This Annex provides an excerpt from the UCUM Specification available at https://ucum.org.
The Unified Code for Units of Measure (UCUM), also known as the “UCUM Specification”, is copyright ©1999-2021, Regenstrief Institute, Inc. All rights reserved.
The UCUM license is available in https://ucum.org/license. This license includes a disclaimer of warranties.
UCUM can represent any number of valid units derived from 7 basic units. To that end, the standard combines various components:
- Basic units
metre (m, length)
second (s, time)
gram (g, mass)
radian (rad, angle)
Kelvin (K, temperature)
Coulomb (C, electric charge)
candela (cd, luminous intensity)
- derived units with conversion factors and formulas for the reduction to base units
- prefixes, i.e. a list of 30 standard prefixes to generate multiples (e.g. k for kilo, multiplier 10³) or fractions (e.g. d for deci, multiplier 10-1) of measurement units
- symbols and operators as well as syntax rules for their combination as follows:
|
<sign > |
::= |
“+” | “-” |
|
<digit > |
::= |
“0” | “1” | “2” | “3” | “4” | “5” | “6” | “7” | “8” | “9” |
|
<digits > |
::= |
|
|
<factor > |
::= |
<digits > |
|
<exponent > |
::= |
|
|
<simple-unit > |
::= |
<ATOM-SYMBOL > | <PREFIX-SYMBOL ><ATOM-SYMBOL[metric] > |
|
<annotatable > |
::= |
<simple-unit ><exponent > | <simple-unit > |
|
<component > |
::= |
<annotatable ><annotation >| <annotatable >| <annotation >| <factor >| “(”<term >“)” |
|
<term > |
::= |
<term >“.”<component > | <term >“/”<component > | <component > |
|
<main-term > |
::= |
|
|
<annotation > |
::= |
“{”<ANNOTATION-STRING >“}” |
The following tables define prefixes and unit symbols. The columns define:
- The UCUM representation (Symbol (c/s))
- The full name (Display Name)
- The Print Symbol – recommended for display and printing
- Value (for prefixes) is the scalar value by which the unit atom is multiplied if combined with the prefix.
- Kind of Quantity (for units) is the quantity name.
Full name and print symbol are defined by other bodies and are out of scope of The Unified Code for Units of Measure.
|
The prefix symbols |
|||
|
Symbol (c/s) |
Display Name |
Print Symbol |
value |
|
Y |
yotta |
Y |
1 × 1024 |
|
Z |
zetta |
Z |
1 × 1021 |
|
E |
exa |
E |
1 × 1018 |
|
P |
peta |
P |
1 × 1015 |
|
T |
tera |
T |
1 × 1012 |
|
G |
giga |
G |
1 × 109 |
|
M |
mega |
M |
1 × 106 |
|
k |
kilo |
k |
1 × 103 |
|
h |
hecto |
h |
1 × 102 |
|
da |
deka |
da |
1 × 101 |
|
d |
deci |
d |
1 × 10-1 |
|
c |
centi |
c |
1 × 10-2 |
|
m |
milli |
m |
1 × 10-3 |
|
u |
micro |
μ |
1 × 10-6 |
|
n |
nano |
n |
1 × 10-9 |
|
p |
pico |
p |
1 × 10-12 |
|
f |
femto |
f |
1 × 10-15 |
|
a |
atto |
a |
1 × 10-18 |
|
z |
zepto |
z |
1 × 10-21 |
|
y |
yocto |
y |
1 × 10-24 |
|
The special prefix symbols for powers of 2 NOTE These symbols are for use in information technology as proposed by the IEEE. |
|||
|
Symbol (c/s) |
Display Name |
Print Symbol |
value |
|
Ki |
kibi |
Ki |
1 × 10241 |
|
Mi |
mebi |
Mi |
1 × 10242 |
|
Gi |
gibi |
Gi |
1 × 10243 |
|
Ti |
tebi |
Ti |
1 × 10244 |
|
Pi |
pebi |
Pi |
1 × 10245 |
|
Ei |
exbi |
Ei |
1 × 10246 |
|
Zi |
zebi |
Zi |
1 × 10247 |
|
Yi |
yobi |
Yi |
1 × 10248 |
The base units are used to define all the unit atoms of The Unified Code for Units of Measure according to its grammar and semantics.
