While industrial and specialty gases have many wonderful uses, they can also bring new safety hazards to the workplace. It is important that any site using gases should plan to avoid these potential problems by implementing the correct training and procedures. Our team at Liberty can help you accomplish this.
High Pressure Hazards
Gases are often transported in high pressure cylinders. These cylinders all have a valve at the top to which is attached a regulator so that gas can be drawn off at desired rates. If a valve or regulator is struck and broken off of the cylinder, the cylinder will move violently depending on the remaining pressure. Also, the piping or vessels into which high pressure gas is introduced must be able to support such pressures or they could rupture violently
A life-supporting atmosphere should contain between 19% and 23% oxygen by volume. Some industrial gases are inert and cannot be detected by any human sense. If these gases accumulate, a zone could be created that is outside of this life-supporting range. Any person entering this zone could be endangered. Other gases may be toxic to breathe and doing so must also be avoided.
Extreme Cold Hazards
Liquid or cryogenic gases are extremely cold, reaching temperatures as low as -320°F for nitrogen. Human contact with such low temperatures results in immediate destruction of tissue or can cause severe frostbite.
Certain gases are flammable and when mixed with air or oxygen can become explosive in a confined space and when ignited from any cause.
Moving Cylinders and Containers
Cylinders and containers must always be moved carefully. Mishandling that results in a damaged valve or ruptured cylinder can expose personnel to the hazards associated with these gases. In addition, most gas cylinders are heavy and bulky. A cylinder striking someone or pinching a finger, toe, or other extremity is a common cause of injury. For these reasons, all cylinder handlers must always wear certain minimum personal protective equipment prescribed by OSHA:
- Gloves to protect the hands against common pinching injuries.
- Safety glasses to protect the eyes against injuries associated with pressure release.
- Safety shoes with metatarsal supports to protect against foot injuries from falling cylinders.
- Before moving a cylinder to the storage area or point of use or before returning the cylinder to the supplier, ensure the following:
- The outlet valve is fully closed.
- The outlet valve dust plug or pressure cap is on tight for cylinders equipped with these protection devices.
- The valve protection cap is properly secured in place on cylinders with neck threads.
Note: Valve caps must always be in place while moving or transporting cylinders or when they are in storage.
While moving full or empty cylinders:
- Always use carts or hand trucks designed for this purpose.
- Never drop cylinders or allow them to strike each other violently.
- Never lift cylinders by the cap or with a lifting magnet.
- After moving a cylinder to its point of use, secure the cylinder in place. Use cylinder stands, clamps, or other securing devices recommended by your supplier.
Opening and Closing Valves
Observing a few simple rules when opening and closing valves can prevent damage to valves and equipment and add years of useful service life to the valves. The proper way to open any cylinder valve is to first crack the valve, then open it slowly by turning the handle or stem counterclockwise. This allows equipment to gradually adjust to full pressure. Stop turning as soon as there is any resistance. Turning the valve handle or stem too far in the open position can jam the stem, causing damage and leaks and preventing later closure. Likewise, overtightening when closing a valve can damage or permanently distort the seat and result in leakage.
Note: Never open a cylinder valve that is not connected to a pressure regulating device.
Helium Cylinder Safety Precautions
What to do?
Read, understand and observe the safety precautions on the cylinder neck label and
the warning label on the side of the cylinder.
Store and use helium cylinders in a well ventilated area and in an upright secured
position so they cannot be knocked over.
Cylinders must be chained to a wall or placed in a safety stand at all times.
Close the cylinder valve after each use and when cylinder is empty. Remove the
regulator and replace the cylinder protective cap before transporting any helium
Use a cylinder cart to move cylinders.
Always open cylinder valves very, very slowly. Stand to one side of the cylinder when
opening the valve; never stand directly in front of the cylinder.
Always keep helium stored in a well ventilated area.
What not to do?
Do not allow anyone to inhale helium from cylinders or filled balloons.
Do not open the cylinder valve before attaching a balloon regulator on the cylinder
Do not allow children or any unauthorized persons to handle cylinders or use balloon
Never leave a cylinder unattended in a public area.
Never use any balloon regulator, cylinder or valve fitting that is damaged, leaking or
malfunctioning. Have the product repaired or replaced immediately.
Do not drop, drag, tip over or roll the helium cylinder on its side.
Fumes and Gases Can Harm Your Health
Keep your head out of the fumes. Do not breathe fumes and gases caused by the arc. Use enough ventilation. The type and the amount of fumes and gases depend on the equipment and supplies used. Air samples can be used to find out what respiratory protection is needed.
Provide enough ventilation wherever welding and cutting are performed. Proper ventilation can protect the operator from the evolving fumes and gases. The degree and type of ventilation needed will depend on the specific welding and cutting operation. It varies with the size of the work area, on the number of operators, and on the types of materials to be welded or cut. Potentially hazardous materials may exist in certain fluxes, coatings, and filler metals. They can be released into the atmosphere during welding and cutting. In some cases, general natural-draft ventilation may be adequate. Other operations may require forced-draft ventilation, local exhaust hoods or booths, or personal filter respirators or air-supplied masks. Welding inside tanks, boilers, or other confined spaces requires special procedures, such as the use of an air-supplied hood or hose mask.
Sample the welding atmosphere and check ventilation system if workers develop unusual symptoms or complaints. Measurements may be needed to determine whether adequate ventilation is being provided. A qualified person, such as an industrial hygienist, should survey the welding operations and surrounding environment.
Do not weld on plate contaminated with unknown material. The fumes and gases which are formed could be hazardous to your health. Remove all paint and galvanized coatings before welding.