Document ka4g489vaMxOoogBG0LQbyb7E

516 Chapter 27 1945 Guide _______ Complied by W. G. Frank and Copyrighted. Fig. 1. Sizes and Characteristics of Air-Borne Solids Mineral particles, such as grains of sand, bits of rock, volcanic ash, or fly-ash, can be transported long distances under unusual circumstances. Thus, the dust storms of 1935 in the, Kansas district resulted in vast amounts of fine top soil being thrown high into the air. Solar.illumination as far east as Boston, was affected'noticeably and particles as large as 40 to 50 microns were, actually carried half way across the continent before they settled out. In similar manner-volcanic ash has been carried even further. It is not surprising, therefore, that fly-ash from furnace gases, cement dust and the like, can be carried for considerable distances and occasionally the engineer is confronted with the problem of removing such Air Pollution S17 "Table 1. 'Approximate Limits-of- Inflammability- of.-Single- Gases and Vapors in Air at Ordinary Temperatures and Pressures3 Gas or Vapor Lower Loot TTtittttb Tnrrr Volume ns Volume In Pia Cert Feb Cent Gas ob Vapor Lower Limit Siqbsb Limit Volume in Volume in Per Cent Per Cent Acetone.______________ Acetylene------ :-----------Acetyleneb.------------------ Ammonia-____________ Amyl alcohoL--------- :-- Amyl chloride.___ _____ Amylene______________ Benzene.______________ Benzine.____ __________ Blast-furnace gas._____ Butane________________ Butyl acetate (30 C)__ Butyl alcoKol___ Carbon disulphide____ Carbon monoxide.____ Croton aldehyde.___... Cyclohexane................. Cyclopropane.________ Decane_______________ Dichlorethylene.__ ___ Diethyl selenide.___ Dioxan________________ Ethane_______________ Ethyl alcohol_________ Ethyl bromide________ Ethylene dichloride___ Ethylene. _ _____ . Ethyl ether___________ Ethyl formate._______ Ethyl nitrite Ethylene oxide.____ __ Furfural (125 C)______ Gasoline_____________ Heptane_____________ 4.0 3.0 2.5 2.5 2.3 2.4 16.0 1.2 1.4 1.6 . 1.4 1.1 35.0 1.9 1.7 1.7 1.7 1.2 12.5 2.1 1.3 2.4 0.7 9.7 2.5 2.0 3.2 2.0 3.3 6.7 4.0 6.2 3.0 1.8 2.7 3.0 3.0 2.1 1.4 1.0 57.0 13.0 8_0_.0 27.0 __ _ 6.7' ' 74.6 8.4 7.6 ____ 9.0 50.0 74.0 15.5 8.3 10.3 12.8 22.0 12.5 11.5 19.0 11.2 14.8 15.9 29.0 36.5 16.5 80.0 6.5 Hydrocyanic acid___ Hydrogen sulphide___ Illuminating gas._____ Iso-butane._................ Iso-butyl alcohol____ Iso-pentane__________ Iso-propyl acetate___ Iso-propyl alcohol Methane-------------------Methane^____________ Methyl acetate. ____ Methyl alcohol............ Methyl bromide______ Methyl chloride______ Methyl cyclohexane__ Methyl ethyl ether.__ Methyl ethyl ketone.. Methyl formate._____ Methyl'propyl ketone Natural gas._ Nonane____ __________ Octane............................ O-Xylene_____________ Pentane______ . Propane._____________ Propyl alcohoL Propylene................ Propylene dichloride.. Propylene oxide....... Toluene--------------------Vinyl ether. ........... Vinyl chloride__ ___ Water gas 1.2 5.6 4.1 4.3 5.3 1.2 1.8 1.8 1.3 1.8 2.6 : 5.3 5.0 3.1 6.7 13.5 1.2 8.0 1.2 2.0 1.8 5.0 1.5 4.8 0.8 0.9 1.0 . 1.3 1.4 2.4 1.8 2.5 2.0 3.4 2.1 1.8 1.3 1.7 4.0 6 to 9 6.9 40.0 74.0 45.5 31.0 8.4 7.8 14.6 15.0 15.5 36.0 14.5 8.0 19.0 _ 10.1 10.0 23.0 8.5 13.5 6.0 , 7.8 9.5 8.0 11.1 14.5 21.5 12.4 6.7 27.0 22.0 55 to 70 .Limits of Inflammability of Gases and Vapors, by H. F. Coward and G. W. Jones (Cl. 5. Bureau af Mines, Bulletin No. 279. 1939). ^Turbulent mixture. material before the air in question is suitable for use in building venti lation. The physical properties of the particulate impurities of air are.summar ized conveniently in the chart of Fig. 1. In the case of gases, the objectionable features are physiological effects, inflammability (see Table 1) and odors. Dust Concentrations It is customary to report dust concentrations as grains per 1000 cu ft or milligrams per cubic meter (except for dusts that may cause pneu moconiosis, which are reported as so many particles per cubic foot of air). Gas concentrations.are commonly recorded as milligrams per cubic meter