Handling Flammable Substances

A vacuum condenser has vacuum equipment (such as steam jets) pulling the noncondensibles out of the cold end of the unit. A system handling flammable substances has a control valve between the condenser and Jets (an air bleed is used to control nonflammable systems). The control method involves derating part of the tube surface by blajiketing it with noncondensibles that exhibit poor... 

U S Enviromental Protection Agency, 1997. Lightning Hazard to facilities handling flammable substances, EPA 550-F-97-002C. 

Handle flammable substances only in areas Ifee of ignition sources. Besides open flames, ignition sources include electrical equipment (especially motors), static electricity, and, for some materials (e.g., carbon disulfide), even hot surfaces. Check the work area for flames or ignition sources before using a flammable substance. Before igniting a flame, check for the presence of a flammable substance. 

This recommended practice is intended to apply to faciUties that (/) handle or store flammable or explosive substances in such a manner that a release of ca 5 t of gas or vapor could occur in a few minutes and (2) handle toxic substances. The threshold quantity for the toxic materials would be determined using engineering judgment and dispersion modeling, based on a potential for serious danger as a result of exposures of <1 h. 

In this research, the main focus is safety in a chemical company handling hazardous substances. The risks of accidents or other events during processes involving hazardous substances (flammable, toxic, or explosive) or activities where extreme conditions are used (like high/low pressures or high/low temperatures), are subject of this research. Process safety is the absence of risk from events with these hazardous substances and activities with extreme conditions. Non-process safety or process risk is often measured by accidents, incidents and near misses and this concept will be discussed in the following sub-Section. 

Worst-case scenario. When considering the stationary source s worst-case scenario, there are selection factors to be considered. In addition to the largest inventories of a substance, the following conditions must also be considered smaller quantities handled at higher process temperatures and pressures, and proximity to the boundary of the stationary source. Sources must analyze and report additional worst-case scenarios for a hazard class if the worst-case scenario from another covered process affects a different set of public receptors than the original worst-case scenario. It is interesting to note that worst-case release data indicate that the distances and thus the populations that could be threatened are greater for toxic substances than for flammable substances. 

There are many potential causes of explosions and fires at industrial sites handling hazardous substances (a) chemical reactions that produce explosion, fire, or heat (b) ignition of explosive or flammable chemicals (c) ignition of materials due to oxygen enrichment (d) agitation of shock- or friction-sensitive compounds and (e) sudden release of materials under pressure [21,29]. 

CAUTION Methyltrichlorosilane is highly flammable and the vapor irritates eyes. It is also corrosive to the respiratory tract. Appropriate safety precautions and procedures should be adopted when handling this substance. 

Caution Carry out all procedures in a well-ventilated hood, and wear disposable vinyl and/or latex gloves and chemical-resistant goggles at all times. Keep flammable substances, especially organic solvents, from reaction vessels when handling neat diethylzinc because it ignites immediately in the air. 

Materials which may affect other materials stored in their vicinity should be handled in accordance with a written procedure. Rodenticides, insecticides, fumigating agents and sanitizing materials should not be permitted to contaminate equipment, starting materials, packaging materials, in-process materials or finished products. Toxic substances and flammable materials should be clearly marked as such and should be stored in suitably designed, separate, enclosed areas as required by national legislation. Flammable substances should be kept away from corrosive or oxidant substances at all times. 

Since air is ubiquitous, there is the risk of formation of ignitible mixtures when flammable substances are handled. For combustion to take place, the following prerequisites must be fulfilled ... 

Section 4.5 consolidates the requirements for the training of constmction woikers who handle harmful substances such as poisons, caustics, flammable liquids and gases, and other toxic substances. This section also covers the training of employees required to enter enclosed or confined spaces. 

Process safety risks Detailed study/verification is required to avoid overlooking safety risks to existing equipment/facilities. There may be more fire/explosion/toxic chemicals exposure risks during project execution as the revamp work may be executed in close proximity to existing facilities, handling flammable and toxic substances Process safety risk is relatively lower as all the equipment/ facilities are designed and installed at about the same time... 

All laboratory personnel should know the properties of chemicals they are handling as well as have a basic understanding of how these properties might be affected by the variety of conditions found in the laboratory. As stated in section 5.B, Laboratory Chemical Safety Summaries (LCSSs) or other sources of information should be consulted for further information such as vapor pressure, flash point, and explosive limit in air. The use of flammable substances is common, and their properties are also discussed in Chapter 3, section 3.D. 

Ventilation by diluting the vapors until they are no longer flammable is one of the most effective ways to prevent the formation of flammable gaseous mixtures. Use appropriate and safe exhaust whenever appreciable quantities of flammable substances are transferred from one container to another, allowed to stand in open containers, heated in open containers, or handled in any other way. In using dilution techniques, make certain that equipment (e.g., fans) used to pro... 

Acetaldehyde should be handled in the laboratory using the "basic prudent practices" described in Chapter 5.C, supplemented by the additional precautions for dealing with extremely flammable substances (Chapter 5.F). In particular, acetaldehyde should be used only in areas free of ignition sources, and quantities greater than 1 hter should be stored in tightly sealed metal containers in areas separate from oxidizers. Acetaldehyde should always be stored under an inert atmosphere of nitrogen or argon to prevent autoxidation. 

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