Guidance

Management of health and safety in defence: master glossary

Updated 19 January 2026

Numbers

Term	Abbreviation	Definition
4Cs		Co-ordination, co-operation, communication, and control.
4Cs Appointed Person	4CsAP	A person with the appropriate management attributes, competence and authority, who has been formally appointed by the accountable person for their unit, to oversee the process for the management of visiting workers and contractors.

A

Term	Abbreviation	Definition
Absorption		Uptake of material into the body, for example, the blood, cells, organs and so on. Skin along with inhalation, ingestion and injection are routes by which substances can enter the body. (see also inhalation and ingestion).
Accident		An unintended event that results in injury, ill health or death to a person(s).
Acclimatised		When personnel in hot environments have undergone a graded supervised programme of increasing exercise to adapt to the conditions. All personnel in the UK and Northern Europe, and those in hot environments who have not undergone a graded supervised programme of increasing exercise to adapt to the environment, are to be considered to be not acclimatised.
Accountability / accountable		A person who is liable and holds responsibility for risk management and the effectiveness of a single, or many activities to agreed standards or criteria.
Accountable Person	AP	The person whose terms of reference state that they are responsible for making sure there are suitable and sufficient systems in place to control health and safety risks in their unit, establishment, site or platform. This term is used in place of CO, HoE, OC, Station Commander and so on, or as decreed by the Defence organisations.
Acute effects		Health effect which appears within a short period of exposure to the causative agent.  Usually associated with short-term, high-level exposure.
Additive / synergistic		Substances said to be additive are those having or relating to an effect that is the sum of individual effects. Those said to be synergistic in their effects when they act either on the same organs or by the same mechanisms so that the overall effect is considerably greater than the sum of the individual effects. This may arise from mutual enhancement of the effects of the constituents or because one substance ‘potentiates’ another causing it to act in a way it would not if used on its own.
Advice		Providing specific and practical direction on the action(s) to be taken to ensure compliance. Advice stops short of telling a participant exactly what to do, but if followed, should contribute to enabling a compliant solution.
Alternative acceptable means of compliance	AAMC	An alternative way of meeting a requirement of JSP 375 policy, as approved by the Director of Defence Safety (Director DS).
Appointed doctor		An appointed doctor is a registered medical practitioner appointed by the Health and Safety Executive (HSE) to undertake statutory Medical Surveillance.
Appointed Person (First Aid)		A person appointed to take charge of specific arrangements (for example, first aid or 4Cs) on behalf of the accountable person, commander or manager, including checking First Aid equipment and calling emergency services when required but not conducting first-aid. This person is appointed in lieu of a formal First Aider being available.
Arduous		A physical activity demanding great exertion or effort.
Area Custodian		A person of suitable rank or grade, with appropriate knowledge and experience, appointed by their line manager (in consultation with the 4Cs Appointed Person) to compile a hazard register(s) for their 4Cs Area(s) of responsibility and to communicate and co-ordinate on health and safety matters with any visiting workers / contractors, prior to work commencing. On some sites, this could be subsumed as part of another role.
Area of responsibility	AoR	The physical area, activities, or operational parameters for which an individual or organisation has direct control over or delegated authority for financial matters.
As low as reasonably practicable	ALARP	When risk has been reduced to a level where applying further control measures would be grossly disproportionate to the benefit that would be gained.
Asbestos containing materials	ACM	Any material or article that, as part of its design, contains asbestos (such as insulating boards, lagging, gaskets, and so on).
Asbestos survey		A formal assessment to determine/confirm and record the location, quantity, type, and condition of Asbestos Containing Material (ACM).
Assessment		The formal review of a safety document or other written product.
ASIMS	ASIMS	Air Safety Information Management System.
Assurance		A general term for the confidence that can be derived from objective examination of information over the successful conduct of activities, the efficient and effective design and operation of internal control, compliance with internal and external requirements, and the production of insightful and credible information to support decision-making. Confidence diminishes when there are uncertainties around the integrity of information or of underlying processes.
Audiometric health surveillance		Regular hearing checks in controlled conditions as part of a systematic, close overview of an individual’s health.
Audit		Systematic and documented process for obtaining and evaluating objective evidence and evaluating it objectively to determine the extent of compliance to set criteria.
Authorising officer		The person who is accountable for the risk assessment (sign off). This is likely to be the commander, manager or accountable person if they have delegated the risk assessment to a competent person.
		Where the commander, manager or accountable person has the relevant competence and has undertaken the risk assessment, then the Authorising Officer should be the person who is the next level up in their chain of command.
Automated External Defibrillator (AED)		An AED is a portable electronic machine that can automatically detect the abnormal heart rhythms that cause cardiac arrest and can deliver the shock that is needed to save the life of a person with a rhythm such as ventricular fibrillation (VF).

