ATS Pulmonary Function Laboratory Manual

ATS Pulmonary Function Laboratory Management & Procedure Manual | 3rd Edition

Table 21.3

International System of Units (SI)

Physical Quantity

Conventional Unit

SI Unit

Conversion Factor

Mass

pound (lb)

kilogram (kg)

0.4545 0.0254 0.09806 0.1333

Length Pressure

inch (in)

meter (m)

O

kilopascal (kPa)

cm H 2

mm Hg (Torr) pounds/in 2 (psi)

kPa kPa

6.895 9.807

Work

kilogram meter (kgm)

joule (J)

Energy

kg · m/min

J

0.1634

O

L/kPa

10.20

Compliance Resistance

L/cm H 2

O/L/sec

kPa/L/sec

0.09806

cm H 2

This appendix contains a listing of conventional and SI units for commonly used physical quantities in the pulmo- nary function laboratory. To convert a conventional unit to an SI unit, multiply the conventional unit by the conver- sion factor. To convert an SI unit to a conventional unit, divide by the conversion factor.

Table 21.4

Temperature Scales

°C

°K

°F

Description

100

373 273

212

Boiling point of water Freezing point of water

0

32

−273

0

−459

Absolute zero

242