Document DdDkZZ82y9JyeLoxnm2XbMLzd

168 'CHAPTER 8 1951 Guide Table 6. ApfSfIMATE ^'IHITS 0F Flammability op Single Gases and Vapobs in Aib at Qbdinaby Tempebatubes and Pbessubes* ' Gas ob Vapob Lowes Limit Pbbcent bt Volume Acetaldehyde....................................................... Acetone.......................................................... Acetylene................. ............................................ Ally!.alcohol................... ..................................... Ammonia........................................................ . Amyl aloohol....................................................... Amyl chloride.................................................. Amyitme............................................................. . Bemen (benzol)....... '.................................. Benzyl chloride.................................................. Butane......................................................... . Butyl acetate....................................................... Butyl aloohol..................................... . Butylene............................................................ Carbon disulfide................................................. Carbon monoxide............................................... Crotonaldehyde...... ........................... Cyclohexane.......... ........................................... . Cyclopropane.............................................. . -- Decane................. .............................................. Dlchloroethylene (1* 2)...................... . Diethyl selenide.................................................. Dioxane......................................... ..................... Ethane.................................................................. Ether (diethyl).................................................... ' Ethyl acetate....................................................... Ethyl alcohol........................................... ......... Ethyl bromide.................................................... Ethyl celloeolve................................................ Ethyl chloride.................................................... . Ethylene.............. ............................................... Ethylene dichloride............................................ Ethyl formate............................ ...................... Ethyl nitrite........................................................ Ethylene oxide..................... ............. ................. Furfural (126 C)...................................;........... Gasoline (variable)............................. .............. Heptane................ ............................................... Hexane................................................................. Hydrogen cyanide..................................... -- Hydrogen................... :....................................... `Hydrogen sulfide...................................,........... Illuminating gas (coal gas).............. ................. - Isobutyl aloohol...................... ........................... Isopentane........................................................... Isopropyl acetate............................................... Isopropyl alcohol............ .................... Methane-- ............. . -- .................... Methyl acetate................ ................................. Methyl alcohol....... ............................................ Methyl bromide.................................................. Methyl butyl ketone.......................................... Methyl chloride-- ..:............ ....................... Methyl cyclohexane.........I............................. Methyl ethyl ether............................................. Methyl ethyl ketone.......................................... Methyl formate.........................................--...... Methyl propyl ketone............ Natural gas (ramble).................. ................. Naphtha (benzine). t........................................ Naphthalene........................................` -- Nonane..................... .......................................... Octane........................................................'........j Paraldehyde........................................................ I Pentane......................................................... ! , 4.0 2.6 2.6 2.5 16.5 1.2 1.6 1.6 1.3 1.1 1.8 1.4 U7 2.0 1.2 12.5 2.1 1.3 2.4 0.67 9.7 2.5 2.0 3.1 1.8 2.2 3.3 6.7 2.6 4.0 2.7 ' 6.2 2.7 3.0 3.0 2.1 1.4-1.5 1.0 5.6 4.0 . 4.3 . *6.3 1.3 . 1.8 f 2.0 v5.0 > 3.1 6.7 " .13.5 1.2 8.2 ' 2.0 1.8 5.0 1.5 4.3 . 1.1 0.9 0.83 0.95 1.3 1.4 ` Uppeb Limit Pbbcent bt Volume .Closed Cup Flash Point FDeo*> 57 12.8 80 26.6 -17 70 100 6.8 . 8.4 16.0 9.7. 50 74.2 15.6 8.4 10.5 2.6 12.8 22.2 12.5 36.5 11.5 19.0 11.3 15.7 14.8 . 28.6 15.0 16.6 50 80 7.4-7.6 . 6.0 6.9 40.0 74.3 45.5 33.0 12 140 84 --22 55 1 iis 57 54 -49 28 54 104 -58 56 -31 140 25 -15 82 7.8 islo 15.5 36.5 43 53 14 62 14.5 8.0 18.7 ; io.i " ' 25 -35 9.5 30 22.7 8.2 13.5 6.d . 2^-iio . 176 2^9 88 3.2 56 7.8 \ Ait Contaminants 169 Table 6 Approximate Limits of Flammability of Single Gases and Vapobs X In Aib at Obdinaby Temperatures and Pbessubes* (Concluded) Gab ob Vapob Loweb Limit Pbbcent bt Volume . Uppeb Limit Percent bt Volume Closed Cup FlashPoint FDio6 Propylene diehlonde.............................................. Propylene oxide........................................................ Toluene (toluol)...................................................... Turpentine................................................................. y. | | | * 2.1 1.8 2.1 2.0 3.4 2.0 1.8 1.3 0.9 1.7 4.0 6.0 1.0 * 10.1 8.0 13.6 11.1 14.5 22.0 12.4 7.0 2716 21.7 70 6.0 68 59 66 "74 40 06 63 Adapted from: Fire and Explosion Hazards of Combustible Gases and Vapors, by G. W. Jones: Chapter 13, Industrial Hygiene and Toxicology, edited by F. A. Patty (Interscience Publishers, 1948); Properties of Flammable Liquids, Gases and Solids (Associated) Factory Mutual Fire Ins. Cos., January (1940)* and National Fire Codes for Flammable Liquids, Gases, Chemicals and Explosives--1046 (National Fire Protec- tion'Association). b Closed cup refers to the equipment used in flash point determinations. of air. Maximum pressures generated have been reported as high as 500 psi, although they are more likely to be of the order of 50 psi. Investiga tions on the flammable characteristics of dusts are currently made at 0.1 and 0.5 oz per cubic foot.16-51 ATMOSPHERIC POLLEN Properties of pollen grains discharged by weeds, grasses and trees and responsible for hay fever, are of special interest to designers of air cleaning equipment (see Allergic Disorders in Chapter 7, and Air Cleaning, Chap ter 33). Whole grains and fragments transported by the air range chiefly between 10 and 50 microns in size, but some have been measured as small as 5 microns, and others over 100 microns in diameter. Ragweed pollengrains are fairly uniform in size within the range of 15 to 25 microns. Pollen grains can be removed from' the air more readily than the particles of dust prevalent in outdoor air or produced by dusty processes, since the latter predominate in the range of 0.1 to 10 microns in size. Most grains are quite hygroscopic and therefore vary in weight with the humidity. Illustrations and data on individual pollen grains are available in the botanical literature.22- 2321 Geographical distribution of plants known to produce hay fever is also recorded.26-26 The quantity of pollen grains in the air is generally estimated by exposing an adhesive-coated glass plate outdoors for 24 hr, and then counting cali brated areas under the microscope. Methods are available for determin ing the number of grains in a measured volume of air,26 27 28 but their greater accuracy has not caused them to replace the more simple gravity, slide method used for most pollen counts. Counting technics vary some what, but the daily pollen counts reported in local newspapers during the hay fever season usually represent the number of grains found.on 1.8 sq, cm of a 24-hr gravity slide. Hay fever sufferers may notice the first symptoms when the pollen count; is 10 to 25, and in some localities the maximum figures'for the seasonal peak may approach 1000 for a 24-hr period, depending upon the sampling