B

Term	Abbreviation	Definition
Business Manager		A person (in the context of JSP 375, Volume 1, Chapter 12) within their Defence organisation who has been delegated the responsibility for ordering and issuing Specsavers e-vouchers. The Business Manager will have access (or can create an account) to the Specsavers online portal and as such can issue e-vouchers and pay for them using an Electronic Procurement Card (EPC) after obtaining financial approval in line with their local financial processes

C

Term	Abbreviation	Definition
Carcinogen		A substance or preparation (as listed in the schedule 1 of the COSHH ACOP L5) is said to be carcinogenic if after inhalation, ingestion or penetration of the skin occurs, it may induce cancer in humans or increase its incidence.
Change owner		The change owner is the person who initiates, and has overall accountability for the safe implementation of, the change project / programme
Chief Environment and Safety Officer	CESO	Under the Health and Safety at Work etc Act 1974 (HSWA74) companies must seek advice by a competent person to assist them manage Health and Safety within their organisation. For Defence, this role is typically provided by the Chief Environment and Safety Officer (CESO) or an equivalent competent person. CESO’s work within the Defence organisation Safety Centre or equivalent and are required to provide advice on, and assurance of, compliance with Health, Safety and Environmental Protection (HS&EP) legislation and Defence policy. They are responsible for overseeing the development and maintenance of the Defence organisations Safety and Environmental Management System (SEMS).
Child		A child is a category of young person defined as not having yet reached the official age at which they may leave school, just before or after their 16th birthday (this is often referred to as the minimum school leaving age (MSLA))*
		*The oldest pupils of compulsory school age are those born in September and may be as old as 16 years and 10 months in year 11 before they leave school on the last Friday in June.
Chronic effect		Health effect which appears sometime after first exposure to the causative agent. Usually associated with repeated, prolonged exposure.
Cold weather environment		Can be described as an environment where the combination of weather elements, such as low temperatures, wind, precipitation, moisture, and air pressure can create conditions that affect people, equipment and terrain to the degree that it increases the risk to personnel and to the operational output.
Commander		This is generally a military person responsible for planning activities, supervising activities, and making sure that personnel under their area of responsibility are safe. This term refers to a role rather than the rank of Commander, and it can be a permanent or temporary role (for example, lasting for the duration of a training exercise). In parts of Defence this person could be referred to as a ‘responsible person’.
Commanding officer	CO	A Service person in charge of a specific unit, estate (site) or platform.
Community First Responder	CFR	Community First Responders are volunteer members of their community who are trained to respond to emergency calls in conjunction with their local NHS Trust Ambulance Service.
Competence		The combination of training, skills, experience and knowledge that a person has and their ability to apply them to perform a task safely.
		(See www.hse.gov.uk/competence/what-is-competence.htm for information on competence).
Competent person		A person who has the training, skills, experience, and knowledge necessary to perform a task safely and is able to apply them. Other factors, such as attitude and physical ability, can also affect someone’s competence.
		(See www.hse.gov.uk/competence/what-is-competence.htm for information on competence).
Consider		Means it is necessary to think about the topic, but it can be excluded.
Continual improvement		Recurring activity to enhance performance (ISO 45001).
Contractor		A person not directly employed by Defence or a company that is contracted to provide a service or perform a task / activity for Defence. Contractors could be ‘permanent’ (Maintenance Management Organisation (MMO) managers, Mess employees and so on); ‘regular’ (MMO workers, couriers, and so on); or ‘irregular’ (telecoms engineers, contractors locally employed for a specific task and so on).
Control measures		Actions that are taken to reduce or eliminate the risk of exposure to a hazard. They can also reduce the severity of exposure to a hazard. The hierarchy of control measures are ‘elimination, substitution, engineering controls, administrative controls and personal protective equipment (PPE)’.
Control limit		A concentration of asbestos in the atmosphere when measured in accordance with the 1997 WHO recommended method, or by a method giving equivalent results to that method approved by the Health and Safety Executive (HSE), of 0.1 fibres per cubic centimetre of air averaged over a continuous period of 4 hours (CAR Regulation 2).
Corrective action		Action to eliminate the cause of a non-conformity and to prevent reoccurrence.
Crush injury		An injury that occurs when force or pressure is put on a body part. This type of injury most often happens when part of the body is squeezed between two heavy objects.

