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| Safety Precaution |
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Specialty gases have those properties which may cause injury or even death if proper precautions are not followed. These properties are outlined below, along wiht those precautions and safety practices which must be followed so that accidents may be prevented. It must be noted that it is impossible to list every conceivable hazard which might occur. The sole purpose here is to list common hazards, precautions, and safety pracices. If you have any questions about the user or handling of specialty gases or their properties, or if a safety hazard is suspected, contact HSG immediately. Do not use specialty gases unless you are thoroughly familiar with their properties, use, and handling. |
| Cylinders |
| All gas cylinders supplied by HSG are labeled in accordance with federal regulations, and valved in accordance with the American National Standards Institute Standard B-57.1 and CGA V-1 Publication for Valve Connections. Never use adapters or change service of a regulator before consulting HSG's Sales/Service Center. If the label is not legible or is missing, or if you do not understand anything contained on the label, do not use the gas and contact HSG. Read the lable on all cylinders prior to use and observe all precautions set forth on the cylinder label. All cylinders must be kept in the upright position and secured prior to use. All cylinders must be used in conjunction with adequate pressure reducing regulators. Piging must be of suitable material for the type, pressure, and temperature of the gas handled. |
| High Pressure Hazard |
Cylinder gases are under high pressure and this pressure can present a hazard. To prevent accidents, always observe the following rules:
- Read and follow precisely the instructions on the cylinder label.
- Never move a cylinder without the cylinder cap in place.
- Always use pressure reducing equipment conditioned for the intended use.
- Always restrain cylinders in service to insure against their upset.
- Never store full cylinders near sources of heat.
- Never tamper with the cylinder valve or cylinder's safety device. If defective, do not attempt repairs. Call HSG immediately.
- Never attempt of transfill gas from one cylinder to another.
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| Inert Gas Hazard |
Argon, carbon dioxide, helium, and nitrogen are all inert gases. Therefore, the hazard they present is that they will not support life and may cause asphyxiation by displacing the oxygen in the air. Argon and carbon dioxide at ambient temperatures are each heavier than air and will tend to concentrate in low places. To insure personnel safety, the following precautions should always be observed:
- Areas where any inert gas is used must be kept well ventilated. A life supporting atmosphere should contain between 19% and 23% oxygen by volume. If there is any potential question as to the oxygen content, an oxygen analyzer with a 0% to 25% scale should be used to check for oxygen.
- None of these inert gases can be detected by any human sense and they will be inhaled just like air. If the oxygen content drops below 19% by volume, the reactions of personnel exposed will depend upon the actual oxygen content and the people themselves. However, they should not expect to experience a choking sensation since this is not a symptom of oxygen deficiency, rather, there many be an immediate loss of consciousness. Never enter any tank, pit, or other confined area where an inert gas is present without first checking the oxygen content.
- If personnel must enter a confined area to which an inert gas is supplied, all supply lines must be disconnected or blanks inserted between valves. The closing of block valves is not adequate protection. After this is done, the space must be adequately flushed with air and the oxygen content checked before entry and during occupancy.
- If personnel must enter a confined space which may contain less than 19% oxygen by volume, a watcher must have a self-contained breathing apparatus available and be proficient in its use. Personnel entering the confined space should wear a rescue harness and a self-contained breathing apparatus. The watcher must have means available to summon help if necessary.
- Carbon dioxide many present a hazard in addition to the hazard caused by its inert qualities. The carbon dioxide content of the blood stream regulates certain bodily functions and may paralyze the respiratory system. OSHA Standards set the threshold limit value to 0.5% concentration by volume and this limit should not be exceeded. If there is the possibility of excessive carbon dioxide in confined space, it is not sufficient to merely check the oxygen concentration; the carbon dioxide concentration must also be checked.
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| Oxidizer Hazard |
| Oxygen supports combustion and life, and normal air contains about 21% oxygen by volume. Should the oxygen concentration rise above this, a definite hazard exists. Materials which normally do not burn in air may burn with explosive violence. Flames are hotter and spread faster. The higher the oxygen concentration, the greater the hazard. A similar hazard may exist in an atmosphere of air pressure since the partial pressure of oxygen will exceed the normal 160mm of mercury.
Industrial and medical oxygen have a purity of at least 99.5% and must be handled with their oxidizing properties in mind. To insure safety, the following precautions must be followed.
- Always refer to oxygen by its name. Never call it "air" or use it as a substitute for compressed air.
- Keep all organic materials, especially oil, grease, wood, cloth, or asphalt, etc., away from contact with oxygen.
- Never attempt to lubricate or repair any equipment used in oxygen service.
- Do not permit smoking or open flames in any area where oxygen is present in concentrations above those of normal air (21% by volume).
- Equipment supplied for use with oxygen is specially cleaned and packaged to prevent contamination. When such equipment is used, care must be taken to see that its cleanliness is maintained.
- Do not enter any confined area where a high concentration of oxygen could exist without first checking the oxygen content with an oxygen analyzer. If personnel must enter a confined area to which oxygen is supplied, all supply lines must be disconnected or blanks inserted between valves. The closing of block valves is not adequate protecion. After this is done, the space must be adequately flushed with air and the oxygen content checked before entry and during occupancy.
