Gas cylinder safety precautions: The scope of this article is as general guidelines for gas cylinder, and safe cylinder handling and does not intend to cover or describe all types of gases. Industry in general requires the use of compressed gases for a wide range of operations. We must periodically deliver gas cylinder safety toolbox talk.
Handling and storage of compressed gases present a particular hazard. Depending on the gas, there is a potential for simultaneous exposure to mechanical and chemical hazards. Gases can be flammable or combustible, explosive, corrosive, poisonous, inert, or a multifactorial combination of hazards.
Hazards associated with compressed gases include oxygen displacement, explosion hazards, the toxic effect of some gases, and the physical hazards of a punctured cylinder. There are over 200 different types of gases that are stored and transported in cylinders. Let's muniriyathse (safety zone) explain.
Compressed gases are typically divided into six basic categories, and some gases fall into more than one classification. The categories are:
- Flammable gases,
- Oxygen and oxidizing gases,
- Acid and alkaline gases,
- Acid and alkaline gases,
- Liquefied cryogenic gases and
- Inert gases,
Compressed gas cylinder safety precautions
There must be visible signs in the areas designated for the storage of flammable compressed gases or gases of any other type, the identification of the substances and the appropriate precautions (for example “Acetylene”, “Flammable gas”, “No smoking”, “Avoid open flames or any source of ignition”).
Any compressed gas cylinder must be secured in an upright position at all times to prevent it from falling. Cylinders may be individually connected to the wall, placed in a restraining cage, on metal structures provided with restraints, attached to wheeled carts, or other secure alternatives.
Chains or approved resistant straps can be used to secure cylinders at 2/3 of their height, but wires, cables, rags, hoses, shoelaces, clothesline loops, etc., are prohibited.
To protect the cylinder’s valve during storage or transport, the cap must be screwed on to protect the valve by hand force and remain so until the cylinder is in place and ready for use. When a cylinder requires removal from the area of operation when it is empty, its cap must be placed, clearly marked as “empty” and sent to the corresponding storage area. Full and empty cylinder storage areas should be in separate areas.
Never roll, drag or carry a cylinder, always use a properly designed wheeled cart to ensure stability. Also, do not use cylinders as rollers to move loads.
Each company must have compiled the information related to the safety data sheets (MSDS) of each gas stored or used inside the facilities in a convenient place to facilitate consultation regarding safety topics such as storage, handling, transportation, personal protective equipment, incident and emergency response.
Training and coaching of personnel as in any other safety topic is key and should be maintained as a permanent program for new and existing personnel with refresher courses and exams.
Safety tips for gas cylinders
Make sure that compressed gases are only used for their intended purpose and by defined procedures and rules. Maintain appropriate records related to the handling and use of compressed gases, including an up-to-date inventory, personnel education and training records, and reported incidents. If handled properly, compressed gas cylinders are safe.
- Make sure storage areas for cylinders are dry, cool, and well-ventilated.
- Store cylinders in areas away from incompatible substances, excessive heat, moisture, salt, and other corrosive chemicals.
- Make sure the cylinders do not block the exit paths.
- Slowly open the valves using a T-handle wrench or the valve wheel.
- Never use oxygen to blow dust or other debris out of your work clothes.
- Check all relief fittings and connections for signs of tampering.
What type of hazard is a gas cylinder?
Oxygen, acetylene, argon, air, liquefied petroleum gas (LPG), nitrogen, and other gases are contained in various sizes and colours of metal cylinders. Gases are stored, transported, and handled in heavy metal cylinders at high pressure (for example, 2,400 psi —pounds-force per square inch— of internal pressure).
Imagine a sudden release of these gases caused by the valve breaking, the result turning the cylinder into a potential missile or fragmentation bomb, destroying everything in its path. Pressure and gas-specific risks are the main risks when it comes to compressed gases.
If the gas is flammable, flash points below room temperature aggravated by high diffusion rates present a fire or explosion hazard. Additional gas reactivity and toxicity hazards, as well as asphyxiation, can be caused by high concentrations of even “harmless” type gases, such as nitrogen or argon.
The contents of any compressed gas cylinder must be identified by a label or other legible means. As a procedure, the label should always be reviewed and “read”. A cylinder that lacks a label or is illegible must never be used, the supplier must reject it.
