Document YGOgVDjvMODRg1Md20EBjjaVN

274 CHAPTER 15 1949 Guide States. The highest temperature ever recorded is for the period of record shown. In some cases it should be noted that this period of record is com paratively short and higher temperatures may be expected. In making comparisons for other localities than those shown in Table 3 due considera tion must be given to elevation. Column 6 of Table 3 indicates the design dry-bulb temperature suggested by the A.S.H.V.E. Technical Advisory Committee on Weather Design Conditions. This temperature is the maximum hourly outdoor tempera ture which has been equalled or exceeded 2j per cent of the total hours of June, July, August and September for the period of record, in this case the 5 year period 1935-1939, and should not be confused with the period of record given in Column 4 which applies only to highest temperature ever recorded. Since all of these data (Column 4) are based on airport records they are not necessarily applicable to cities. The data given in Columns 7 and 8 were obtained from local A.S.H.V.E. Chapter Secretaries and represent the design temperatures in local use. Where such information was not available it was taken from a publication of the A.C.R.M.A.1 and from various other sources. The Technical Advisory Committee on Weather Design Conditions has suggested that wet-bulb design temperature be taken as that wet-bulb temperature which has been equalled or exceeded 5 per cent of the hours during months of the period of record. While not available for the 1949 edition of The Guide due to the tremendous task of compiling these data it is hoped that they will be available for some stations for future editions. The wind velocity to be used in design should be that wind velocity which accompanies the design temperatures in each instance but since these data are not available the average summer wind velocities for the period of record were taken from U. S. Weather Bureau records revised to 1948. It is pointed out that this is not necessarily the velocity which coincides with the design temperatures but it may serve as a guide to the designer. Other weather data such as daily range of temperature are useful particu larly when making cooling load calculations for an early morning peak on an east exposure. Daily range of temperature is the difference between the average of the daily maximum dry-bulb temperatures and the aver age of the daily minimum temperatures. This range is highest in semiarid or desert regions and at high elevations and lowest near the oceans or very large lakes. The daily range of temperature (Fahrenheit de grees) in July for the principal areas of the United States can be ap proximated from the following tabulation: East Sea Shore.............12 to 18 Gulf Sea Shore............. 12 to 18 Great Lakes Shore.......18 to 21 West Sea Shore.............15 to 20 East of Mississippi River...........................19 to 24 Mississippi River to Rocky Mountains___24 to 33 Rocky Mountain Area.................................. 33 to 42 West Coastal States...................................... 20 to 36 Ventilation Rate The introduction of outside air is necessary for the ventilation of condi tioned spaces. Chapter 12 suggests minimum outdoor-air requirements for representative applications; but it is to be emphasized that minimum re quirements are not necessarily adequate requirements for all psychological attitudes and physiological responses. Local codes and ordinances frequently specify ventilation requirements for public places and for industrial installations. Recommended and minimum ventilation rates for the most common Cooling Load 275 Table 3. Summeb Climatic Conditions* Suggested Design Wet-BuU>2and Dry-Bulb Temperatures Cou 1 Stats Cou2 Station** -----------Ab--- CO CO CO Montgomery ___ AP CO .... AP . CO AP CO .._.AP Winslow. . AP CO AP CO CO AP CO AP Bakersfield AP AP Daggett......... .. AP CO ,,CO AP _ CO Oakland............... ,,.AP CO Red Bluff_____ -____AI ____AP CO Sacramento.......... AP CO AP San Francisco________CO San Jose.