Leaks flammable gases

Shut off all electrical power and remove all sources of ignition (heat, sparks, etc.) from the area to prevent ignition of a leaking flammable gas. 

Propylene is a colorless gas under normal conditions, has anesthetic properties at high concentrations, and can cause asphyxiation. It does not irritate the eyes and its odor is characteristic of olefins. Propjiene is a flammable gas under normal atmospheric conditions. Vapor-cloud formation from Hquid or vapor leaks is the main ha2ard that can lead to explosion. The autoignition temperature is 731 K in air and 696 K in oxygen (80). Evaporation of Hquid propylene can cause skin bums. Propylene also reacts vigorously with oxidising materials. Under unusual conditions, eg, 96.8 MPa (995 atm) and 600 K, it explodes. It reacts violentiy with NO2, N2O4, and N2O (81). Explosions have been reported when Hquid propylene contacts water at 315—348 K (82). Table 8 shows the ratio TJTp where is the initial water temperature, and T is the superheat limit temperature of the hydrocarbon. 

When reading an accident report, look for the things that are not said. For example, a gland leak on a liquefied flammable gas pump caught fire and caused considerable damage. The report drew atten-... 

Gases Flammable gases are usually very easily ignited if mixed with air. Flammable gases are often stored under pressure, in some cases as a hquid. Even small leaks of a liquefied flammable gas can form relatively large quantities of gas, which is ready for combustion. 

Dry powders are effeetive on flammable liquid or eleetrieal fires. Speeial powders are available for use on metals. Dry powder extinguishers may be used on Class C fires, ineluding gases and liquefied gases in the form of a liquid spillage or a liquid or gas leak. This must be aeeompanied by other aetions, e.g. stopping the leak this is neeessary to avoid aeeumulation of an unburned flammable gas-air mixture whieh eould subsequently result in an explosion. Aetivation may be automatie by a deteetion system, or manual. 

The prevention of leaks, sinee liquid may generate large quantities of flammable gas. 

Provide an emergency response plan for flammable gas leaks in ihc. 

A similar incident occurred on a solids drier. Before maintenance started, the end cover was removed, and the inlet line was disconnected. When maintenance was complete, the end cover was replaced, and at the same time the inlet pipe was reconnected. The final job was to cut off the guide pins on the cover with a cutting disc. The atmosphere outside (but not inside) the drier was tested, and no flammable gas was detected. While cutting was in progress, an explosion occurred in the drier. Some solvent had leaked into the inlet pipe and then drained into the drier [19]. 

Before a permit to weld or carry out other hot work is issued, it is normal practice to make sure there are no leaks of flammable gas or liquid nearby and no abnormal conditions that make a leak likely. The meaning of nearby depends on the nature of the material that might leak, the slope of the ground, and so on. For highly flammable liquids, 15 m is often used. 

Many leaks have been discussed under other headings, including leaks that occurred during maintenance (Chapter 1), as the result of human error (Chapter 3), or as the result of overfilling storage tanks (Section 5.1). Other leaks have occurred as the result of pipe or vessel failures (Chapter 9), while leaks of liquefied flammable gas are discussed in Chapter 8 and leaks from pumps and relief valves in Chapter 10. 

On many occasions employees have entered a cloud of flammable gas or vapor to isolate a leak. In the incident described in Section 7.2.1 (d), this was done to avoid shutting down the plant. More often, it has been done because there was no other way of stopping the leak. The persons concerned would have been badly burned if the leak had ignited while they w ere inside the cloud. 

It is possible to measure the extent of a leak of flammable gas or vapor with a combustible gas detector. If the leak is small, a person may be allowed (but not expected) to put his hands, suitably protected, inside the flammable cloud. But only in the most exceptional circumstances should a person be allowed to put more of his body into the cloud. 

A leak in another heat exchanger allowed flammable gas to enter a cooling-water return line. The gas was ignited by welding, which was being carried out on the cooling tower. The atmosphere had been tested before work started, five hours earlier (see Section 1.3.2). 

These explosions in air are usually the result of the release of flammable gas and/or mists by leaks, rupture of equipment, or rupture of safety relierdng devices and release to the atmosphere, which become ignited by spark, static electricity, hot surfaces, and many other... 

The risk with liquefied petroleum gas in cylinders is significantly greater than with a highly flammable liquid in drums because of the potential for rapid release of heavy flammable gas. In a fire around a cylinder there is a potential BLEVE hazard (see p. 178) igiution of a leak from a valve will cause a jet fire. 

The PSM Rule requires all PrHAs to address "any previous incident which had a likely potential for catastrophic consequences in the workplace," 29 CFR 1910.119(e)(3)(ii). An incident is an unplanned event that may or may not result in injuries and/or loss. For example, an incident might involve a flammable gas leak that does not ignite. An accident, on the other hand, is an unplanned event that actually leads to personal injury, property damage, environmental damage, and/or business interruption losses, such as the ignition of a flammable gas leak resulting in burns and fire damage. 

Using conductive shoes and changing the location of the toolbox solved this problem. This example may have been a disaster if the pipefitter was repairing a flammable gas leak, for example, during an emergency situation. 

B. Damage by confined explosions due to accumulation and ignition of flammable mixtures arising from small process leaks, e.g., flammable gas buildup in analyzer houses, in enclosed drains, around submerged tanks... 

Glycol/water mixture leaks from jacket into blender, reacts with aluminum powder and sodium hydrosulfite, and initiates exothermic decomposition No—N2 atmosphere, confinement in blender R NOAA Worksheet indicates combining sodium hydrosulfite with ethylene glycol is "explosive due to vigorous reaction or reaction products may produce detonation," "may cause fire," and indicates "flammable gas generation" and "heat generation by chemical reaction, may cause pressurization"... 

Equipment such as pumps, compressors, tanks, and vessels associated with large inventories of flammable gas or liquid (>5000 gallons) should be provided with equipment emergency isolation valves to stop the flow of material if a leak occurs. For example, the decision to add emergency isolation valves to the inlet and outlet of a compressor is dependent on the flammability of the gas, its pressure, and the quantity of gas in the associated piping and vessels. 

The hazards specific to the handling of a flammable gas in a compressor system are internal and external explosions and jet fires caused by ignition of gas escaping from a leak or break ... 

A good chemist takes pride in his apparatus. He diameter of 6 millimeters lit snugly into the holes in makes it. with great, care—not just for looks but. the usual rubber stoppers. Rubber tubing of an in-more important, for safety. An apparatus that leaks side diameter of % fits over the 6mm glass tubes, flammable gas can be very dangerous. To determine the right size stoppers to use in the... 

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