping connections for leaks and damages.
Ground all cylinders and piping containing flammable gases to static electricity hazards
All responsible users of compressed gas cylinders must be trained on proper use and handling techniques.
Cylinder installation should be evaluated before use to ensure its operations would not introduce additional hazards to the area.
Use a cylinder cap hook to loosen tight cylinder caps. SAP Code number: 3000012020 and 3000012019
Release pressure from systems before connections are tightened or loosened and before any repairs.
Inspect the system and ensure appropriate regulator, compatible manifold materials, and pressure-rated tubing and piping for all applications. Do not alter, adapt, or use Teflon tape on regulators
Check piping and connections for integrity
Wear the right PPE during use, particularly when installing and pressurizing the system
Lab coat and safety glasses are the minimum required.
Pressurize regulators slowly and ensure that valve outlets and regulators are pointed away from all personnel when cylinder valves are opened.
Leak test fittings using Snoop or soap solution. Never use an open flame to detect leaks.
Position cylinder valves are positioned in a way that is always accessible.
Cylinders which require a wrench to open the cylinder valve shall have the wrench left in place on the cylinder valve while it is open. Never apply excessive force when trying to open valves.
Return cylinders with corroded valves to the supplier. Do not try to open it.
When using more than one gas, be sure to install one-way flow valves (check valves) from each cylinder to prevent mixing, otherwise accidental mixing can cause contamination of a cylinder.
Close valves on gas cylinders when a system is not in use.
Shut-off valves must not be installed between pressure relief devices and the equipment they are to protect.
Use pressure relief valves in downstream lines to prevent high pressure buildup in the event that a regulator valve does not seat properly and a tank valve is left on.
Relief valves should be vented to prevent potential buildup of explosive or toxic gases.
Valves should only be opened to the point where gas can flow into the system at the necessary pressure. This will allow for quicker shutoff in the event of a failure or emergency.
Never use adapters or exchange fittings between tanks and regulators.
After an experiment is completed, turn the cylinder valve off first, and then allow gas to bleed from the regulator. When both gauges read “zero”, remove the regulator and replace the protective cap on the cylinder head.
After an experiment is completed, turn the cylinder valve off first, and then allow gas to bleed from the regulator. When both gauges read “zero”, remove the regulator and replace the protective cap on the cylinder head.
Leaks from gas cylinders require immediate attention. How to handle the problem will depend on the kind of gas, the size of the leak, the area where the cylinder is located, and other factors. KAUST Fire Department will respond to major leaks and release of toxic and flammable gases.
For questions and troubleshooting contact: 959
Verify suspected leaks using a portable gas detector or soapy water solution (a flame should not be used for detection). If the leak cannot be stopped by tightening a valve gland or packing nut, emergency action procedures should be initiated by calling 911 from a campus phone
In the event of a large gas release activate the following Emergency Procedures:
