30 40 50 60 70 80 90 100 110 115DRY BULB TEMPERATURE - F

10 15 20 25

30

35

40

45

50

55

ENTH

ALPY

- Bt

u pe

r lb.

of d

ry a

ir an

d as

socia

ted

moi

stur

e

ENTHALPY - Btu per lb. of dry air and associated moisture

10

15

20

25

30

35

40

45

50

55

ENTH

ALPY

- Btu

per lb

. of d

ry air

and a

ssoc

iated

mois

ture

WET

BUL

B TE

MPER

ATUR

E -

F

0

10

20

30

40

50

60

70

80

90

100

110

120

130

140

150

160

170

180

190

200

HUM

IDIT

Y RA

TIO

(or S

pecif

ic Hu

mid

ity) G

RAIN

S O

F M

OIS

TURE

PER

PO

UND

OF

DRY

AIR

0.05

0.10

0.15

0.20

0.25

0.30

0.35

0.40

0.45

0.50

0.55

0.60

0.65

0.70

0.75

0.80

0.85

0.90

0.95

1.00

1.05

1.10

1.15

1.20

1.25

1.30

VAPO

R PR

ESSU

RE -

INCH

ES O

F M

ERCU

RY

0 10

20 25

30

35

40

45

50

55

60

65

70

75

80

85

DEW

PO

INT

TEM

PERA

TURE

- F

Chart by: HANDS DOWN SOFTWARE, www.handsdownsoftware.com

STANDARD AIR

1.000.95

0.90

0.85

0.80

0.75

0.70

0.65

0.60

0.55

0.50

0.45

0.40

0.35

0.300.250.20SENSIBLE HEAT RATIO = Qs / Qt

SE

NS

IBLE

HE

AT

RA

TIO

= Q

s / Q

t

10% RELATIVE HUMIDI

TY

20%

30%

40%

50%

60%

70%80

%90

%

WET BULB TEMPERATURE - F

20

25

3032

35

40

45

50

55

60

65

70

75

80

85

90

12.6

12.8

13.0

13.2

13.4

13.6

13.8

14.0

14.2

14.4

14.6

14.8

15.0

Return Air

Outside Air

Mixed Air

Discharge Air

Return Air

BAROMETRIC PRESSURE: 29.921 in. HG

Chart by: HANDS DOWN SOFTWARE, www.handsdownsoftware.com