osha air compressor safety valve factory

An OSHA COMPRESSED AIR SAFETY SHUT-OFF VALVES should be placed immediately after the air control shut off valve and before the hose on a compressor, and after each discharge port that a hose is connected to.

Before starting the compressor the air control valve should be closed completely. When the compressor unloads, open the air shut off control valve very slowly. Full port ball valves tend to work better than gate or butterfly type valves.

The air shut off control valve must be fully open for the OSHA COMPRESSED AIR SAFETY SHUT-OFF VALVES to work. Some portable air compressor manufacturers recommend start-up with the air control valve slightly open. In this case you may have to close the valve and reopen it slowly to the full open position, or wait for the safety shut-off valve to reset itself.

If the OSHA COMPRESSED AIR SAFETY SHUT-OFF VALVES fails to operate despite meeting all condi-tions, check the hose line for obstructions or a hose mender restricting normal air flow.

• Turn on air supply slowly (to avoid tripping OSHA safety valve). Prior to fully reaching operation conditions, the OSHA COMPRESSED AIR SAFETY SHUT-OFF VALVES should suddenly activate and stop air flow.

• If the OSHA COMPRESSED AIR SAFETY SHUT-OFF VALVE is not activated the unit should be disconnected and the lower flow range OSHA COMPRESSED AIR SAFETY SHUT-OFF VALVES should be used. This means you need to use a different valve with a lower scfm range.

• At temperatures below 40°F ensure that OSHA COMPRESSED AIR SAFETY SHUT-OFF VALVES are not subject to icy conditions which may prevent proper functioning.

Thank you for your letter dated January 31 concerning your constituent, Mr. James Lyle McCloy II, President of Compressed Air Parts Company. Mr. McCloy is concerned about the lack of enforcement by the Occupational Safety and Health Administration (OSHA) of its rules requiring safety check valves on compressed air equipment. I apologize for the delay of this response.

As Mr. Roy Gurnham of my staff discussed with Mr. Mark Staudohar of your office in mid-February when he called to explain we could not meet with Mr. McCloy at the time, OSHA continues to recognize the need for safety check valves and is concerned that accidents have occurred because such valves were not provided as required. We will remind our compliance officers of the importance of this provision and that their inspections should include a review of such equipment as appropriate.

As you may be aware, the State of Arizona is responsible for occupational safety and health enforcement within the State under a plan approved and monitored by Federal OSHA. Under its plan, Arizona adopts standards identical to those promulgated by Federal OSHA and utilizes equivalent enforcement procedures. If your constituent wishes to discuss safety and health enforcement in Arizona, we suggest that he contact the Arizona industrial Commission at the following address:

The enclosed information is sent for your consideration. Please investigate this matter and forward to me the information for response to my constituent, Mr. James Lyle McCloy II, President of Compressed Air Parts Company.

Introducing our product in mid 1972, with several other manufacturers, sales were quite brisk and the Department of Labor was very active insuring compliance. Since early 1976 enforcement has been very `spotty". As of this time only ourselves and one other manufacturer are still providing valves to meet Federal Regulations. Fortunately we have been the primary source.

Recently we were dismissed from a One Million Dollar ($1,000,000) product liability suit in which it was determined that the air compressor in use was not equipped with a safety check valve as required. This incident took place on a Federally funded Interstate bridge repair contract. Also, there is currently a multi-million suit concerning the lack of a safety check valve (actually there was a valve on the compressor but was removed for unknown reasons). In that case a worker has a severe head injury and has been in a nursing home for two years and cannot recognize his family.

Application. This section applies to compressed air receivers, and other equipment used in providing and utilizing compressed air for performing operations such as cleaning, drilling, hoisting, and chipping. On the other hand, however, this section does not deal with the special problems created by using compressed air to convey materials nor the problems created when men work in compressed air as in tunnels and caissons. This section is not intended to apply to compressed air machinery and equipment used on transportation vehicles such as steam railroad cars, electric railway cars, and automotive equipment.