D

Term	Abbreviation	Definition
Dangerous occurrence		One of a number of specific, reportable adverse events, as defined in the Reporting of Injuries, Diseases and Dangerous Occurrences Regulations (RIDDOR).
Data controller		The entity that determines the purposes, conditions and means of processing personal data. The MOD is the Data Controller for all TLBs, HLBs (and some ALBs).
Data processor		The entity that processes personal data on behalf of a controller. This term refers to those who are not part of the MOD but work for the MOD. They are legally liable for their own data breaches
Data subject		The identified or identifiable living individual to whom personal data relates.
Defence		Refers to the Ministry of Defence (MoD)
Defence acquisition organisations		Defence organisations responsible for the acquisition of infrastructure and equipment. Normally Defence Infrastructure Organisation (DIO) for infrastructure, and Defence Equipment and Support (DE&S)/Submarine Delivery Agency (SDA)/Defence Digital (DD) for equipment. However, could refer to any Defence organisation which takes on infrastructure or equipment acquisition responsibilities, which includes the procurement, support, maintenance and disposal of infrastructure and equipment.
Defence acquisition teams		Individual acquisition teams or individuals within Defence acquisition organisations with acquisition responsibilities.
Defence activity		An activity delivered by a person(s) employed by Defence (military and civilian) or working on behalf of, or under the supervision of Defence (for example, contractors) with the intention of providing benefit to Defence.
Defence alert		The system which enables reporting occurrences via mobile devices.
Defence contractors		Where Defence Contractors undertake work or provide services directly in support of Defence activities, they are to comply with relevant safety legislation, the requirements of the SofS’s Policy Statement and with relevant Defence regulation and policy. This must be prescribed expressly in relevant contractual arrangements. Generally, Defence Contractors cannot benefit from any disapplication, exemption or derogation from statutory requirements granted to Defence where they control activities. There may be exceptions to this which should be specific in contractual arrangements where they occur. Significantly though, Defence Contractors are not exempt from prosecution.
Defence organisation		This refers to Military Commands, Top Level Budgets (TLBs), the Defence Nuclear Organisation (DNO) and Enabling Organisations (EOs) collectively.
Defence personnel		This includes all those working on behalf of Defence, or under the supervision of Defence personnel, military (regular and reserve) and civilian (directly employed or contractors), at home and overseas.
Defence registered asbestos workers		Defence civilian personnel who are employed and / or who previous to the 1987 Control of Asbestos at Work Regulations are / were directly engaged on work with asbestos / ACMs, including those who are or have been subsequently transferred to other areas of work in Defence.
Delivery Duty Holder	DDH	The Delivery Duty Holder (DDH) is an accountable individual who has been appointed by the Senior Duty Holder (SDH) or the Operating Duty Holder (ODH) through a letter of appointment and has formally accepted that appointment.
		The DDH must be able to demonstrate that they have the ability to manage the Risk to Life (RtL) within their defined AoR, have direct access to their Operating Duty Holder and are suitably qualified and experienced to undertake their Duty Holding responsibilities. The DDH should have attended (or be able to demonstrate that appropriate action has been taken to attend) a Defence Safety Authority (DSA) approved Duty Holder Course within 3 months of appointment in post.
Deployment		The movement of personnel or equipment to a place or deployed position to allow military activities to take place (for example, military operations, humanitarian missions, disaster relief).
Derogation		A relaxation or lessening of a legal requirement to allow the MOD to apply the law differently for reasons specified within legislation. The derogation might be subject to certain caveats.
Disapplication		Where specific legislation, or part of it, does not apply to the MOD and this freedom is expressly stated in the legislation.
Diagnosis		A registered medical practitioner’s identification (in writing, where it pertains to an employee) of;
		(a) new symptoms, or
		(b) symptoms which have significantly worsened.
Display screen equipment	DSE	DSE are devices or equipment that have an alphanumeric or graphic display screen and includes display screens, laptops, touch screens and other similar devices.
Display screen equipment (DSE) user		Personnel who normally use display screen equipment (DSE) for continuous or near continuous spells of an hour or more per day.
Domain		Is a term used to describe a functional area, for example the function of flying would be identified as the ‘Aviation’ domain and includes the aviation elements from all of the Military Command, and equally for the ‘Maritime’ and ‘Land’.
DSEAR		Dangerous Substances and Explosive Atmospheres Regulations.
DURALS	DURALS	Defence Unified Reporting and Lessons System.
Dust		Created when solid materials are broken down into fine particles. The smaller the dust, the longer it remains in the air and the easier it is to inhale.
Duty Holding*	DH	Duty Holding must be applied for military activities that the Defence organisation’s most senior leader considers:
		(a) are justified and present a credible and reasonably foreseeable Risk to Life (RtL); and
		(b) the Duty of Care, or other statutory arrangements and / or the control of risks are considered to be inadequate and require enhanced safety management arrangements; or
		(c) are mandated through regulation.
		The SofS for Defence requires that the Defence organisation’s most senior leader is appointed as the Senior Duty Holder (SDH) and is ultimately accountable for RtL for the military activities for which that senior leader has decided to apply Duty Holding.
		*Duty Holding in Defence should not be conflated with ‘duty holding’ as outlined in HSWA74.
Duty Holding construct		In Defence the fundamental elements of Duty Holding management arrangements are that there are three levels of accountable individuals for managing risk where a Duty Holding framework has been applied and they are the: Senior Duty Holder (SDH), Operating Duty Holder (ODH) and Delivery Duty Holder (DDH).
		When appointed, an MOD Duty Holder is responsible for the safe conduct of activities within their AOR by ensuring that RtL are As Low as Reasonably Practicable (ALARP) and Tolerable.
Duty Holder Facing		A Duty Holder Facing organisation is any organisation whose activities and decisions could affect the ability of a Duty Holder to mitigate associated RtL so that they are ALARP and Tolerable. This includes but is not restricted to: providers of support and facilities; Financial / Military Capabilities (Fin/Mil Cap); Defence Equipment and Support (DE&S); Defence Infrastructure Organisation (DIO); and other Defence enabling organisations.
Duty of care	DoC	The legal obligations which ensure the safety or well-being of employees and others who may be affected by the acts or omissions of a person or organisation.

