Name Acronym Description
Health Protection Agency Centre for Radiation, Chemical and Environmental Hazards HPA CRCE

A specialist centre of HPA which deals with radiation and chemical hazards and threats.

Health Protection Scotland HPS

Established by the Scottish Government to strengthen and co-ordinate health protection in Scotland.

Heat flux

Heat flux or thermal flux is the rate of heat energy transfer through a given surface per unit time. The SI derived unit of heat rate is joule per second, or watt. Heat flux density is the heat rate per unit area.

Helical flow

Found along a shoreline and is a corkscrew or spring-like current that is constantly rolling and pushing out into the laminar flow. This spiral water flow can sweep a person off their feet and push them into the main current or make swimming back to shore a challenge

High Rise Building

For Fire Service purposes a high rise building may be considered as a building that contains 5 floors above fire service access level or the height of the highest floor is more than 18m above that level.

High-expansion foam HX

High-expansion foams have an expansion ratio over 200 - 1000. They are suitable for enclosed spaces such as hangars, where quick filling is needed.

Highways Agency Managed Motorways

A managed motorway entails the permanent conversion of the hard shoulder to a running lane, whilst retaining the ability to dynamically control traffic

Horizontal fuel arrangement

A description of the distribution of fuels on the horizontal plane. The horizontal arrangement of fuels will influence the relative ease with which fire can spread horizontally across an area of land

Hydraulic injection

Hydraulic injection can be defined as the puncturing of the epidermis by a jet of a fluid under pressure

Immediate care practitioners

Highly trained doctors who provide their services in support of the ambulance service

Improvised decontamination

Public decontamination using an immediately available method (wet or dry) before the use of specialist resources, such as blotting with paper tissues, washing in on-site facilities etc.

Incident log

A timeline record of all significant decisions, actions and information received that is used to develop the incident operational plan and inform the de-briefing process.

Inflatable tubular system

A type of airbag system.

Inland water categories

Inland waters are classified as one of four categories:
Category A - narrow rivers and canals where the depth of water is generally less than 1.5 metres
Category B - wider rivers and canals where the depth of water is generally 1.5 metres or more and where the significant wave height could not be expected to exceed 0.6 metres at any time
Category C - tidal rivers, estuaries and large, deep lakes and lochs where the significant wave height could not be expected to exceed 1.2 metres at any time
Category D - tidal rivers and estuaries where the significant wave height could not be expected to exceed 2 metres at any time

Instrument landing system ILS

Electronic navigation system that provides guidance information to allow aircraft to approach and land, including during inclement weather conditions.

Integrated Risk Management Plan IRMP

The planning process and subsequent plan for a fire and rescue authority to demonstrate how its strategic direction meets the needs of the community

Inter-Agency Liaison Officer IALO or ILO

A Fire and Rescue Service officer who can advise and support Incident Commanders, Police, Medical, Military and other Government Agencies on the organisation’s operational capacity and capability to reduce risk and safely resolve incidents at where an attendance may be required. This will include major incidents, public order, domestic or any other situation that would benefit from the attendance of the ILO.

Interim decontamination

The use of standard fire and rescue service equipment to provide a planned and structured 'wet' decontamination process for members of the public.

International Atomic Energy Agency IAEA

The IAEA is the world´s centre of cooperation in the nuclear field. It was set up as the world´s "Atoms for Peace" organization in 1957 within the United Nations family. The Agency works with its Member States and multiple partners worldwide to promote safe, secure and peaceful nuclear technologies.

International Commission on Radiological Protection ICRP

An advisory body providing recommendations and guidance on radiation protection

International Maritime Dangerous Goods code IMDG

IMDG code is accepted as an international guideline to the safe transport or shipment of dangerous goods or hazardous materials by vessel on water.

International Maritime Organisation IMO

United Nations specialised agency that has developed international legislation dealing with the safety of life at sea and the prevention of pollution from ships.

International Nuclear & Radiological Event Scale INES

A tool for promptly communicating to the public in consistent terms the safety significance of reported nuclear and radiological incidents and accidents.

International ship-to-shore firefighting connection

An international shore connection to be used with marine firefighting systems during an emergency when a stricken ship has a system failure. International shore connections are portable universal couplings that permit connection of shipboard fire main systems between one ship and another or between a shore facility and a ship when their respective system threading is mismatched. Both the ship and the facility are expected to have a fitting such that in an
emergency can be attached to their respective fire hose and bolted together to permit charging
the ship's system.

Intrinsically safe

Intrinsically safe equipment has been designed and tested to not become an ignition source in a flammable atmosphere