All new air receivers installed after the effective date of these regulations shall be constructed in accordance with the 1968 edition of the A.S.M.E. Boiler and Pressure Vessel Code Section VIII, which is incorporated by reference as specified in § 1910.6.

All safety valves used shall be constructed, installed, and maintained in accordance with the A.S.M.E. Boiler and Pressure Vessel Code, Section VIII Edition 1968.

Installation. Air receivers shall be so installed that all drains, handholes, and manholes therein are easily accessible. Under no circumstances shall an air receiver be buried underground or located in an inaccessible place.

Drains and traps. A drain pipe and valve shall be installed at the lowest point of every air receiver to provide for the removal of accumulated oil and water. Adequate automatic traps may be installed in addition to drain valves. The drain valve on the air receiver shall be opened and the receiver completely drained frequently and at such intervals as to prevent the accumulation of excessive amounts of liquid in the receiver.

Every air receiver shall be equipped with an indicating pressure gage (so located as to be readily visible) and with one or more spring-loaded safety valves. The total relieving capacity of such safety valves shall be such as to prevent pressure in the receiver from exceeding the maximum allowable working pressure of the receiver by more than 10 percent.

Safety appliances, such as safety valves, indicating devices and controlling devices, shall be constructed, located, and installed so that they cannot be readily rendered inoperative by any means, including the elements.

There shall be retained one or more licensed physicians familiar with and experienced in the physical requirements and the medical aspects of compressed air work and the treatment of decompression illness. He shall be available at all times while work is in progress in order to provide medical supervision of employees employed in compressed air work. He shall himself be physically qualified and be willing to enter a pressurized environment.

No employee shall be permitted to enter a compressed air environment until he has been examined by the physician and reported by him to be physically qualified to engage in such work.

In the event an employee is absent from work for 10 days, or is absent due to sickness or injury, he shall not resume work until he is reexamined by the physician, and his physical condition reported, as provided in this paragraph, to be such as to permit him to work in compressed air.

After an employee has been employed continuously in compressed air for a period designated by the physician, but not to exceed 1 year, he shall be reexamined by the physician to determine if he is still physically qualified to engage in compressed air work.

Such physician shall at all times keep a complete and full record of examinations made by him. The physician shall also keep an accurate record of any decompression illness or other illness or injury incapacitating any employee for work, and of all loss of life that occurs in the operation of a tunnel, caisson, or other compartment in which compressed air is used.

Records shall be available for the inspection of the Secretary or his representatives, and a copy thereof shall be forwarded to OSHA within 48 hours following the occurrence of the accident, death, injury, or decompression illness. It shall state as fully as possible the cause of said death or decompression illness, and the place where the injured or sick employee was taken, and such other relative information as may be required by the Secretary.

A medical lock shall be established and maintained in immediate working order whenever air pressure in the working chamber is increased above the normal atmosphere.

Be provided with oxygen lines and fittings leading into external tanks. The lines shall be fitted with check valves to prevent reverse flow. The oxygen system inside the chamber shall be of a closed circuit design and be so designed as to automatically shut off the oxygen supply whenever the fire system is activated.

Be provided with sources of air, free of oil and carbon monoxide, for normal and emergency use, which are capable of raising the air pressure in the lock from 0 to 75 p.s.i.g. in 5 minutes.

Identification badges shall be furnished to all employees, indicating that the wearer is a compressed air worker. A permanent record shall be kept of all identification badges issued. The badge shall give the employee"s name, address of the medical lock, the telephone number of the licensed physician for the compressed air project, and contain instructions that in case of emergency of unknown or doubtful cause or illness, the wearer shall be rushed to the medical lock. The badge shall be worn at all times-off the job, as well as on the job.

For each 8-hour shift, a record of employees employed under air pressure shall be kept by an employee who shall remain outside the lock near the entrance. This record shall show the period each employee spends in the air chamber and the time taken from decompression. A copy shall be submitted to the appointed physician after each shift.

In the event it is necessary for an employee to be in compressed air more than once in a 24-hour period, the appointed physician shall be responsible for the establishment of methods and procedures of decompression applicable to repetitive exposures.