The selection of the base and the order of the units in the base are not normative. Any other base is acceptable as long as there is an isomorphism between the group of units generated by the other base system and this one. All base units are metric.
|
Symbol (c/s) |
Display Name |
Print Symbol |
Kind of Quantity |
Metric |
|
m |
meter |
m |
length |
yes |
|
s |
second |
s |
time |
yes |
|
g |
gram |
g |
mass |
yes |
|
rad |
radian |
rad |
plane angle |
yes |
|
K |
kelvin |
K |
temperature |
yes |
|
C |
coulomb |
C |
electric charge |
yes |
|
cd |
candela |
cd |
luminous intensity |
yes |
|
NOTE 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 NOTE 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 |
|
CGS units NOTE 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 |
.
|
International customary units NOTE The unified U.S. and British Imperial customary units, so called "international" customary units |
||||
|
Symbol (c/s) |
Display Name |
Print Symbol |
Kind of Quantity |
Metric |
|
[in_i] |
inch |
in |
length |
no |
|
[ft_i] |
foot |
ft |
length |
no |
|
[yd_i] |
yard |
yd |
length |
no |
|
[mi_i] |
mile |
mile |
length |
no |
|
[fth_i] |
fathom |
fth |
depth of water |
no |
|
[nmi_i] |
nautical mile |
n mile |
length |
no |
|
[kn_i] |
knot |
kn |
velocity |
no |
|
[sin_i] |
square inch |
In2 |
area |
no |
|
[sft_i] |
square foot |
ft2 |
area |
no |
|
[syd_i] |
square yard |
yd2 |
area |
no |
|
[cin_i] |
cubic inch |
In3 |
volume |
no |
|
[cft_i] |
cubic foot |
ft3 |
volume |
no |
|
[cyd_i] |
cubic yard |
yd3 |
volume |
no |
|
[bf_i] |
board foot |
fbm |
volume |
no |
|
[cr_i] |
cord |
cord |
volume |
no |
|
[mil_i] |
mil |
mil |
length |
no |
|
[cml_i] |
circular mil |
cmil |
area |
no |
|
[hd_i] |
hand |
|
height of horses |
no |
|
Older U.S. "survey" lengths NOTE also called “statute” lengths |
||||
|
Symbol (c/s) |
Display Name |
Print Symbol |
Kind of Quantity |
Metric |
|
[ft_us] |
foot |
ft (US survey) |
length |
no |
|
[yd_us] |
yard |
|
length |
no |
|
[in_us] |
inch |
|
length |
no |
|
[rd_us] |
rod |
|
length |
no |
|
[ch_us] |
Gunter's chain, Surveyor's chain |
|
length |
no |
|
[lk_us] |
link for Gunter's chain |
|
length |
no |
|
[rch_us] |
Ramden's chain, Engineer's chain |
|
length |
no |
|
[rlk_us] |
link for Ramden's chain |
|
length |
no |
|
[fth_us] |
fathom |
|
length |
no |
|
[fur_us] |
furlong |
|
length |
no |
|
[mi_us] |
mile |
mi (US survey) |
length |
no |
|
[acr_us] |
acre |
|
area |
no |
|
[srd_us] |
square rod |
|
area |
no |
|
[smi_us] |
square mile |
Mi2 (US survey) |
area |
no |
|
[sct] |
section |
|
area |
no |
|
[twp] |
township |
|
area |
no |
|
[mil_us] |
mil |
|
length |
no |
|
British Imperial lengths |
||||
|
Symbol (c/s) |
Display Name |
Print Symbol |
Kind of Quantity |
Metric |
|
[in_br] |
inch |
|
length |
no |
|
[ft_br] |
foot |
|
length |
no |
|
[rd_br] |
rod |
|
length |
no |
|
[ch_br] |
Gunter's chain |
|
length |
no |
|
[lk_br] |
link for Gunter's chain |
|
length |
no |
|
[fth_br] |
fathom |
|
length |
no |
|
[pc_br] |
pace |
|
length |
no |
|
[yd_br] |
yard |
|
length |
no |
|
[mi_br] |
mile |
|
length |
no |
|
[nmi_br] |
nautical mile |
|
length |
no |
|
[kn_br] |
knot |
|
velocity |
no |
|
[acr_br] |
acre |
|
area |
no |
|
U.S. volumes NOTE Including so-called “dry measures” |
||||
|
Symbol (c/s) |