Gas Behavior
- As the temperature increases, the occupied volume increases (at constant pressure)
- As the temperature increases, if the volume remains fixed, the pressure increases.
What are the 4 hazards and dangers associated with compressed gas cylinders?
- Suffocation: The oxygen in the air can be displaced by other gases such as argon, nitrogen, and carbon dioxide.
- Cryogenic burns, heat burns,
- Fire and explosion,
- Toxic,
Gas cylinder safety rules
Metal cylinders containing compressed gases are essentially shipping containers and should not be subjected to mishandling, abuse or damage. This improper use can seriously weaken a cylinder and make it unsuitable for later use or transform it into a projectile with enough thrust to go through masonry walls, and ceilings, damaging construction, equipment, machinery, and personnel and even harming third parties.
What we have seen in the industry, for example, has been:
- Personnel carrying cylinders on shoulders (with or without caps), horizontal displacement of cylinders (rolling them),
- Storage or transport in a horizontal position in solid stacking,
- Rusted or beaten cylinders,
- Cylinders without chain securing and a cap,
- Manual transport of two cylinders at the same time by one person turning them on their axis,
- Storage in an open area exposed to sunlight, etc.
- Do staff and workers understand the inherent risks of compressed gas cylinders used in the plant or workplace?
- Is there training for the inspection, transport, handling storage and use of cylinders with compressed gases?
- Are there procedures and safety measures for the storage of compressed gases?
REFERENCES
– NFPA 55 Compressed Gases and Cryogenic Fluids Code.
– OSHA 29 CFR 1910.101 Compressed Gases (General Requirements).
How do you check a gas cylinder is safe?
- Only qualified and trained personnel can receive, store, handle and use cylinders with compressed or liquefied gases.
- Cylinders are thoroughly inspected for damage such as cuts, nicks, burn marks and/or obvious dents, valves are not bent or damaged. The surface of the cylinders is clean.
- Any cylinder noted with no labels, missing or illegible markings, and visible damage is not received and is rejected and reported to the supplier for replacement.
- The storage of cylinders with compressed gases is strictly in a vertical position and secured with chains or approved clamps at 2/3 of their height without exception to the wall, rack, or poles, at all times. Deviations are not allowed.
- Full and/or empty cylinder storage areas are well-ventilated, protected from environmental factors such as sunlight, and storm drains to prevent moisture corrosion, and protect cylinder bases from direct contact with the ground.
- The storage of oxygen cylinders is separated from cylinders containing flammable gases such as methane, LP gas, and hydrogen in 6.1 m. according to Chapter 7 of NFPA 55 or bounded by wall vs. fire height of 1.5 meters and minimum fire resistance of 0.5 h.
- Storage of cylinders at temperatures below 0°C is avoided; some mixtures separate under these conditions. Likewise, storage above 52°C is avoided to prevent the internal pressure of the cylinders from rising to a dangerous level.
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Conclusion
Gas cylinders, while incredibly useful for various purposes, demand the utmost respect and caution due to the pressurized gases they contain. Mishandling can lead to disastrous consequences, making safety precautions paramount. Here's a concise conclusion emphasizing key practices:
- Assume every cylinder is full, even if the gauge indicates otherwise.
- Wear appropriate personal protective equipment (PPE) like goggles, gloves, and appropriate clothing based on the gas type.
- Never tamper with safety devices or pressure relief valves.
- Always use a cylinder cart or trolley; avoid dragging, rolling, or lifting.
- Secure cylinders upright with chains or straps to prevent tipping or falling.
- Use the protective cap whenever the cylinder is not in use.
- Choose a cool, dry, well-ventilated area away from heat sources and ignition points.
- Do not store cylinders in direct sunlight or near corrosive materials.
- Maintain a safe distance from flammable materials and electrical equipment.
- Gas cylinders stored upright in a well-ventilated area
- If you suspect a leak, immediately evacuate the area and close the cylinder valve if possible.
- Do not attempt to fix the leak yourself; contact emergency services and the gas supplier.
- Regularly inspect cylinders for rust, dents, or leaks.
- Get trained on the specific gas you're using and its associated safety protocols. Update your knowledge and skills through periodic refresher training.
By incorporating these safety measures into your routine, you can ensure the safe and responsible use of gas cylinders, minimizing risks and maximizing peace of mind. Remember, a little proactive precaution can go a long way in preventing accidents and protecting yourself and those around you.