Except in emergency, no employees employed in compressed air shall be permitted to pass from the working chamber to atmospheric pressure until after decompression, in accordance with the procedures in this subpart.

The lock attendant in charge of a man lock shall be under the direct supervision of the appointed physician. He shall be stationed at the lock controls on the free air side during the period of compression and decompression and shall remain at the lock control station whenever there are men in the working chamber or in the man lock.

Except where air pressure in the working chamber is below 12 p.s.i.g., each man lock shall be equipped with automatic controls which, through taped programs, cams, or similar apparatus, shall automatically regulate decompressions. It shall also be equipped with manual controls to permit the lock attendant to override the automatic mechanism in the event of an emergency, as provided in paragraph (g)(1)(viii) of this section.

Except where air pressure is below 12 p.s.i.g. and there is no danger of rapid flooding, all caissons having a working area greater than 150 square feet, and each bulkhead in tunnels of 14 feet or more in diameter, or equivalent area, shall have at least two locks in perfect working condition, one of which shall be used exclusively as a man lock, the other, as a materials lock.

The man lock shall be large enough so that those using it are not compelled to be in a cramped position, and shall not have less than 5 feet clear head room at the center and a minimum of 30 cubic feet of air space per occupant.

Man locks shall have an observation port at least 4 inches in diameter located in such a position that all occupants of the man lock may be observed from the working chamber and from the free air side of the lock.

The headroom in the special decompression chamber shall be not less than a minimum 7 feet and the cubical content shall provide at least 50 cubic feet of airspace for each employee. For each occupant, there shall be provided 4 square feet of free walking area and 3 square feet of seating space, exclusive of area required for lavatory and toilet facilities. The rated capacity shall be based on the stated minimum space per employee and shall be posted at the chamber entrance. The posted capacity shall not be exceeded, except in case of emergency.

Adequate toilet and washing facilities, in a screened or enclosed recess, shall be provided. Toilet bowls shall have a built-in protector on the rim so that an air space is created when the seat lid is closed.

At all times there shall be a thoroughly experienced, competent, and reliable person on duty at the air control valves as a gauge tender who shall regulate the pressure in the working areas. During tunneling operations, one gauge tender may regulate the pressure in not more than two headings: Provided, That the gauge and controls are all in one location. In caisson work, there shall be a gauge tender for each caisson.

The low air compressor plant shall be of sufficient capacity to not only permit the work to be done safely, but shall also provide a margin to meet emergencies and repairs.

Low air compressor units shall have at least two independent and separate sources of power supply and each shall be capable of operating the entire low air plant and its accessory systems.

The capacity, arrangement, and number of compressors shall be sufficient to maintain the necessary pressure without overloading the equipment and to assure maintenance of such pressure in the working chamber during periods of breakdown, repair, or emergency.

Duplicate low-pressure air feedlines and regulating valves shall be provided between the source of air supply and a point beyond the locks with one of the lines extending to within 100 feet of the working face.

Gauges indicating the pressure in the working chamber shall be installed in the compressor building, the lock attendant"s station, and at the employer"s field office.

Exhaust valves and exhaust pipes shall be provided and operated so that the working chamber shall be well ventilated, and there shall be no pockets of dead air. Outlets may be required at intermediate points along the main low-pressure air supply line to the heading to eliminate such pockets of dead air. Ventilating air shall be not less than 30 cubic feet per minute.

The air in the workplace shall be analyzed by the employer not less than once each shift, and records of such tests shall be kept on file at the place where the work is in progress. The test results shall be within the threshold limit values specified in Subpart D of this part, for hazardous gases, and within 10 percent of the lower explosive limit of flammable gases. If these limits are not met, immediate action to correct the situation shall be taken by the employer.

The temperature of all working chambers which are subjected to air pressure shall, by means of after-coolers or other suitable devices, be maintained at a temperature not to exceed 85 deg. F.

Forced ventilation shall be provided during decompression. During the entire decompression period, forced ventilation through chemical or mechanical air purifying devices that will ensure a source of fresh air shall be provided.

Whenever heat-producing machines (moles, shields) are used in compressed air tunnel operations, a positive means of removing the heat build-up at the heading shall be provided.