Display Name |
Print Symbol |
Kind of Quantity |
Metric |
|
[gal_us] |
Queen Anne's wine gallon |
|
fluid volume |
no |
|
[bbl_us] |
barrel |
barrel (US) |
fluid volume |
no |
|
[qt_us] |
quart |
liq qt (US) |
fluid volume |
no |
|
[pt_us] |
pint |
liq pt (US) |
fluid volume |
no |
|
[gil_us] |
gill |
gi (US) |
fluid volume |
no |
|
[foz_us] |
fluid ounce |
fl oz (US) |
fluid volume |
no |
|
[fdr_us] |
fluid dram |
|
fluid volume |
no |
|
[min_us] |
minim |
|
fluid volume |
no |
|
[crd_us] |
cord |
|
fluid volume |
no |
|
[bu_us] |
bushel |
|
dry volume |
no |
|
[gal_wi] |
historical winchester gallon |
|
dry volume |
no |
|
[pk_us] |
peck |
|
dry volume |
no |
|
[dqt_us] |
dry quart |
|
dry volume |
no |
|
[dpt_us] |
dry pint |
|
dry volume |
no |
|
[tbs_us] |
tablespoon |
|
volume |
no |
|
[tsp_us] |
teaspoon |
|
volume |
no |
|
[cup_us] |
cup |
|
volume |
no |
|
[foz_m] |
metric fluid ounce |
|
fluid volume |
no |
|
[cup_m] |
metric cup |
|
volume |
no |
|
[tsp_m] |
metric teaspoon |
|
volume |
no |
|
[tbs_m] |
metric tablespoon |
|
volume |
no |
|
British Imperial volumes |
||||
|
Symbol (c/s) |
Display Name |
Print Symbol |
Kind of Quantity |
Metric |
|
[gal_br] |
gallon |
gal (UK) |
volume |
no |
|
[pk_br] |
peck |
pk (UK) |
volume |
no |
|
[bu_br] |
bushel |
bushel (UK) |
volume |
no |
|
[qt_br] |
quart |
qt (UK) |
volume |
no |
|
[pt_br] |
pint |
pt (UK) |
volume |
no |
|
[gil_br] |
gill |
gi (UK) |
volume |
no |
|
[foz_br] |
fluid ounce |
fl oz (UK) |
volume |
no |
|
[fdr_br] |
fluid dram |
|
volume |
no |
|
[min_br] |
minim |
|
volume |
no |
|
Avoirdupois weights |
||||
|
Symbol (c/s) |
Display Name |
Print Symbol |
Kind of Quantity |
Metric |
|
[gr] |
grain |
|
mass |
no |
|
[lb_av] |
pound |
|
mass |
no |
|
[oz_av] |
ounce |
|
mass |
no |
|
[dr_av] |
dram |
|
mass |
no |
|
[scwt_av] |
short hundredweight, U.S. hundredweight |
|
mass |
no |
|
[lcwt_av] |
long hunderdweight, British hundredweight |
|
mass |
no |
|
[ston_av] |
short ton, U.S. ton |
|
mass |
no |
|
[lton_av] |
long ton, British ton |
|
mass |
no |
|
[stone_av] |
stone, British stone |
|
mass |
no |
|
Troy weights |
||||
|
Symbol (c/s) |
Display Name |
Print Symbol |
Kind of Quantity |
Metric |
|
[pwt_tr] |
pennyweight |
|
mass |
no |
|
[oz_tr] |
ounce |
|
mass |
no |
|
[lb_tr] |
pound |
|
mass |
no |
|
Units used in typesetting |
||||
|
Symbol (c/s) |
Display Name |
Print Symbol |
Kind of Quantity |
Metric |
|
[lne] |
line |
|
length |
no |
|
[pnt] |
point |
|
length |
no |
|
[pca] |
pica |
|
length |
no |
|
[pnt_pr] |
Printer's point |
|
length |
no |
|
[pca_pr] |
Printer's pica |
|
length |
no |
|
[pied] |
pied, French foot |
|
length |
no |
|
[pouce] |
pouce, French inch |
|
length |
no |
|
[ligne] |
ligne, French line |
|
length |
no |
|
[didot] |
didot, Didot's point |
|
length |
no |
|
[cicero] |
cicero, Didot's pica |
|
length |
no |
|
Legacy Units for Heat and Temperature |
||||
|
Symbol (c/s) |
Display Name |
Print Symbol |
Kind of Quantity |
Metric |
|
[degF] |
degree Fahrenheit |
°F |
temperature |
no |
|
[degR] |
degree Rankine |
°R |
temperature |
no |
|
[degRe] |
degree Réaumur |
°Ré |
temperature |
no |
|
cal_[15] |
calorie at 15 °C |
cal15°C |
energy |
yes |
|
cal_[20] |
calorie at 20 °C |
cal20°C |
energy |
yes |
|
cal_m |
mean calorie |
calm |
energy |
yes |
|
