Document 85wrB0xmxxbNJO4MJ6px8mOLy
252
CHAPTER 12
. 1950 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 2| per cent of the total hours of June, Juiy, 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 1950 edition of The Guide, due to the tremendous task of compiling these data, it is hoped that they will be available f<jr 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 to18 East of Mississippi River.......................... 19 to 24 Gulf Sea Shore.................12 to18 Mississippi River to Rocky Mountains___ 24 to 33 Great Lakes Shore........ 18 to 21 Rocky Mountain Area................... ............... 33 to 42 West Sea Shore..............15 to 20 West Coastal States....................................... 20 to 36
Ventilation Rate
The introduction of outside air is necessary for the ventilation of condi tioned spaces. Chapter 6 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
253
Table 3. Summer Climatic Conditions* Suggested Design Wet-Bulb?and Dry-Bulb Temperatures
Cob. 1 State
Col. 2 Station*
Col. 3
Elev ation*
Ft
Col. 4
Period or
Record*
Col. 5
Col. 6
Highest Temp. Ever
Recorded*
Design
Drt-Bglb Temp, on
TA.C. VA% Basis*
P F
Cou 7 Design
Dbt-Bulb Temp, in
Common Use* F
Ala.---------
CO 733 711
AP Ate
1893-1947
1893-1945 t9.V)liQ47
106
107 103
,00 143
1872-1947
103
...AP
219
1940-1947
104
--CO
293
1872-1947
107
AP
226
1938-1944*
103
00 6957
1899-1947
93
-AP 3473
1935-1959
107
00 1122
1895-1947
118
AP 1112
1933-1947
117
AP 2561
1935-1939
112
- 00 4853
Up to 1946
107
AP 4899
1937-1947
103
00 146
1876-1946
120
00 545
1882-1945
113
AP 463
1945-1947
107.
00 451 ,1879-1942* 110
AP 282
1942-1947
107
r.ur
Bakersfiekl-------------- AP
499
1937-1946
113
__ AP
740
1931-1947*
111
AP 192S
1935-1959
113
Eureka_____
00 132 . 1886-1947
85
CM 387
1887-1939
115
AP 281
1939-1947
111
00 -534
1877-1947
109
. AP 21 1929-1947 102
CO 303* 1877-1934
115
Red BhifT--.... - AP
346
1944-1947
112
___AP
579
1935-1939
112
116 1877-1947 114
Sacramento._______ AP
22 1938-1947 108
00 90 1871-1940 . 110
Sao Dieco--
AP 34 1939-1947 106
San Frandsoo______ CO tot 1875-1947 101
San Jose.
00 100 Up to 1946 106
AP 124
1935-1939
116
CO S39S
1871-1947 , 105
Denver Duraiuro..
AP 5379 .CO . 6558
1934-1947 Up to 1946'
104 .99
Grand Junction...... CO 4587* Up to 1946
105
00 4770
188*3-1938
104
Pueblo-................ AP 4810 1939-1947
104 .
Conn- ... HarUnrd
00
229
1905-1940*
101
Hartford
AP 20 1940-1947
98
New Haven. -
OO
180
1872-1947
101
AP 17 .1943-1947
94
D.0______ Washington_____ CO
128 .1871-1947
106
.Washington..___ AP
20 1935-1939 106
vu.
CO ` 23 19.22-1947
102-
Jacksonville
00 104
1871-1947
104
Jacksonville-- , AP
29 1938-1947 105
Key West
(X> 23 ;1871-1947 100
Key West.
AP . 48 .1939-1947
95
Miami
00 253 !1896-1947
96
Miami
AP 13 1940-1947 too
Pensacola..
CO 67 :1879-1947 103
Pensacofci.__ Tmp*
AP r 113 CO 111
-1943-1947
105
1890-1940 ! 98
Tampa
Tituavilta n
AP . AP 5
12 52
1941-1946* ; '1935-1939
98 98 102
Aupnata-
-oo
195
1871-1946
106
Aurnsta
AP 424
1939-1947
105
Mason
a) 408 !1899-1947 105
Maonn
AP f 432 :1939-1947
102
Savannah-__ Ravniimh Idaho______ Buisn.
00 115 AP 56 00 ' 2818
1871-1945* 1939-1947
1864-1939
103
105 112
Ht/ue
AP 2849
1939-1947
109
Burley....
AP 4150
1935-1939
104
Idaho Falls-- --. AP 4744 1 OO 763
1935-1939 1900-1944*
100 117
Pocatello. .
00 4522
1899-1947
105
AP : 4467* .1938-1947
103
111 106
Chiewpo
00 j 601
Up to 1946
105
Cbi**rt Mnlirw.
AP 1 615
! 1935-1939 . 107
____AP j . SM-. 1932-1947
106
. -
. . ;
__
_94
92
-- __ 99 -- 107 102 __ 95 __ --
-- 97 104 94 104
_103
80 __ -- 101
. -- __
79 . -- 103
93 __ __
95 -- 88
84
92
94
___j.
89
___ .
90 93
_
93
95 94 88
92
92 9i
95 95 . 96 . * 95
90 1 .
105 ___ 105 100 __ 110 95 ..... 95 __ 105 -- _ 90 10S __ 90 85 100
... . 100 ___, 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 Dbsign Wet-Bulb
Tbmp. in
Common Use' op
Col. 9
Average Summer
Wind Veloott*
Mph -
78 78
_ 80 . 78 __ 65
76 ... 72 70 __ 78 . 76
78 . ___
70 __ __ 65 70
70 65 70 __
72 -- 68 -- 65 70
. 64 __ 65 65 65
75 ,,
_7_S
78
80
_78
78 _ 79 -- 78-
_'
_5.4 _8.0
__
_ 6.0 __ __
_--
6.1 __ 62 . __ -- __ __ 7.9 _ 5.S __
7J9 __
10.7 __ __ 6.9 . --
6.3 - ___ __ -- 7.4 __ , 5.9 --
8.4 __
. ---8.7 __
78 7.4 . . __.
, __
76 7.9
76
78 .
78
__65
.. .
65 65
1-- .--
8.0 __ S.8
___ --
_ ___
78
_.. 75
9J .
'.76.