E

Term	Abbreviation	Definition
Electrical Testing		Electrical testing is a visual and physical evaluation of  electrical equipment or systems and must be performed by a competent person, who is suitably qualified and experienced at conducting Electrical Equipment Testing (EET) and using EET equipment.
Electric Vehicle	EV	An Electric Vehicle (EV) is defined as a vehicle that is powered by an electric motor that draws electricity from a battery and is charged from an external source. Usually EVs are powered by Lithium-Ion (Li-ion) batteries and can include some hybrid vehicles (but only those that can be charged from an external source). EVs include but not limited to: electric cars, trucks and coaches.
Elevation		The vertical distance of a point or level, on or affixed to the surface of the earth, measured from sea level. (MLWS / MHWS).
Elevate		The act of raising an issue or concern to a higher level in the chain of command in order to gain authority to continue or the chain of command to accept and take on the risk.
Environment		Surroundings which a system or organisation effects, including air, water, land, natural resources, flora, fauna, and their interrelation with humans (third parties).
Establishment		A geographical Area of Responsibility (AoR) with a fixed boundary, where access to or egress from a place of work can be controlled. A specified permanent office, room, or floor of a lodger. Government property in the form of a building, group of buildings within a site, or group of sites, garrison, or garrisons, base or training area of an estate, facility, range, or exercise area.
Evidence		Information or objective artefacts being offered in support of one or more claims.
Exertional collapse		This is when a person collapses as a direct result of physical exertion normally caused by heat exhaustion, dehydration or underlying health issues.
Exemption		This is a formal written authorisation permitted by legislation to exempt MOD personnel, activities or equipment from specific legislation (or parts of that legislation). An exemption will only be granted by the Secretary of State (SofS) for Defence when it is in the interests of national security or where compliance with the legislation will directly compromise operational capability. Exemptions are generally granted with stipulated conditions.
		Exemptions require the direct authority of SofS, however some are authorised on behalf of the SofS through an exemption committee.
Exposure action value	EAV	This refers to a daily or weekly average noise level threshold, or peak sound pressure. The Legislation defines two EAVs. an upper EAV and a lower EAV.
Exposure limit value	ELV	This refers to the level of daily or weekly personal noise exposure, or of peak sound pressure, which must not be exceeded.