All lighting in compressed-air chambers shall be by electricity exclusively, and two independent electric-lighting systems with independent sources of supply shall be used. The emergency source shall be arranged to become automatically operative in the event of failure of the regularly used source.

The minimum intensity of light on any walkway, ladder, stairway, or working level shall be not less than 10 foot-candles, and in all workplaces the lighting shall at all times be such as to enable employees to see clearly.

All electrical equipment and wiring for light and power circuits shall comply with the requirements of Subpart K of this part for use in damp, hazardous, high temperature, and compressed air environments.

Sanitary, heated, lighted, and ventilated dressing rooms and drying rooms shall be provided for all employees engaged in compressed air work. Such rooms shall contain suitable benches and lockers. Bathing accommodations (showers at the ratio of one to 10 employees per shift), equipped with running hot and cold water, and suitable and adequate toilet accommodations, shall be provided. One toilet for each 15 employees, or fractional part thereof, shall be provided.

While welding or flame-cutting is being done in compressed air a firewatch with a fire hose or approved extinguisher shall stand by until such operation is completed.

The power house, compressor house, and all buildings housing ventilating equipment, shall be provided with at least one hose connection in the water line, with a fire hose connected thereto. A fire hose shall be maintained within reach of structures of wood over or near shafts.

In addition to fire hose protection required by this subpart, on every floor of every building not under compressed air, but used in connection with the compressed air work, there shall be provided at least one approved fire extinguisher of the proper type for the hazard involved. At least two approved fire extinguishers shall be provided in the working chamber as follows: One at the working face and one immediately inside the bulkhead (pressure side). Extinguishers in the working chamber shall use water as the primary extinguishing agent and shall not use any extinguishing agent which could be harmful to the employees in the working chamber. The fire extinguisher shall be protected from damage.

Highly combustible materials shall not be used or stored in the working chamber. Wood, paper, and similar combustible material shall not be used in the working chamber in quantities which could cause a fire hazard. The compressor building shall be constructed of non-combustible material.

In tunnels 16 feet or more in diameter, hanging walkways shall be provided from the face to the man lock as high in the tunnel as practicable, with at least 6 feet of head room. Walkways shall be constructed of noncombustible material. Standard railings shall be securely installed throughout the length of all walkways on open sides in accordance with Subpart M of this part. Where walkways are ramped under safety screens, the walkway surface shall be skidproofed by cleats or by equivalent means.

Bulkheads used to contain compressed air shall be tested, where practicable, to prove their ability to resist the highest air pressure which may be expected to be used.

Each equipment modification, repair, test, calibration or maintenance service shall be recorded by means of a tagging or logging system, and include the date and nature of work performed, and the name or initials of the person performing the work.

Compressors used to supply air to the diver shall be equipped with a volume tank with a check valve on the inlet side, a pressure gauge, a relief valve, and a drain valve.

The output of air compressor systems shall be tested for air purity every 6 months by means of samples taken at the connection to the distribution system, except that non-oil lubricated compressors need not be tested for oil mist.

An inflatable flotation device capable of maintaining the diver at the surface in a face-up position, having a manually activated inflation source independent of the breathing supply, an oral inflation device, and an exhaust valve shall be used for SCUBA diving.

Surface-supplied air masks and helmets shall have a minimum ventilation rate capability of 4.5 acfm at any depth at which they are operated or the capability of maintaining the diver"s inspired carbon dioxide partial pressure below 0.02 ATA when the diver is producing carbon dioxide at the rate of 1.6 standard liters per minute.

When using a portable air compressor on a worksite, what component should (almost) always be part of the job? The answer is a safety check valve (SCV), properly installed between the compressor and the hose. In fact, if your air hose has an inside diameter of more than a ½ inch, OSHA requires a SCV to be installed at the source of the air supply to shut off the air automatically in case of hose failure. (If a check valve is not being used, OSHA requires a safety cable, such as Dixon’s King™ safety cable, to be attached to the hose.) But selecting the right safety check valve is an important but often times confusing task. There are many factors that play into that decision: air pressure, tool flow rate, compressor flow rate, the size of your hose, and the length of your hose, among them. Here’s a quick guide to helping make that decision an easier one.

