Flameproof

Bromine is used in making fumigants, flameproofing agents, water purification compounds, dyes, medicinals, sanitizers, inorganic bromides for photography, etc. Organic bromides are also important. 

Flame emissivity Flame ionization Flameproofing cotton Flame resistance Flame-resistant fibers Flame retardancy Flame retardant... 

R. W. Litde, Flameproofing ofiTextik Fabrics, Reinhold Publishing Corp., New York, 1947. 

Organophosphorus Derivatives. Neopentyl glycol treated with pyridine and phosphorus trichloride in anhydrous dioxane yields the cycHc hydrogen phosphite, 5,5-dimethyl-l,3-dioxaphosphorinane 2-oxide (2) (32,33). Compounds of this type maybe useful as flameproofing plasticizers, stabilizers, synthetic lubricants, oil additives, pesticides, or intermediates for the preparation of other organophosphoms compounds (see Flame retardants Phosphorus compounds). 

Textile Finishing. Polyethyleneimine-A/-methylolurea derivatives improve the crease and wear resistance of cotton (429,430). The adhesion between individual wool fibers is improved by pretreatment with amines, which leads to improved shrink resistance (431). An antimicrobial finish can be appHed to cotton by using a combination of PEI and ureas to bind zinc pyrithione to the fabric (432). After wool has been provided with a flameproof finish using fluorozirconate or fluorotitanate, the wool can be neutralized with PEI (433). Conventional neutralizing agents caimot be used for this purpose since they impair the flameproof characteristics of the impregnated fabric. 

Tetrakis(hydroxymethyl)phosphoniumhydroxide, used for flameproofing ceUulosic fabrics, is manufactured in a two-step process. 

There is a maximum safe gap measured experimentally which will prevent the transmission of an explosion occurring within a container to a flammable mixture outside the container. Critical and maximum experimental safe gaps for a number of materials in air are listed in Lees (1980, pp. 491-492). These quenching effects are important in the design of flame arresters and flameproof equipment. 

Special provisions are laid down in lEC 60079-0 and lEC 60079-1 for motors required for such locations in view of fluctuating degrees of humidity and temperature. Such locations are defined with a surface temperature limit of 150°C where coal dust can form a layer, or 450°C where it is not expected to form a layer. Otherwise, other details are generally the same as for flameproof motors type Ex d , according to lEC 60079-1. For variations in length of paths, gaps, widths, creepage and clearance distances, the reader should consult these Standards. 

For hazardous areas flameproof enclosures alone are recommended, except in areas with moderate intensity of contamination and where such assemblies are located away from the affected area and in a separate well-ventilated room, when pressurized enclosures may also be. safe. The reason for this precaution is that frequent arcing takes place within the enclosure on each switching of a contactor, switch, breaker or an OCR etc. and also during operation of power and auxiliary contactors. 

Construction and verification test of flameproof enclosures of electrical apparatus 2148/1993 BS 4683-2/1993 5501-5/1997 -... 

These are heat- and flameproof cables suitable for high fire risk zones. In severe fire conditions, when the outer protection and insulation have been destroyed, these cables would still maintain continuity of essential services. 

Melamine-formaldehyde condensates are also useful in textile finishing. For example, they are useful agents for permanent glazing, rot proofing, wool shrinkage control and, in conjunction with phosphorus compounds, flameproofing. 

Introduction of non-flameproof electrical equipment into restricted area Mechanical isolation, e.g. conveyors, lifts Confined space entry Radioactive areas... 

Use of non-flameproof electrical equipment where flammable liquids/vapours/ dusts may arise... 

Removal of potentially contaminated equipment to workshop for maintenance, introduction of non-flameproof electrical equipment into a classified area. 

Provisions for primary and emergeney eommunieations (internal, e.g. with staff, emergeney personnel, and external, e.g. with die press, emergeney serviees, hospital, employees relatives, telephone links and radios) require eareful assessment. If diere is a flammable hazard on site, radios may need to be intrinsieally safe or flameproof. 

Wliere relocation is impracticable, are combustibles protected with flameproof covers or otherwise shielded ... 

Why were there so many faults Before this inspection, there had been no regular inspections. Many electricians did not understand why flameproof equipment was used and what would happen if it was badly maintained. Spare screws and screwdrivers of the special types used were not in stock, so there was no way of replacing those lost. 

Regular inspections were set up. Electricians were trained in the reasons why flameproof equipment is used, and spares were stocked. In addition, it was found that in many cases flameproof equipment was not really necessary. Division (Zone) 2 equipment—cheaper to buy and easier to maintain—could be used instead. 

Originally the classification of materials was derived from tests of proprietary explosion-proof (flameproof) enclosures. There were no published criteria. Equipment was approved relative to the lowest ignition temperature of any material in the group (Magison 1987). In about 1965 the U.S. Coast Guard asked the National Academy of Sciences (NAS) to form a panel to classify 200 materials of commerce. The Electrical Hazards Panel of the Committee on Hazardous Materials was formed by the NAS. The Panel studied many ways to estimate the hazard classification of materials. The Panel finally reported to die U.S. Coast Guard in 1970 that no workable, predicdve scheme could be defined, and it then proceeded to assign tentative classifications to the 200 materials. 

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