F

Term	Abbreviation	Definition
Facilities		A place, amenity, or piece of equipment provided for a particular purpose.
First aid		The skilled application of accepted principals of treatment on occurrence of an accident/case of sudden illness using facilities or materials available at the time.
First aider		A person who is formally qualified and competent to carry out First Aid at work on adults over 18. This person must have an in-date Emergency First Aid at Work or First Aid at Work qualification.
Frequent		Likely to occur at least several times a year.
Front line command	FLC	The single Service Commands (Air, Land and Navy) responsible for operating, administering, or training its forces outside the requirements of joint operations.
Fume		Created when solid materials (usually metals) vaporise when subjected to high temperatures. The metal vapour rapidly cools and condenses into an extremely small particle, with particle size generally less than one micrometre in diameter.

G

Term	Abbreviation	Definition
Gas		Substance similar to air which becomes airborne at room temperature and, because they are able to diffuse or spread freely, can travel very far, very quickly.
Generic risk assessment		A risk assessment used for activities that share or repeat the same hazards and controls (for example, routine maintenance or cleaning).
Good practice		The standard for controlling risk recognised an authoritative body as satisfying legislative requirements; or meeting recognised industry standards, including continuous improvement when applied to a particular relevant case in an appropriate manner.
Guidance / guidance material		Advice or information aimed at providing a consistent approach to an issue or subject as given by an authority in order to provide additional explanation, assist in application of a regulation or help illustrate meaning. Will assist in compliance as part of good practice.

H

Term	Abbreviation	Definition
Hand arm vibration	HAV	This is exposure to vibration from mainly hand-held, hand-guided and / or hand-fed tools. This includes the vibrations from the various controls and handles of, for example, Armoured Fighting Vehicles (AFVs);
Hand arm vibration syndrome	HAVS	Collectively describes conditions which affect the nerves, blood vessels, muscle and joints of the hand, wrist, and arm. HAVS is a result of vibration causing damage to these areas and can become severely disabling if ignored.
Harm		Any adverse effect on a person, including, physical or psychological injury, or damage to health, the environment or property. It encompasses both short and long-term effects.
Hazard		‘Anything that has the potential to cause harm’. This includes anything that could potentially lead to injury, ill health, damage to property, or environmental damage. (HSE)
Hazard analysis	HA	The process of analysing in detail the hazards and accidents associated with a system.
Hazard identification	Hazard ID	Process of recognising that a Hazard exists and defining its characteristics.
Hazard observation		A specific situation or set of circumstances which did not actually result in a safety occurrence but where the potential for a safety occurrence to occur in the future was identified.
Hazardous substance		A Hazardous Substance is a substance that has the potential to cause harm to human health and / or impact to the environment.
Head of establishment	HoE	Appointed Accountable Person who nominally has control of access and egress for a specified MOD establishment/s and the authority over the ‘safe place’ as their Area of Responsibility. They support those holding responsibility for the activities within that MOD establishment/s, agreeing operating rules and boundaries (incl. station commanders, platform Commanding Officers).
Health		’A state of complete physical, mental, and social well-being and not merely the absence of disease, or infirmity’. (World Health Organisation).
Health Monitoring		Monitoring the health of workers where the effects from an activity or exposure at work are suspected of causing ill health effects, but the association has yet to be fully established.
Health, safety and environmental protection	HS&EP	An umbrella term for the laws, rules, guidance, and processes designed to help protect employees, the public and the environment from harm in the workplace within the Ministry of Defence.
Health and Safety Executive	HSE	Is a non-departmental public body of the United Kingdom. It is the body responsible for the encouragement, regulation and enforcement of workplace health, safety and welfare, and for research into occupational risks in England and Wales and Scotland.
Health Service Support (HSS) Planning		Also known as the medical plan.  The HSS Plan will mitigate risks to life and mission, through Medical Force Preparation measures, prevention of Disease and Non-Battle Injury (DNBI) and timely response to medical incidents / emergencies by the provision of safe and effective care.
Health surveillance		Health surveillance is a systematic process of repeated health checks which are used for identifying ill health or diseases caused by work and for gaining an overview of the health status of the personnel conducting the work. In some cases, it can be used to make sure personnel with pre-existing health conditions can work safely.
Heat illness		Heat illness is a range of illnesses, which includes heat cramps, heat exhaustion and heat stroke. The term ‘heat illness’ describes physical degradation caused by a rise in core body temperature (the temperature of the internal organs).
Heat exhaustion		Heat exhaustion is the body’s response to extreme loss of water and salt, usually through excessive sweating. Left untreated, it can progress to heat stroke.
Heat stroke		Heat stroke is the most serious heat-related illness. The body can no longer control its temperature. The core body temperature rises rapidly and the body cannot cool down. The person may become unresponsive within minutes. It is a medical emergency.
Hierarchy of controls		The control measures perceived to be the most effective and moves down to those considered least effective. It flows as follows:
		- Elimination – Physically remove the hazard
		- Substitution – Replace the hazard
		- Engineering controls – Isolate people from the hazard
		- Administrative controls – Change the way people work
		- Personal protective equipment – Protect the worker with PPE
Hospitalised (‘bedded down’)		Is being admitted to a hospital for more than 24 hours as an inpatient on the recommendation of a suitably qualified medical practitioner and kept there for treatment. The term ‘bedded down’ may be used by the military, when the ability to take an individual to a hospital is not possible, for example onboard a submarine whilst at sea.
Host		The Host is the sponsor of a specific event or work activity, with specified responsibilities, and is also responsible for providing the visitors, visiting workers / contractors with suitable and sufficient information and instruction to safely carry out their activities.

