H
- H
- Hackers
- Hanger Accessories – Examples: Pipe Clamp, Hanger Rod, Turnbuckle, Beam Clamp
- Hanger Arm
- Hard Seated Valve
- Hard-Desk
- Hardening
- Harmonised Standard
- Hazard
- Hazard and Operability Study
- Hazardous Area
- Hazardous Area Classification
- Hazardous Atmosphere
- HAZID
- Health and Safety Executive
- Heat Distortion Temperature
- HFT
- High Frequency Welded Pipe
- High Level Alarm
- Hose Drain
- Hot (System) – Equivalent: On-Line, Operating, On-Stream, Live
- Hot Tap
- Human-Computer Interface
- Hybrid Mixture
- Hydrogen Embrittlement