UA Part 8: DataAccess - B.3.3 Derived Unit Atoms

B.3.3 Derived Unit Atoms

Dimensionless units. The units ppb and ppt are deprecated because the names “billion” and “trillion” are ambiguous.

Symbol (c/s)	Display Name	Print Symbol	Kind of Quantity	Metric
10*	the number ten for arbitrary powers	10n		no
10^	the number ten for arbitrary powers	10n		no
[pi]	the number pi	π		no
%	percent	%		no
[ppth]	parts per thousand	ppth		no
[ppm]	parts per million	ppm		no
[ppb]	parts per billion	ppb		no
[pptr]	parts per trillion	pptr		no

SI units. Defined by CGPM (General Conference on Weights and Measures).

Symbol (c/s)	Display Name	Print Symbol	Kind of Quantity	Metric
mol	mole	mol	amount of substance	yes
sr	steradian	sr	solid angle	yes
Hz	hertz	Hz	frequency	yes
N	newton	N	force	yes
Pa	pascal	Pa	pressure	yes
J	joule	J	energy	yes
W	watt	W	power	yes
A	ampère	A	electric current	yes
V	volt	V	electric potential	yes
F	farad	F	electric capacitance	yes
Ohm	ohm	Ω	electric resistance	yes
S	siemens	S	electric conductance	yes
Wb	weber	Wb	magnetic flux	yes
Cel	degree Celsius	°C	temperature	yes
T	tesla	T	magnetic flux density	yes
H	henry	H	inductance	yes
lm	lumen	lm	luminous flux	yes
lx	lux	lx	illuminance	yes
Bq	becquerel	Bq	radioactivity	yes
Gy	gray	Gy	energy dose	yes
Sv	sievert	Sv	dose equivalent	yes

Other units from ISO 1000, ISO 2955, and some from ANSI X3.50.

Symbol (c/s)	Display Name	Print Symbol	Kind of Quantity	Metric
gon	gon, grade	□g	plane angle	no
deg	degree	°	plane angle	no
'	minute	'	plane angle	no
''	second	''	plane angle	no
l	liter	l	volume	yes
L	liter	L	volume	yes
ar	are	a	area	yes
min	minute	min	time	no
h	hour	h	time	no
d	day	d	time	no
a_t	tropical year	at	time	no
a_j	mean Julian year	aj	time	no
a_g	mean Gregorian year	ag	time	no
a	year	a	time	no
wk	week	wk	time	no
mo_s	synodal month	mos	time	no
mo_j	mean Julian month	moj	time	no
mo_g	mean Gregorian month	mog	time	no
mo	month	mo	time	no
t	tonne	t	mass	yes
bar	bar	bar	pressure	yes
u	unified atomic mass unit	u	mass	yes
eV	electronvolt	eV	energy	yes
AU	astronomic unit	AU	length	no
pc	parsec	pc	length	yes

Natural units. Fundamental constants of nature and units derived from these constants.

Symbol (c/s)	Display Name	Print Symbol	Kind of Quantity	Metric
[c]	velocity of light	c	velocity	yes
[h]	Planck constant	h	action	yes
[k]	Boltzmann constant	k	(unclassified)	yes
[eps_0]	permittivity of vacuum	ε 0	electric permittivity	yes
[mu_0]	permeability of vacuum	μ 0	magnetic permeability	yes
[e]	elementary charge	e	electric charge	yes
[m_e]	electron mass	m e	mass	yes
[m_p]	proton mass	m p	mass	yes
[G]	Newtonian constant of gravitation	G	(unclassified)	yes
[g]	standard acceleration of free fall	g n	acceleration	yes
atm	standard atmosphere	atm	pressure	no
[ly]	light-year	l.y.	length	yes
gf	gram-force	gf	force	yes
[lbf_av]	pound force	lbf	force	no

CGS units. The units of the older Centimeter-Gram-Second (CGS) system.

Symbol (c/s)	Display Name	Print Symbol	Kind of Quantity	Metric
Ky	Kayser	K	lineic number	yes
Gal	Gal	Gal	acceleration	yes
dyn	dyne	dyn	force	yes
erg	erg	erg	energy	yes
P	Poise	P	dynamic viscosity	yes
Bi	Biot	Bi	electric current	yes
St	Stokes	St	kinematic viscosity	yes
Mx	Maxwell	Mx	flux of magnetic induction	yes
G	Gauss	Gs, G	magnetic flux density	yes
Oe	Oersted	Oe	magnetic field intensity	yes
Gb	Gilbert	Gb	magnetic tension	yes
sb	stilb	sb	lum. intensity density	yes
Lmb	Lambert	L	brightness	yes
ph	phot	ph	illuminance	yes
Ci	Curie	Ci	radioactivity	yes
R	Roentgen	R	ion dose	yes
RAD	radiation absorbed dose	RAD	energy dose	yes
REM	radiation equivalent man	REM	dose equivalent	yes