Dust hazards

Products which decompose spontaneously, metal dust hazard... 

Wood dust hazards and precautions COSHH and the woodworking mdustnes Glue spreading machines Hardwood dust survey... 

N. Maddison, Explosion Hazards in Large Scale Purification by Metal Dust, Hazards XII—European Advances in Process Safety, Symposium Series No. 134, Institution of Chemical Engineers, Rugby, UK, 1994. 

Dust hazards ACGIH, AIHA, ANSI, BM, FIA, FM, NFPA, NSC, UL, USCG... 

The dust hazard class, Rst, vessel volume and strength, and the relieving pressure of the vent closure are the key components of the relief determination using the nomographs [27]. Although stated by Ref. [27] to be non-exact... 

The dust hazard classes for deflagrations are given in Table 7-28, with data in Tables 7-28 and 7-30A, B, C, D, and E. 

From Table 7-30C, lignite is dust hazard class 1, with = 151 bar-m/sec. 

Material Median particle size, pm Minimum explosive concentration g/m= p max bar ga (dp/dt)max> ba r/sec Ksi bar-m sec Dust Hazard Class... 

SpGr = specific gravity of fluid, relative to water =1.0 St = dust hazard class St St = stainless steel SSU = viscosity Saybolt universal seconds °S = degrees of superheat, °F T = absolute inlet or gas temperature, degrees... 

Dusts, particle sizes, 225 Dusts, hazard class, 521-523 Explosion characteristics, 524 Efficiency, centrifugal pumps, 200 Ejector control, 380 Ejector systems, 343, 344, 351 Air inleakage, table, 366, 367 Applications, 345 Calculations, 359-366 Chilled water refrigeration, 350 Comparison guide, 357, 375 Evacuation lime, 380, 381 Charts, 382 Example, 381 Features, 345... 

Limits of application Products which decompose spontaneously Toxic products and products which decompose spontaneously Products which decompose spontaneously, metal dust hazard... 

In its NEP, OSHA points out that for workplaces not covered by 1910.272, but where combustible dust hazards exist within dust control systems or other containers, citations under section 5(a)(1) of the OSH Act (the General Duty Clause) may generally be issued for deflagration (fire) or explosion hazards. National Fire Protection Association (NFPA) standards should be consulted to obtain evidence of hazard recognition and feasible abatement methods. Other standards are applicable to the combustible dust hazard. For example, if the workplace has a Class II location, then citations under 29 CFR 1910.307 may be issued to those employers having electrical equipment not meeting the standard s requirements. 

In further recognition of Industry responsibilities, efforts were made through the American Textile Manufacturers Institute to develop a set of work practices for industry-wide application to diminish the exposure of individual employees to cotton dust hazards. The comprehensive and stringent series of work practices developed were consolidated into a printed booklet in 19730). This publication was distributed widely through the industry. In addition, an industry delegation called on the Secretary of Labor, urging that the recommended practices be established immediately as a mandatory OSHA standardO). This was not done. 

In situ treatment minimizes earth removal, thereby minimizing odors, fugitive emission, and dust hazards. 

R.H. Essenhigh, Pennsylvania-StateUniv.MinerallndsExptlSta, Cite No 64, pp 1-6(1963) (An appraisal of dust explosion research) "Activities of the Instrument Society of America Subcommittee on Electrical-Dust Hazards , by T.W. Moodie, Ibid 27-32 "Proposals for Experiments on Dust Explosions by P. Lafitte R. Delbourgo, Ibid, 19-21. 

Pitch. Pitch used to be stored in solid form at the tar distillery in open bays, from which it was removed by small explosive charges. Loading of the lump pitch by mechanical shovel created a dust hazard both at the tar installation and at the customers, where the lumps had to be ground before use. In the 1990s, pitch is stored in tanks heated by superheated steam or circulating hot-oil coils and transported in liquid form in insulated rail, road tankers, or ships. When transport as a hot liquid is not feasible, not acceptable by the customer, or for small amounts, the pitch is converted into a dust-free particulate form, ie, short rods termed pencils, pastilles, or flakes. 

Chien PT. 1979. Metallic copper and silver dust hazards... [editorial]. Am Ind Hyg Assoc J 40 747-748. 

Public concern for the hazards of particle suspensions in the indoor and outdoor environment has produced regulations limiting particle concentrations and exposure levels. In the workplace, dust hazards are constrained by total mass concentration as well as concentration of specific toxic chemicals. In the ambient air, protection is stipulated in terms of total mass concentration of suspended particles andcertain chemical species, namely, lead and sulfate. Recently, measures of exposure have begun to distinguish between fine particles less than 2.5 fxm and coarse particles between 2.5 and 10 fxm. This separation relates to the ability of particles to penetrate the human respiratory system, and to different sources of fine and coarse particles. 

A great deal of frustration has arisen over the way hazardous chemicals are defined by OSHA. Most people feel more comfortable if there is a specific list of chemicals to which they can refer, but there is no such list provided under the Hazard Communication Standard. In addition, chemicals that were not previously considered hazardous because they are virtually inert or are not harmful to humans by contact with skin are now considered a dust hazard (particularly inorganic, nontoxic, noncombustible dusts that can enter the body via the respiratory system). This is where the regulation of colorants under OSHA occurs via the Hazard Communication Standard. 

Before polyacrylamides are sold, the amount of residual acrylamide is determined. In one method, the monomer is extracted from the polymer and the acrylamide content is determined by7 hplc (153). A second method is based on analysis by7 cationic exchange chromatography (154). For dry7 products the particle size distribution can be quickly determined by7 use of a shaker and a series of test sieves. Batches with small particles can present a dust hazard. The percentage of insoluble material is determined in both dry and emulsion products. 

Toxicity of DTBT is low. No evidence of carcinogenicity or gonadotoxicity Only a minor dust hazard. Acute oral (LD50) >7940 mg/kg [Rat] Acute Dermal (LD50) >7940 mg/kg [Rabbit],... 

ASBESTOS DUST HAZARD Avoid Breathing Dust Wear Assigned Protective Equipment Do Not Remain in Area Unless Your Work Requires It... 

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