-............ CO Williams--_______ AP CO Denver ___ AP Durango............. --CO Grand Junction ___a> Pueblo Pueblo CO AP CO Hartford.......... - AP New Haven-_____ CO New Haven- AP D.C_______ Washington-- CO .Washington._____ AP Fb Apalachicola_________GO !a*lr0nmnlio *' CO AP Key West............ Key West.... Mi*i riv CO AP CO PatinMile .. AP CO AP Tampa Tamm GO AP Titusville_______ AP Ga_______ ___ AP AiigiLita,.............. -CO AP Macon .... CO Macon___L'____ . AP Idaho______ Bnisn ni.... Rnrtw - CO .AP CO AP AP AP luowhttnn . - CO Pocatello............. CO .. AP CO fThu*n ,, AP Moline^............ AP Cob. 3 Elev ation0 Ft Cob. 4 Period ov Record*1 Cob.5 Col 6 Highest Temp. Ever' Recorded^ Design Dby>Bulb Temp, on TA.C. 2H% Basts* F F Col 7 Design Dry-Bulb Temp, in Common Use> F 733 71! 615 143 219 293 226 69S7 3473 1122 1112 2561 4653 4899 146 545 463 451 282 499 740 1925 132 387. 281 534 21 305 346 579 116 22 90 34 164 100 124 5379 6558 4587* 4770 4810 229 20 180 17 128 20 23 104 29 23 48 253 13 67 113 111 12 52 1020 195 424 403 432 US 56 2818 2849 4150 .4744 763 4522 4467 60! 615 594 1893-1947 1893-1945 1939-1947 1872-1947 1940-1947 1872-1947 1938-19444 1899-1947 193S-1939 1895-1947 1933-1947 1935-1939 Up to 1946 1937-1947 1876-1946 1882-1945 1945-1947 ,1879-19424 1942-1947 1937-1946 1931-19474 1935-1939 1886-1947 4887-1939 1939-1947 1877-1947 1929-1947 - .1877-1934 1944-1947 1935-1939 1877-1947 1938-1947 1871-1940 1931M947 1875-1947 Up to 1946 1935-1939 1871-1947 1934-1947 Up to 1946' Up to 1946 1889-1938 1939-1947 1905-19404 1940-1947 1872-t947 1943-1947 1871-1947 1935-1939 1922-1947 1871-1947 1938-1947 1871-1947 1939-1947 1896-1947 1940-1947 1879-1947 1943-1947 1890-1940 1941-19464 1935-1939 1935-1939 1871-1946 1939-1947 1899-1947 1939-1947 lS711945d 1939-1947 1864-1939 1939-1947 1935-1939 1935-1939 1900-19444 1899-1947 1938-1947 1872-1947 Up to 1946 1935-1939 1932-1947 105 107 103 103 104 107 103 93 107 . 118 117 112 107 103 120 113 107 110 107 113 111 113 85 115 111 109 102 115 112 112 114 108 110 106 101 106 116 105 104 .99 105 104 104 101 98 101 94 106 106 102 104 105 100 95 96 100 103 . . 105 98 98 98 102 106 105 105 102 105 105 112 109 104 100 117 105 103 106 105 107 106 . ___ 94 . __ 92 -- ___ 99 -. 107 102 __ 95 . ___ ___ __ 97 104 94 104 __ 103 ___ 80 ...... _ 101 -- -- , 79 .. ,, ___ 103 93 -- ___ ___ 95 88 , 84 __ 92 __ ___ 94 , 89 _ __ ___ 90 95 ___ __ 93 .. 95 94 88 __ .. . 92 . 92 94. 95 95 __ 95 __ 95 __ 90 . __ 105 __ 105 100 110 95 . 95 105 _ .r __ 90 _105 _. 90 85 100 ,,__ too ___ 85 85 91 95 95 95 95 93 95 __ 95 .... 95 95 -- 98 91 ,, , 95 -- 95 , 95 98 95 _95 95 ___ __ "95 95 __ 98 _95 96 Col 8 Design Wet-Bulb Temp, in Common Use1 F 78 78 __ 80 78 -- 65 -- 76 . 72 70 _78 76 ^_ 78 __ _70 __ 65 70 70 65 70 -- .. 72 __ 63 __. 65 70 -. 64 .. 65 65 65 --. 75 __ . _75 78 ___ ' 80 78 , 78 __ 79 . 78 .. . 78 __ -76 76 __ _78 78 _ 65 ___ _._. 65 65 ___ 78 7S -- 76 Cou9 Average Summer Wind VELocrm Mfb __ 5.4 __ 8,0 _/ ___ ___ __ __ 6.0 . __ -- 6.1 __ 6.2 -__ -- _ ___ 7.9 -- 5.8 -- _ 7.9 - 10.7 ___ ___ 6.9 ___ __ 6.3 -----. __ ___ -- 5.9 .___ -- -- ___ _ 8.7 __ 7.4 -- 7.9 -- -- -- 8.0 ___ 5.8 .-- -- . 9.5 -- X