At, we do our best to use standardized nomenclature to describe our products. Frequently we also use abbreviations to describe product details. If the terminologies and/or abbreviations used on this site are confusing or unclear, we hope this glossary of abbreviations and terms will help. Glossary of Abbreviations and Terms

~ Tilde Sign: Used to indicate an estimate, i.e. ~7 min =  approximately 7 minutes
± Plus-Minus Sign: Indicates the precision of an approximation, i.e. ±5°F = plus or minus 5 degrees Fahrenheit
' Apostrophe: Foot/Feet, i.e. 5'
" Quotation Mark: Inch/Inches, i.e. 11"
° Degree Sign
A or amp Amperage
Ar Argon
bar Metric Unit of Pressure (1 bar = 14.5 psi)
C Centigrade (Metric)
cc/min Cubic Centimeters per Minute
CFM Cubic Feet per Minute
cm Centimeter/Centimeters
CO Carbon Monoxide
CO2 or CO2 Carbon Dioxide
cSt Centistrokes
cu ft Cubic Feet
dB Decibels
E1 Single Phase
E3 Three Phase
EAN or EANx Enriched Air Nitrox
EANx32, EANx36, etc. Enriched Air Nitrox, i.e. EANx40 = 40% oxygen
F Fahrenheit (Imperial)
FAD Free Air Delivery
Fill Time (CFM/ACFM) Fill time based on filling an 80 cu ft tank from 0 to 3000 psi. (Calculation: 80 ÷ CFM/ACFM Rate = CFM/ACFM Fill Time)
Sometimes referred to as "Charging Rate"
Fill Time (SCFM) Fill time based on filling an 80 cu ft cylinder from 500 to 3000 psi. (Calculation: 80 ÷ SCFM Rate x 0.8333 = SCFM Fill Time)
Sometimes referred to as "Charging Rate"
ft Foot/Feet
g Gram/Grams
g/L Grams per Liter
gal Gallon/Gallons
hp Horsepower
He Helium
Hz Hertz
I.D. or ID Inner (interior) diameter of a tube, pipe, or hose
in Inch/Inches
inHg Inches of Mercury (vacuum)
kg Kilograms
kW Kilowatt
L Liter 
L x W x H Dimensions of a Product: Length x Width x Height
L/min Liters per Minute
lb Pound/Pounds [Weight]
m Meter/Meters
m3/h Cubic Meters per Hour 
mA Milliamp
min Minute/Minutes
mL Milliliter/Milliliters
mm Millimeter/Millimeters
mV Millivolt/Millivolts
N2 or N2 Nitrogen
Nitrox Enriched air oxygen, oxygen enriched air, EAN, EANx
O2 or O2 Oxygen
OCA Oxygen Compatible Air
O.D. or OD Outer diameter of a tube, pipe, or hose
oz Ounce/Ounces in Volume or Weight
ppm Parts per Million
psi Pounds per Square Inch: Imperial Unit of Pressure (100 psi = 6.89 bar)
qt Quart/Quarts
rh Relative Humidity
RPM Revolutions per Minute
SCBA Self-Contained Breathing Apparatus
SCFM Standard Cubic Feet per Minute
SCUBA or scuba Self-Contained Underwater Breathing Apparatus
SKU Stock Keeping Unit: Used as Nuvair's product identification number
V Volt