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BUSBuilding Understanding Standard

Vocabularies / Units

Unit codes

77 codes an engineer can read without consulting an external registry. Normative when unitSystem is bus, which is the default.

77 codes

angle 2

Code	Meaning	UCUM (informative)
`deg`	degree of arc	deg
`rad`	radian	rad

apparentPower 1

Code	Meaning	UCUM (informative)
`kVA`	kilovolt-ampere	kV.A

area 2

Code	Meaning	UCUM (informative)
`ft2`	square feet	[sft_i]
`m2`	square meters	m2

concentration 4

Code	Meaning	UCUM (informative)
`mg/m3`	milligrams per cubic meter	mg/m3
`ppb`	parts per billion	[ppb]
`ppm`	parts per million	[ppm]
`ug/m3`	micrograms per cubic meter	ug/m3

count 1

Code	Meaning	UCUM (informative)
`count`	count	1

electricCurrent 1

Code	Meaning	UCUM (informative)
`A`	ampere	A

electricPotential 1

Code	Meaning	UCUM (informative)
`V`	volt	V

energy 8

Code	Meaning	UCUM (informative)
`Btu`	British thermal unit	[Btu_IT]
`J`	joule	J
`MJ`	megajoule	MJ
`MWh`	megawatt hour	MW.h
`Wh`	watt hour	W.h
`kWh`	kilowatt hour	kW.h
`therm`	therm	[Btu_IT]
`tonHours`	ton hours of refrigeration	—

frequency 1

Code	Meaning	UCUM (informative)
`Hz`	hertz	Hz

humidityRatio 2

Code	Meaning	UCUM (informative)
`gPerKg`	grams of water per kilogram of dry air	g/kg
`grPerLb`	grains of water per pound of dry air	[gr]/[lb_av]

illuminance 2

Code	Meaning	UCUM (informative)
`fc`	foot-candle	[ftc]
`lux`	lux	lx

length 4

Code	Meaning	UCUM (informative)
`ft`	foot	[ft_i]
`in`	inch	[in_i]
`m`	meter	m
`mm`	millimeter	mm

mass 2

Code	Meaning	UCUM (informative)
`kg`	kilogram	kg
`lb`	pound	[lb_av]

massFlow 2

Code	Meaning	UCUM (informative)
`kg/s`	kilograms per second	kg/s
`lb/h`	pounds per hour	[lb_av]/h

power 7

Code	Meaning	UCUM (informative)
`Btu/h`	BTU per hour	[Btu_IT]/h
`MBtu/h`	thousand BTU per hour	k[Btu_IT]/h
`MW`	megawatt	MW
`W`	watt	W
`hp`	horsepower	[HP]
`kW`	kilowatt	kW
`tonRef`	tons of refrigeration	—

pressure 6

Code	Meaning	UCUM (informative)
`Pa`	pascal	Pa
`bar`	bar	bar
`inH2O`	inches of water column	[in_i'H2O]
`inHg`	inches of mercury	[in_i'Hg]
`kPa`	kilopascal	kPa
`psi`	pounds per square inch	[psi]

ratio 3

Code	Meaning	UCUM (informative)
`pct`	percent	%
`pf`	power factor	1
`ratio`	dimensionless ratio	1

reactivePower 1

Code	Meaning	UCUM (informative)
`kVAR`	kilovolt-ampere reactive	—

relativeHumidity 1

Code	Meaning	UCUM (informative)
`pctRH`	percent relative humidity	%

resistance 1

Code	Meaning	UCUM (informative)
`ohm`	ohm	Ohm

rotationalSpeed 1

Code	Meaning	UCUM (informative)
`rpm`	revolutions per minute	{rpm}

soundLevel 2

Code	Meaning	UCUM (informative)
`dB`	decibel	dB
`dBA`	A-weighted decibel	—

temperature 3

Code	Meaning	UCUM (informative)
`K`	kelvin	K
`degC`	degrees Celsius	Cel
`degF`	degrees Fahrenheit	[degF]

temperatureDifference 2

Code	Meaning	UCUM (informative)
`deltaDegC`	delta degrees Celsius	Cel
`deltaDegF`	delta degrees Fahrenheit	[degF]

time 6

Code	Meaning	UCUM (informative)
`day`	day	d
`h`	hour	h
`min`	minute	min
`ms`	millisecond	ms
`s`	second	s
`yr`	year	a

velocity 2

Code	Meaning	UCUM (informative)
`fpm`	feet per minute	[ft_i]/min
`m/s`	meters per second	m/s

volume 4

Code	Meaning	UCUM (informative)
`L`	liter	L
`ft3`	cubic feet	[cft_i]
`gal`	US gallon	[gal_us]
`m3`	cubic meters	m3

volumetricFlow 5

Code	Meaning	UCUM (informative)
`L/s`	liters per second	L/s
`cfm`	cubic feet per minute	[cft_i]/min
`gpm`	US gallons per minute	[gal_us]/min
`m3/h`	cubic meters per hour	m3/h
`m3/s`	cubic meters per second	m3/s

Machine-readable: bus-units.json