cal_IT |
international table calorie |
calIT |
energy |
yes |
|
cal_th |
thermochemical calorie |
calth |
energy |
yes |
|
cal |
calorie |
cal |
energy |
yes |
|
[Cal] |
nutrition label Calories |
Cal |
energy |
no |
|
[Btu_39] |
British thermal unit at 39 °F |
Btu39°F |
energy |
no |
|
[Btu_59] |
British thermal unit at 59 °F |
Btu59°F |
energy |
no |
|
[Btu_60] |
British thermal unit at 60 °F |
Btu60°F |
energy |
no |
|
[Btu_m] |
mean British thermal unit |
Btum |
energy |
no |
|
[Btu_IT] |
international table British thermal unit |
BtuIT |
energy |
no |
|
[Btu_th] |
thermochemical British thermal unit |
Btuth |
energy |
no |
|
[BTU] |
British thermal unit |
btu |
energy |
no |
|
[HP] |
horsepower |
|
power |
no |
|
TEX |
tex |
tex |
linear mass density (of textile thread) |
yes |
|
[DEN] |
Denier |
den |
linear mass density (of textile thread) |
no |
|
Units Used Predominantly in Clinical Medicine |
||||
|
Symbol (c/s) |
Display Name |
Print Symbol |
Kind of Quantity |
Metric |
|
m[H2O] |
meter of water column |
m H2O |
pressure |
yes |
|
m[Hg] |
meter of mercury column |
m Hg |
pressure |
yes |
|
[in_i'H2O] |
inch of water column |
in H2O |
pressure |
no |
|
[in_i'Hg] |
inch of mercury column |
in Hg |
pressure |
no |
|
[PRU] |
peripheral vascular resistance unit |
P.R.U. |
fluid resistance |
no |
|
[wood'U] |
Wood unit |
Wood U. |
fluid resistance |
no |
|
[diop] |
diopter |
dpt |
refraction of a lens |
no |
|
[p'diop] |
prism diopter |
PD |
refraction of a prism |
no |
|
%[slope] |
percent of slope |
% |
slope |
no |
|
[mesh_i] |
mesh |
|
lineic number |
no |
|
[Ch] |
Charrière, french |
Ch |
gauge of catheters |
no |
|
[drp] |
drop |
drp |
volume |
no |
|
[hnsf'U] |
Hounsfield unit |
HF |
x-ray attenuation |
no |
|
[MET] |
metabolic equivalent |
MET |
metabolic cost of physical activity |
no |
|
[hp'_X] |
homeopathic potency of decimal series (retired) |
X |
homeopathic potency (retired) |
no |
|
[hp'_C] |
homeopathic potency of centesimal series (retired) |
C |
homeopathic potency (retired) |
no |
|
[hp'_M] |
homeopathic potency of millesimal series (retired) |
M |
homeopathic potency (retired) |
no |
|
[hp'_Q] |
homeopathic potency of quintamillesimal series (retired) |
Q |
homeopathic potency (retired) |
no |
|
[hp_X] |
homeopathic potency of decimal hahnemannian series |
X |
homeopathic potency (Hahnemann) |
no |
|
[hp_C] |
homeopathic potency of centesimal hahnemannian series |
C |
homeopathic potency (Hahnemann) |
no |
|
[hp_M] |
homeopathic potency of millesimal hahnemannian series |
M |
homeopathic potency (Hahnemann) |
no |
|
[hp_Q] |
homeopathic potency of quintamillesimal hahnemannian series |
Q |
homeopathic potency (Hahnemann) |
no |
|
[kp_X] |
homeopathic potency of decimal korsakovian series |
X |
homeopathic potency (Korsakov) |
no |
|
[kp_C] |
homeopathic potency of centesimal korsakovian series |
C |
homeopathic potency (Korsakov) |
no |
|
[kp_M] |
homeopathic potency of millesimal korsakovian series |
M |
homeopathic potency (Korsakov) |
no |
|
[kp_Q] |
homeopathic potency of quintamillesimal korsakovian series |
Q |
homeopathic potency (Korsakov) |
no |
|
Units used in Chemical and Biomedical Laboratories |
||||
|
Symbol (c/s) |
Display Name |
Print Symbol |
Kind of Quantity |
Metric |
|
eq |
equivalents |
eq |
amount of substance |
yes |
