APPENDIX II

UNITS OF MEASURE AND CONVERSION FACTORS

Metric equivalents
Length:
1 cm = 0.3937 in	1 in = 2.540 cm
1 m = 3.281 ft	1 ft = 0.3048 m
1 m = 1.094 yd	1 yd = 0.9144 m
1 km = 0.621 mile	1 mile = 1.609 km
1 yd = 3 ft = 36 in	1 mile = 1760 yd = 5280 ft
Area:
1 cm2 = 0.155 in2	1 in2 = 6.452 cm2
1 m2 = 10.76 ft2	1 ft2 = 0.0929 m2
1 m2 = 1.19599 yd2	1 yd2 = 0.83613 m2
1 km2 = 0.3861 mile2	1 mile2 = 2.59 km2
1 ha = 0.003861 mile2	1 mile2 = 259 ha
1 ha = 2.471 acre	1 acre = 0.4047 ha
1 km2 = 100 ha	1 mile2 = 640 acres
Volume:
1 cm3 = 0.061 in3	1 in3 = 16.39 cm3
1 m3 = 35.31 ft3	1 ft3 = 0.02832 m3
1 litre = 61 in3	1 in3 = 0.01639 litre
1 litre = 0.2642 US gal	1 US gal = 3.785 litre
1 litre = 0.2200 Imp gal	1 Imp gal = 4.546 litre
1 litre = 1000 cm3	1 gas = 4 quarts
Mass:
1 kg = 2.205 lb	1 lb = 0.4536 kg
1 tonne = 1.102 US ton	1 US ton = 0.9072 tonne
1 tonne = 0.9842 Imp ton	1 Imp ton = 1.016 tonne
1 tonne = 19.684 cwt	1 cwt = 0.0508 tonne
Pressure:
1 kg/m2 = 0.2048 lb/ft2	1 lb/ft2 = 4.882 kg/m2
1 gm/cm2 = 0.0142 lb/in2	1 lb/in2 = 70.31 gm/cm2
	1 atmos = 1.033 kg/cm2
Density:
1 kg/m3 = 0.06243 lb/ft3	1 lb/ft3 = 16.02 kg/m3

Source: (39)

Forest products measures

Product and unit		Solid volume
		(m3)	(ft3)	(1000)	(Standard)
				(board feet)	(Petrograd)
Roundwood:
	1 Hoppus ft3	0.03605	1.273
	1 ton of 50 hoppus ft3	1.8027	63.66
	1 cunit	2.8316	100.0
	1 cord 1/	3.625	128.0
	1 stere 1/	1.0	35.315
	1 fathom 1/	6.1164	216.0
Sawnwood:
	m3	1.0	35.31	0.424	0.214
	Standard (Petrograd)	4.672	165.0	1.98	1.0
	ft3	0.02832	1.0	0.012	0.00606
	1000 board feet (1000 super feet)	2.36	83.33	1.0	0.505
	Ton of 50 ft3	1.416	50.0	0.600	0.303
Plywood:
	1 Tonne	1.54	54.3
	1000 m2 (1 mm thick)	1.0	35.31	0.4238
	1000 ft2 (1/8 in thick)	0.295	10.42	0.125
		(m3)	(ft3)	(Tonne)	(1000 lbs)
Particleboard:
	m3	1	35.31	0.650	1.433
	1000 m2 (1 mm thick)	1	35.31	0.650	1.433
	1000 ft2 (1/8 in thick)	0.295	10.42	0.192	0.423

^1/ Stacked volume
Source: (39)