Safety check valves are used to shut off flow in the event of a full-flow condition, which could be caused by a line break or damaged tool. During a full-flow condition, the compressor blasts air like a geyser and can whip the hose around the worksite, potentially causing serious injury to personnel or damage to equipment.

As air passes through the safety check valve, the valve flutters back and forth, allowing the air to bypass the valve and go downstream to the tool. In the event of a hose failure, the sudden rush of air through the valve causes it to slam shut, eliminating potential danger. A pin-sized hole in the valve allows a small amount of air to escape, but not enough to whip the hose around. That’s why you’ll still hear some air hissing at the end of the hose, even when the safety valve is engaged. Once the hose is repaired and the full flow condition goes away, the safety check valve will reset itself, allowing airflow to resume. Without this feature, you would have to manually reset the valve, a time-consuming task.

What is the maximum airflow possible, in SCFM, through your air hose, at the end of the length of the hose? (Note: If the hose you’re using is more than 100 feet long, contact Dixon for recommendations.)

It’s very important to select both the correct hose ID as well as the correct size spring within the valve. If the spring is too large or too small, it will cause the valve to shut prematurely or not to check at all.

The safety shut-off valve taper (NPT) size must be the same as the nominal ID size of the airline on which it is used. (Note: Never increase or decrease the hose size from the compressor to the tool or from the compressor to the manifold.)

To avoid nuisance cut-offs, the SCV selected should have a cut-off range of 110% of the maximum anticipated airflow to the tool, or tools, to be used. (As a general rule, you want your tool consuming less flow than the cut-off range of the SCV and you want your compressor capable of supplying more flow than the cut off range of the SCV.)

The maximum SCFM of the supply side airline must be above the cut-off range of the valve. The cut-off range of Dixon"s shut-off valves is given at 90 PSI. To determine the cut-off range at other PSIs, please refer to Dixon’s Cut-off Rate Chart on our product spec sheet.

In certain applications, like pile driving or sand blasting, where a surge of air is needed right away, you’ll have to use a safety cable since a check valve won’t work properly.

In closing, whenever you’re using an air compressor for jobs other than the ones mentioned directly above, it’s important to include a safety check valve in the system. Knowing how to select the proper SCV for the job creates a safer, more efficient worksite. As always, if you have any questions about safety check valves, please call a Dixon representative at 877.963.4966.

OSHA valve is a safety device that shuts off air flow to hose in case of excess pressure. Provides safety to the operator and surroundings. Made of heavy-duty steel. Use with 3/4’’ diameter hoses and 185-210 cubic feet per minute (CFM) of air pressure.

(a) Air compressor discharge lines having a block valve between the air receiver and compressor shall have a pressure relieving safety device installed in the line between the compressor and block valve. The pressure relieving safety device shall be set to open at a pressure not to exceed the rated working pressure of the cylinder. The relieving capacity of the pressure relieving safety device shall be such as to prevent a rise of pressure in the compressor cylinder of more than 10 percent above its maximum allowable working pressure, and the discharge shall be to a safe place.

(b) Air compressor intake lines shall not be located in toxic atmospheres or atmospheres containing explosive concentrations of flammable gases or vapors.

____ Are safety chains or other suitable locking devices used at couplings of high pressure hose lines where a connection failure would create a hazard?

____ Is it prohibited to use compressed air to clean up or move combustible dust, if such action could cause the dust to be suspended in the air and cause a fire or explosion?

Is it prohibited to use compressed air to clean up or move combustible dust if such action could cause the dust to be suspended in the air and cause a fire or explosion hazard?

The OSHA Safety Standard Regulation 29CFR CHXVII Paragraph 1926.302(b)(7) states:   All hoses exceeding 1/2-inch inside diameter shall have a safety device at the source of supply or branch line to reduce pressure in case of hose failure.