|
osm |
osmole |
osm |
amount of substance (dissolved particles) |
yes |
|
[pH] |
pH |
pH |
acidity |
no |
|
g% |
gram percent |
g% |
mass concentration |
yes |
|
[S] |
Svedberg unit |
S |
sedimentation coefficient |
no |
|
[HPF] |
high power field |
HPF |
view area in microscope |
no |
|
[LPF] |
low power field |
LPF |
view area in microscope |
no |
|
kat |
katal |
kat |
catalytic activity |
yes |
|
U |
Unit |
U |
catalytic activity |
yes |
|
[iU] |
international unit |
IU |
arbitrary |
yes |
|
[IU] |
international unit |
i.U. |
arbitrary |
yes |
|
[arb'U] |
arbitary unit |
arb. U |
arbitrary |
no |
|
[USP'U] |
United States Pharmacopeia unit |
U.S.P. |
arbitrary |
no |
|
[GPL'U] |
GPL unit |
|
biologic activity of anticardiolipin IgG |
no |
|
[MPL'U] |
MPL unit |
|
biologic activity of anticardiolipin IgM |
no |
|
[APL'U] |
APL unit |
|
biologic activity of anticardiolipin IgA |
no |
|
[beth'U] |
Bethesda unit |
|
biologic activity of factor VIII inhibitor |
no |
|
[anti'Xa'U] |
anti factor Xa unit |
|
biologic activity of factor Xa inhibitor (heparin) |
no |
|
[todd'U] |
Todd unit |
|
biologic activity antistreptolysin O |
no |
|
[dye'U] |
Dye unit |
|
biologic activity of amylase |
no |
|
[smgy'U] |
Somogyi unit |
|
biologic activity of amylase |
no |
|
[bdsk'U] |
Bodansky unit |
|
biologic activity of phosphatase |
no |
|
[ka'U] |
King-Armstrong unit |
|
biologic activity of phosphatase |
no |
|
[knk'U] |
Kunkel unit |
|
arbitrary biologic activity |
no |
|
[mclg'U] |
Mac Lagan unit |
|
arbitrary biologic activity |
no |
|
[tb'U] |
tuberculin unit |
|
biologic activity of tuberculin |
no |
|
[CCID_50] |
50% cell culture infectious dose |
CCID50 |
biologic activity (infectivity) of an infectious agent preparation |
no |
|
[TCID_50] |
50% tissue culture infectious dose |
TCID50 |
biologic activity (infectivity) of an infectious agent preparation |
no |
|
[EID_50] |
50% embryo infectious dose |
EID50 |
biologic activity (infectivity) of an infectious agent preparation |
no |
|
[PFU] |
plaque forming units |
PFU |
amount of an infectious agent |
no |
|
[FFU] |
focus forming units |
FFU |
amount of an infectious agent |
no |
|
[CFU] |
colony forming units |
CFU |
amount of a proliferating organism |
no |
|
[IR] |
index of reactivity |
IR |
amount of an allergen calibrated through in-vivo testing using the Stallergenes® method. |
no |
|
[BAU] |
bioequivalent allergen unit |
BAU |
amount of an allergen calibrated through in-vivo testing based on the ID50EAL method of (intradermal dilution for 50mm sum of erythema diameters |
no |
|
[AU] |
allergen unit |
AU |
procedure defined amount of an allergen using some reference standard |
no |
|
[Amb'a'1'U] |
allergen unit for Ambrosia artemisiifolia |
Amb a 1 U |
procedure defined amount of the major allergen of ragweed. |
no |
|
[PNU] |
protein nitrogen unit |
PNU |
procedure defined amount of a protein substance |
no |
|
[Lf] |
Limit of flocculation |
Lf |
procedure defined amount of an antigen substance |
no |
|
[D'ag'U] |
D-antigen unit |
|
procedure defined amount of a poliomyelitis d-antigen substance |
no |
|
[FEU] |
fibrinogen equivalent unit |
|
amount of fibrinogen broken down into the measured d-dimers |
no |
|
[ELU] |
ELISA unit |
|
arbitrary ELISA unit |
no |
|
[EU] |
Ehrlich unit |
|
Ehrlich unit |
no |
.
