ATS Pulmonary Function Laboratory Manual

chapter  21

Table 21.2

Conversion Equations for Gas Volumes (1)

To Convert from

To

Multiply by

ATPS

STPD

PB − PH 2

O

× 273

273 + T

760

BTPS

PB − PH 2

O

× 310

PB − 47

273 + T

ATPD

PB − PH 2

O

PB

ATPD

STPD

PB 760

× 273

273 + T

BTPS

PB PB − 47

× 310

273 + T

ATPS

PB PB − PH 2

O

BTPS

STPD

PB − 47 760

× 273 310

ATPS

PB − 47 PB − PH 2

× 273 + T 310

O

ATPD

PB − 47 PB 760 PB − 47

× 273 + T 310

STPD

BTPS

× 310 273

ATPS

× 273 + T 273

760 PB − PH 2

O

ATPD

× 273 + T 273

760 PB

where: PB = barometric pressure (mm Hg) T = ambient temperature °C PH 2 O = ambient water vapor pressure

References 1. Intermountain Thoracic Society. Clinical pulmonary function testing, 2nd ed. Salt Lake City: Intermountain Thoracic Society; 1984.

241