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Highway Addresable Remote Transducer
Open protocol that supports two way digital communications for process measurement and control devices.
Further Reading



A widely used nickel-molybdenum-chromium alloy.
Offers excellent resistance to wet chlorine, hypochlorite bleach, ferric chloride and nitric acid.
Further Reading



Hand Arm Vibration Syndrome
A potentially debilitating disorder resulting from prolonged exposure to vibration - specifically to the hands and forearms while using vibrating tools.
Further Reading


Hazid - Hazard Identification

The process of identifying credible hazards for a Quantified Risk Assessment (QRA)

Further Reading



Hazard and Operability Review

Further Reading
HAZOP Toolbox Page


A chemical compound that consists only of hydrogen (H) and carbon (C).
Further Reading



Heating Value is defined as the amount of energy released when a fuel is burned completely in a steady-flow process and the products are returned to the state of the reactants.
The heating value is dependent on the phase of water/steam in the combustion products. If H2O is in liquid form the heating value is called HHV (Higher Heating Value).
Further Reading



High Integrity Protective System - or sometimes High Integrity Protection System
An automatic safety system with a SIL level of 3 or more
Further Reading
SIL Ratings Toolbox Page


Helicopter Landing Officer

Further Reading



Heavy Lift Vessel

Further Reading


HMI - Human Machine Interface

A dated term superseded by SCADA

Further Reading


Hot Work

This includes welding or the use of any flame or electric arc or the use of any equipment likely to cause heat or flame or spark.

Further Reading


HP - High Pressure

Often used with reference to a utility or vent line e.g. HP air supply

Further Reading



Hydraulic Power Unit

Further Reading
Hydraulic Cleanliness Toolbox Page


Health Safety and Environment

Further Reading


HSE - Health and Safety Executive

Authority responsible for the regulation of almost all the risks to health and safety arising from work activity in Britain.

Further Reading



Helicopter Underwater Escape Training
Part of the Basic Offshore Induction and Emergency Training course where participants swim from an inverted helicopter submerged in a swimming pool.
Further Reading
Guide to Offshore Survival Course


Heating Ventilating and Air Conditioning

Further Reading



A pressure test of piping; pressure vessels or pressure-containing parts; usually performed by pressurising the internal volume with water.

Further Reading



HYprotech SYStems process modeling software by AspenTech
Used for steady state simulation; design; performance monitoring; optimization and business planning for oil & gas production; gas processing and petroleum refining industries.
Further Reading


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