|
Levels NOTE Pseudo-units defined to express logarithms of ratios between two quantities of the same kind |
||||
|
Symbol (c/s) |
Display Name |
Print Symbol |
Kind of Quantity |
Metric |
|
Np |
neper |
Np |
level |
yes |
|
B |
bel |
B |
level |
yes |
|
B[SPL] |
bel sound pressure |
B(SPL) |
pressure level |
yes |
|
B[V] |
bel volt |
B(V) |
electric potential level |
yes |
|
B[mV] |
bel millivolt |
B(mV) |
electric potential level |
yes |
|
B[uV] |
bel microvolt |
B(μV) |
electric potential level |
yes |
|
B[10.nV] |
bel 10 nanovolt |
B(10 nV) |
electric potential level |
yes |
|
B[W] |
bel watt |
B(W) |
power level |
yes |
|
B[kW] |
bel kilowatt |
B(kW) |
power level |
yes |
|
Miscellaneous Units |
||||
|
Symbol (c/s) |
Display Name |
Print Symbol |
Kind of Quantity |
Metric |
|
st |
stere |
st |
volume |
yes |
|
Ao |
Ångström |
Å |
length |
no |
|
b |
barn |
b |
action area |
no |
|
att |
technical atmosphere |
at |
pressure |
no |
|
mho |
mho |
mho |
electric conductance |
yes |
|
[psi] |
pound per sqare inch |
psi |
pressure |
no |
|
circ |
circle |
circ |
plane angle |
no |
|
sph |
spere |
sph |
solid angle |
no |
|
[car_m] |
metric carat |
ctm |
mass |
no |
|
[car_Au] |
carat of gold alloys |
ctAu |
mass fraction |
no |
|
[smoot] |
Smoot |
|
length |
no |
|
[m/s2/Hz^(1/2)] |
meter per square seconds per square root of hertz |
|
amplitude spectral density |
no |
|
Units used in Information Science and Technology |
||||
|
Symbol (c/s) |
Display Name |
Print Symbol |
Kind of Quantity |
Metric |
|
bit_s |
bit |
bits |
amount of information |
no |
|
bit |
bit |
bit |
amount of information |
yes |
|
By |
byte |
B |
amount of information |
yes |
|
Bd |
baud |
Bd |
signal transmission rate |
yes |
|
Examples for Non-Units |
||||
|
Symbol (c/s) |
Display Name |
Print Symbol |
Kind of Quantity |
Metric |
|
{tot} |
particles total count |
tot. |
number |
no |
|
{tbl} |
tablets |
tbl. |
number |
no |
|
{rbc} |
red blood cell count |
R.B.C. |
number |
no |
|
g.m/{H.B.} |
gram meter per heartbeat |
g·m/H.B. |
proportional to ventricular stroke work |
no |
|
gf.m/{H.B.} |
gram-force meter per heartbeat |
gf·m/H.B. |
ventricular stroke work |
no |
|
kg{wet'tis} |
kilogram of wet tissue |
kg(wet tissue) |
mass |
no |
|
mg{creat} |
milligram of creatinine |
mg(creat.) |
mass |
no |