Reference
Plumbing & Fire Protection Abbreviations
Common abbreviations found on plumbing and fire protection drawings. Quick reference for interpreting mechanical plans and specifications.
Categories
Access & Inspection
AP
Access Panel
CO
Cleanout
FCO
Floor Cleanout
GCO
Ground Clean Out
Fixtures & Appliances
BT
Bath Tub
DF
Drinking Fountain
EWC
Electrical Water Cooler
Alternative term for drinking fountain
MSB
Mop Service Basin
SH / SHWR
Shower
SK
Sink
TLT
Toilet
U
Urinal
WC
Water Closet
Toilet
Piping & Materials
CI
Cast Iron
CLDI
Cement Lined Ductile Iron
CONC
Concrete
CP
Chrome Plated
GALV
Galvanized
GI
Grease Interceptor
ID
Inside Diameter
OD
Outside Diameter
SS
Soil Stack or Stainless Steel
Water Systems
CW
Cold Water
CWR
Cold Water Return
CWS
Cold Water Supply
HW
Hot Water
HWR
Hot Water Return
HWS
Hot Water Supply
TW
Tempered Water
Valves & Flow Control
BWV
Back Water Valve
DCVA
Double Check Valve Assembly
FHV
Fire Hose Valve
FV
Flush Valve
NC
Normally Closed
NO
Normally Open
PIV
Post Indicator Valve
RPBP
Reduced Pressure Backflow Preventer
VB
Vacuum Breaker
Drainage
IW
Indirect Waste
OED
Open End Drain
SD
Sanitary Drain
W
Waste
WS
Waste Stack
Venting
V
Vent
VS
Vent Stack
VTR
Vent Through Roof
Fire Protection
FEC
Fire Extinguisher Cabinet
FP
Fire Protection
FPWH
Freeze Proof Wall Hydrant
FS
Flow Switch
TS
Tamper Switch
WH
Wall Hydrant
Measurements & General
CFH
Cubic Feet per Hour
CFM
Cubic Feet per Minute
DIA
Diameter
EL / ELEV
Elevation
FLR
Floor
FT
Foot or Feet
GPF
Gallons per Flush
GPM
Gallons per Minute
INV
Invert
MECH
Mechanical
PLBG
Plumbing
PSI
Pounds per Square Inch
SA
Shock Absorber
TYP
Typical
VFD
Variable Frequency Drive
Related Resources
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Helonic's AI understands plumbing abbreviations and can identify coordination issues, verify fixture counts, and flag discrepancies across your MEP drawing set.
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