Energy conversion factors
Energy, work, heat:
1 J = 0.239 cal	1 cal = 4.187 J
1 J = 0.738 ft lb f	1 kcal = 3.968 Btu
1 J = 107 ergs	1 Btu = 1.055 kJ
1 kJ = 0.948 Btu	1 Btu = 0.293 Wh
1 MJ = 0.0095 therm	1 therm = 105 Btu
1 MJ = 0.3725 hp hour	1 therm = 105.5 MJ
1 MJ = 0.278 kWh	1 therm = 29.31 kWh
1 kWh = 3.60 MJ	1 ft lb f = 1.356 J
1 kWh = 0.0559 hp day	1 hp hour = 2545 Btu
1 kWh = 3413 Btu	1 hp hour = 2.685 MJ
1 kWh = 860 kcal	1 hp day = 17.88 kWh
Power, heat flow rate:
1 W = 0.86 kcal/h	1 Btu/h = 0.293 W
1 W = 44.25 ft lb f/min	1 kcal/h = 1.163 W
1 kW = 3412 Btu/h	1 hp = 0.746 kW
1 kW = 1.341 hp	1 hp = 42.42 Btu/min
1 kW = 56.87 Btu/min	1 hp = 33000 ft lb f/min
Calorific value, heat content:
1 MJ/kg = 238.8 kcal/kg	1 Btu/lb = 0.5556 cal/gm
1 MJ/kg = 430 Btu/lb	1 Btu/lb = 2.326 kJ/kg
1 MJ/m3 = 26.84 Btu/ft3	1 Btu/ft3 = 37.26 kJ/m3
1 cal/gm = 4.187 kJ/kg	1 Btu/Imp gal = 232.1 kJ/m3
1 Kcal/kg = 1.80 Btu/lb	1 Btu/US gal = 278.7 kJ/m3
Heat flux:
1 W/m2 = 0.317 Btu/ft2h	1 Btu/ft2h = 3.155 W/m2
1 kW/m2 = 860 kcal/m2h	1 Btu/ft2h = 2.713 kcal/m2h
	1 kcal/m2h = 1.163 W/m2
Heat transfer coefficient:
1 W/m2 °C = 0.176 Btu/ft2h °F	1 Btu/ft2h °F = 5.678 W/m2 °C
1 W/m2 °C = 0.86 kcal/m2h °C	1 kcal/m2h °C = 1.163 W/m2 °C
Thermal conductivity:
1 W/m °C = 0.578 Btu/ft h °F	1 Btu/ft2h °F = 1.73 W/m °C
1 W/m °C = 6.93 Btu in/ft2h °F	1 Btu in/ft2h °F = 0.144 W/m °C
Specific heat capacity:
1 kJ/kg °C = 0.239 Btu/lb °F	1 Btu/lb °F = 4.187 kJ/kg °C
1 kJ/m3 °C = 0.0149 Btu/ft3 °F	1 Btu/ft3 °F = 67.07 kJ/m3 °C

Source: (78)

Temperature:
°C = (°F - 32)	°C = 1.8 °C + 32

Three units of energy are currently in use in industry, the therm, joule and kilowatt hour. Throughout this document the SI unit of energy, the joule, has been used and due to its being a comparatively small unit of measure, large quantities are expressed as multiples by the addition of a prefix:

K kilo (x 10³)
M mega (x 10⁶)
G giga (x 10⁹)
T tera (x 10¹²)
P peta (x 10¹⁵)

e.g. MG = megajoule = J x 10⁶, GJ - gigajoule J x 10⁹.

Conversion factors used to obtain a common unit of energy

	Btu	Joule	Kilowatt hour	Therm
		(J)	(kWh)
Btu	1	1.055x103	0.2931x10-3	10x10-6
Joule	0.948x10-3	1	0.2778x10-6	9.48x10-9
Kilowatt hour	3.412x103	3.6x106	1	34.12x10-3
Therm	100x103	105.5x106	29.31	1

Moisture content:

Moisture content may be expressed in two ways, either on a dry weight basis or green weight (wet) basis.

The dry weight basis is preferred in the forestry and mechanical forest products industry:

Moisture content % =

whereas the wet basis is favoured in the pulp and paper industry and by those using wood as a fuel, as the water content may be related directly to its heat value.

Moisture content % =