- When liquid oxygen is spilled or vented, a white cloud of gas results. Standing in or near this cloud will saturate clothing with oxygen making it extremely flammable. Should this happen, personnel involved should move to a clear area and avoid smoking, open flames, or the sources of ignition for at least one and a half hour.
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| Flammable Hazard |
If hydrocarbon gases are mixed with air or oxygen in a confined space, the mixture will explode if ignited from any cause. Concentrations as low as 1.4% in air can result in an explosive mixture. These gases may also act an asphyxiant by displacing the oxygen in the air. To avoid accidents, observe the following safety precautions.
- Store cylinders containing hydrocarbon gases out-of-doors or in well ventilated areas. Never store with oxygen cylinders or near sources of heat, nor in confined areas.
- Never use these gases if there are any leaks in the cylinders or associated equipment. If leaks occur, you should move the equipment out-fo-doors to a location away from ignition sources and notify your HSG Sales/Service Center immediately.
- Do not permit smoking or open flames in areas where these gases are stored or used.
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| Poison Gases |
| Poison gases such as arsine, methyl bromide, nitric oxide, nitrogen dioxide, phosgene, and phosphine pose serious potential hazards to personnel and therefore require special handling. These products must never be handled except by specially trained personnel who are fully aware of the potential hazards involved and who are equipped with such special personal safety apparatus as is necessary in the handling of these products.
Personnel handling and using highly toxic or poison gases must have available and be trained in the use of, for immediate use in emergencies, gas masks (with cartridge-type adsorbents) or self-contained breathing apparatus of a design approved by the U.S. Bureau of Mines, the National Institute of Occupational Safety and Health (NIOSH), or other approving authority for the particular gas service involved. Gas masks may be used only under conditions where the concentrations of the toxic or poison gas involved will not exceed the rating of the particular gas mask used and where the oxygen content of the atmosphere is not less than 19 percent by volume. Such equipment must be located convenient of the place of work, but kept out of the area most likely to become contaminated.
Storage of highly toxic or poison gases should be outdoors, or in a separate noncombustible building without other occupancy, or in a separate room without other occupancy and of noncombustible construction with a fire resistance rating of at least one hour. Storage locations must be clearly marked and protected against tampering or entry by unauthorized persons. The total quantity of highly toxic or poison gases stored at a user's site should be kept at a minimum.
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| Corrosive Gases |
| Corrosive gases attack human tissue and other materials, and special protective clothing and self-contained breathing apparatus must be used by personnel hadling these substance.
Precautions must be taken to avoid inhalation and/or contacting the skin or eyes with acid or alkaline gases. Goggles of face shields and rubber (or other suitably chemically resistant material) gloves and aprons must be worn when handling these products. Open shoes or sneakers must not be worn when handling these products. Gas masks or selfcontained breathing apparatus must be available with training provided for personnel handling and using corrosive gases.
Areas in which acid or alkaline gases are filled or used should be equipped with an emergency shower and eyewash fountain. Drenching with copious amounts of water is the accepted first aid procedure in the event of exposure of the skin or eyes to corrosive gases. Persons accidentally exposed to such gases should receive prompt attention by a physician.
Acid or alkaline gases should be used only in well-ventilated areas, and quantities stored at a user's site should be kept at a minimum. Examples of acid gases include boron trichloride, boron trifluoride, chlorine, dichlorosilane, hydrogen bromide, hydrogen chloride (anhydrous), hydrogen fluoride, and sulfur dioxide. Examples of alkali gases include ammonia, monomethylamine, dimethylamine.
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| General Precautions |
| All specialty gases have properties which may cause injury or death if proper precautions are not followed. It should never be assumed that all possible hazards or acceptable safety measures have been complied without the exercise of common sense and prudence in the handling of any product. In most instances, hazards are created because of improper application or the misuse of the gas or its container. Another major cause of accidents in the use of gases is improper installation and failure to provide proper regulators, valves, piping and tubing. |
| Always Remember |
Precautionary information on the safe handling of gases listed in this catalog is provided on Material Safety Data Sheets (MSDS) which are issued to customers for each product sold. We urge you to read and thoroughly understand the information contained in the applicable MSDS before using any of the gases in the catalog.
- Cylinder contents are identified by a decal on the container. If this decal is missing or not legible, call your supplier for instrucions. Users of specialty gases are urged to be certain all employees read and follow the precautionary information on all gas cylinders, as well as the pertinent MSDS forms.
- Always follow exactly the operation instructions of gas equipment manufacturers.
- It is the responsibility of the user to be certain that all employees are familiar with the specific properties and proper handling techniques applicable to each gas used. There are literally hundreds of gases and gas mixtures which are in specialty service and which may present hazards not mentioned in this catalog. If there is ever any doubt about any gas or gas mixture, contact your HSG Sales/Service Center.
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| Note |
| The information and recommendations contained herein represent current information on the safe handling of specialty gases. No warranty, guarantee or representation is made by HSG as to the completeness or sufficiency of these suggestions. Gases, if improperly used or handled, may be hazardous. It is imperative that each user of specialty gases be thoroughly knowledgeable as to the use, handling, storage, and properties of the gases and follow precisely all safety precautions. It should not be assumed that all possible hazards or applicable precautionary measures are contained in this catalog or that other additional measures may not be required under particular or exceptional conditions or circumstances. HSG does not, therefore, assume any responsibility for these suggestions or for your use, handling, or storage of any gases. |
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