Prevent dangerous air hose whips and accidents.   Protect your most important assets: Your employees and their equipment.   OSHA COMPRESSED AIR SAFETY SHUT-OFF VALVESoffers simple but efficient protection to pneumatic systems in the event of a broken compressed air hose or pipe.

OSHA says reduce your slips, trips and falls. Slips, trips and falls constitute the majority of general industry accidents, which cause 15% of all accidental deaths, and are second only to motor vehicles as a cause of fatalities. The OSHA standard for walking and working surfaces apply to all permanent places of employment, except where only domestic, mining, or agricultural work is performed.www.osha.gov

Consider adding reels to increase safety & efficiency with your electrical cords, welding cables, air hose, oil, grease, liquid/water or fuel hoses.  This could be one of your most effective equipment additions you’ll ever make…as well as one of the safest!

Provide a Safer Work EnvironmentHose reels decrease you chances of injuries from tripping hazards.  Reduce accidents and insurance expense:  Slips, trips and falls are the leading cause of work stoppage in industry. Reels can help you meet OSHA Safety Requirements.

Reels are used to transfer air, water, motor oil, transmission fluid, grease, gear oil, anti-freeze, diesel fuels, welding gases, fuel oil, liquid pesticides, fertilizers, detergents, hydraulic oils, cutting oils, printing inks, solvents, chemicals, and blacktop sealers.

Probably one of the largest uses of hose reels is for Compressed Air. Compressed air is clean, readily available, and simple to use. As a result, compressed air is often chosen for applications for which other energy sources are more economical.  Inappropriate uses of compressed air include any application that can be done more effectively or more efficiently by a method other than compressed air.

Don’t WASTE your Compressed Air. Check your facility for wasteful and perhaps even unsafe uses of compressed air. Bottom Line:  Invest in durable, quality reels that make hoses, cords and cables more productive, keep them easily accessible and make them last longer.

Pressure is the measure of potential energy stored within compressed air. Pressure is measured in pounds per square inch (psi). In general, most industrial compressed air systems operate at pressures between 80 and 120 psi. The electrical equivalent of pressure is voltage.

Flow is the volume of compressed air traveling through an air gun during a given period of time. Flow is measured in cubic feet per minute (cfm). In general, the higher the flow, an increased capacity (larger diameter) air line, and an increased capacity (larger horsepower) air compressor will be required. The electrical equivalent of flow is amperage.

Thrust is the effective force produced by an air gun and is generated from the combination of air pressure and air flow. Thrust is measured in pounds (lbs) and the higher the thrust, the more cleaning force is available. Ideally, thrust of say 10 pounds is capable of moving up to a 10 pound object. The electrical equivalent of thrust is wattage.

Guardair does not recommend operating our air guns at pressures over 120 psi. Although the structural integrity of Guardair safety air guns have been tested and proven well above 120 psi, they have been designed to operate most efficiently and to meet the OSHA standard regarding output pressure at air pressures between 80 and 120 psi. Consequently, Guardair cannot certify that our air guns meet this OSHA standard at pressures in excess of 120 psi.

In general, Guardair safety air guns featuring a ¼" NPT inlets require ¼" ID or larger air lines. Air guns with a 3/8" NPT inlets require 3/8" ID or larger air lines. Air guns with a ¾" NPT inlet require ¾" ID or larger air lines. To ensure rated thrust, air lines can always be sized larger than required, but not smaller.

Be sure that fittings and/or connectors do not restrict the air flow in any manner. Use fittings that are rated the same size, or larger, for a given air line size. Where recommended use Guardair High Flow connectors.

A good rule of thumb states that air compressors generate approximately 4.5 cubic feet per minute (cfm) of compressed air per horsepower (HP) on a continuous basis. To size a compressor (HP), divide the air requirement (cfm) by 4.5. Refer to the specification on your compressor for more information.

Absolutely not! Blocking the side ports does not provide extra power at the nozzle tip. Thrust is actually reduced because ambient outside air cannot be drawn into the outgoing air stream. In addition, the nozzle is now OSHA non-compliant.

Third, ensure that the operating air pressure measures between 80 and 120 psi. Click for video demo, including set-up and operation, of the HydroForce.