Environment Flammability

Electrical hardware should be Underwriter s Laboratory (i.e., UL) listed for the environment, flammable gas, dust, or flyings. 

Health and Safety. Petroleum and oxygenate formulas are either flammable or combustible. Flammables must be used in facUities that meet requirements for ha2ardous locations. Soak tanks and other equipment used in the removing process must meet Occupational Safety and Health Administration (OSHA) standards for use with flammable Hquids. Adequate ventilation that meets the exposure level for the major ingredient must be attained. The work environment can be monitored by active air sampling and analysis of charcoal tubes. 

C. F. Key, J. G. Austin, and J. W. Bransford, Flammability of Materials in Gaseous Ouygen Environments, NASA TMX-64783, National Aeronautics and Space Administration, Washiagton, D.C., Sept. 1973. 

Udel is a slightly yellow but tianspaient engineering thermoplastic. It has low flammability and smoke emission and good electrical properties. It has excellent resistance to water, steam, and alkaline solutions. Specific uses for Udel iaclude microwave cookware, beverage dispensers, coffee brewers, cookware, hair dryers, com poppers, and steam table trays. Its steam resistance makes it particularly fit for a dishwasher environment. Properties of polysulfone resias ate given ia Table 11. 

Ethyl alcohol is a flammable Hquid requiring a red label by the DOT and Coast Guard shipping classifications its flash point is 14°C (Tag, closed cup). Vapor concentrations between 3.3 and 19.0% by volume in air are explosive. Liquid ethyl alcohol can react vigorously with oxidi2ing materials. Ethyl alcohol has found wide appHcation in industry, and experience shows that it is not a serious industrial poison (273—275). If proper ventilation of the work environment is maintained, there is Httle likelihood that inhalation of the vapor will be ha2ardous. 

The test shall be hydrostatic, using water, with the following exceptions. If there is a possibility of damage due to freezing or if the operating fluid or piping material would be adversely affected by water, any other suitable hquid may be used. If a flammable hquid is used, its flash point shall not be less than 50°C (120°F), and consideration shall be given to the test environment. 

In most chemical areas, grounded persons can wear any type of clothing safely. For the unusually sensitive environments hsted above, antistatic or conductive clothing shoiild be worn, and persons must be grounded. Removal of outer garments in a flammable location can cause hazardous discharges and should be avoided (NFPA 77, Static electricity, para. 2-2, 1993). 

Consequence Phase 3 Develop Detailed Quantitative Estimate of the impacts of the Accident Scenarios. Sometimes an accident scenario is not understood enough to make risk-based decisions without having a more quantitative estimation of the effects. Quantitative consequence analysis will vary according to the hazards of interest (e.g., toxic, flammable, or reactive materials), specific accident scenarios (e.g., releases, runaway reactions, fires, or explosions), and consequence type of interest (e.g., onsite impacts, offsite impacts, environmental releases). The general technique is to model release rates/quantities, dispersion of released materials, fires, and explosions, and then estimate the effects of these events on employees, the public, the facility, neighboring facilities, and the environment. 

Of the instmments described only some are suitable for use outside the laboratory. Where any instrument is carried into a flammable environment it should either be certified as intrinsically safe for exposure to the flammable atmosphere or isolated from the atmosphere such as by keeping it within a purged enclosure. Any probe connected to the instmment must be separately considered as a possible ignition source. Electrometers are described in [ 1531. A more general review of electrostatic instruments is given in [ 136]. 

Vertical Pressure Leaf Filters are essentially the same as Horizontal Plate Filters except for the orientation of the filter elements which are vertical rather than horizontal. They are applied for the polishing slurries with very lov solids content of 1-5% or for cake filtration with a solids concentration of 20-25%. As with the horizontal plate filter the vertical leaf filters are also well suited for handling flammable, toxic and corrosive materials since they are autoclaved and designed for hazardous environments when high pressure and safe operation are required. Likewise, they may be readily jacketed for applications whenever hot or cold temperatures are to be preserved.The largest leaf filters in horizontal vessels have a filtration area of 300 m and vertical vessels 100 m both designed for an operating pressure of 6 bar. 

Nutsche filters are well suited for handling flammable, toxic, corrosive and odor-noxious materials since they are autoclaved and designed for use in hazardous and ex-proof environments when extremely safe operation is required. They are available in almost any size with the larger machines for a slurry filling batch of 25 m and a cake volume of 10 m Such filters have a filtration area of 15 m and are suitable for fast filtering slurries that produce readily 0.5 m thick cakes. The basic configuration is shown in Figure 11. 

Hazardous chemicals is a broad categoiy that includes chemicals that may be toxic, flammable, corrosive, explosive, or luirmful to tlie environment. A toxic chemical is one type of a hazardous chemical. Toxic chemicals cause adverse health effects, such as severe illness or deatli, when ingested, inltaled, or absorbed by a lii ing organism. 

Each situation must be evaluated on its own merits or conditions and operating situation, and even its environment with respect to the plant flammable processing equipment. 

MITI is currently undergoing research to develop technology for the recycling of non-flammable plastics such as those used in business machines and computers. Their National Institute for Resources and Environment plans to decompose, without the production of harmful substances, non-flammable polymers by means of liquid phase hydrocracking, and to recover from them light oils such as benzene, toluene and xylene. The key to the technology, it is claimed, lies in the development of a catalyst which will be able to combine hazardous substances such as bromine and chlorine contained in the waste plastics. 

EXTREMELY FLAMMABLE (Where the substance or preparation falls within the definition given in Notes 3c) 9. DANGEROUS FOR THE ENVIRONMENT in combination with risk phrases 10 50... 

Risk analysis. The risk of accidents can be assessed in terms of two factors severity and probability of the accident. Severity is high if consequences of the accident to employees, the public, the environment, and the plant are significant. Severity is related to the amount and properties of hazardous (toxic, flammable, explosive) substances that can escape to the surroundings during the accident, and to the energy that is released during the accident. Probability is associated with the likelihood of the occurrence of unwanted chains of events and the time of development of undesired events starting from the disturbance. If the time... 

The death knell for pneumatic control equipment has been predicted for at least the past 15 years. So far this has not happened, but it is still predicted. The major reason why pneumatic equipment is so popular is that the pneumatic control valve is cheap and requires little maintenance. The pneumatic system also has the advantage of posing no problems in the presence of flammable substances. (Extreme care must be exercised if electrical signals are used in such environments.) One major problem with pneumatic systems is the delay encountered in sending a pneumatic signal over 300 ft (90 m). However, this can usually be avoided by mounting the controller next to the unit instead of in the control room. This does not affect the monitoring of the process, which can still be done in a remote location. 

Allied to flammability is smoke density suppression especially in confined spaces, e.g., airliners, houses, warehouses. Many aromatic compounds bum with a smoky flame (e.g., styrene), whereas corresponding aliphatic compounds tend to burn with a clean "transparent" flame. This is because air-bome poly-aromatic vapours decompose to give volatile carbon (smoke) in low oxygen environments. 

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