I

Term	Abbreviation	Definition
Identifiable living individual		Means a living individual who can be identified, directly or indirectly, by reference to
		(a) an identifier such as a name an identification number, location data or and online identifier, or
		(b) one or more factors specific to the physical, physiological, genetic, mental, economic, cultural or social identity of the individual.
Incident		An event which causes loss or damage to property, plant or equipment. (See also accident and near miss).
Improbable		Unlikely to occur in 10 years.
Ingestion		Taking in of material via the mouth.
Inhalation		The process or act of breathing in, taking air and sometimes other substances into your lungs.
Inspection		Normally a visual check of the current condition of the electrical equipment, checking for clear signs of damage or other signs of hazardous wear and tear. This does not have to be performed by a qualified electrician but should be conducted by a competent person.
Investigation		Activity carried out by an independent, impartial, professional, and credible safety investigation organisation or team to prevent reoccurrence following an accident or incident. To establish facts by the evaluation of systematic examination, research and evidence gathering. It includes the collection and analysis of evidence, the identification of causal and contributory (aggravating) factors and the making of observations and safety recommendations, as necessary.

K

Term	Abbreviation	Definition
Key health and safety role		An appointment that is required to provide competent specialist advice and guidance for a particular hazard or hazards.
Knowledge, Skills, Experience Behaviours	KSEB (JSP 755)	Knowledge (K) - ‘What you know’. Theoretical or practical understanding of a given subject/area.
		Skills Application (S) - ‘What you can do’. The practical application of a skill through training and/or practice.
		Experience (E) - ‘What you’ve done’. Time spent applying and practising skills in a range of environments/contexts and with varying levels of supervision.
		Behaviours (B) - ‘How you act’. The way you behave in order to add value with your Skill, ensuring a positive impact and role modelling to others.

L

Term	Abbreviation	Definition
Lay Rescuer		A lay rescuer is a non-medical professional, untrained in First Aid at Work who is responding to a First Aid incident.
Legislation		A law or set of laws that have been passed by Parliament. The word is also used to describe the act of making new law.
Legionella		Bacterium Legionella pneumophila (which is more commonly known as Legionella) and related bacteria. Legionella bacteria can cause Legionellosis, the most serious of which is Legionnaires’ disease.
Licensed specialist		An employer, or self-employed person, who has been granted a licence to work with asbestos by Health and Safety Executive (HSE).
Likelihood		Estimate of the probability or frequency of a risk occurring in a specified period of time, based on the description of its cause, event and consequences.
Line of Defence	LOD	The HMT Orange Book describe Lines of Defence (LOD) as the systematic approach that may be used to help clarify the specific roles and responsibilities that are necessary for the effective management of risks within an organisation. When an organisation has properly structured the “three lines model”, and they operate effectively, it should understand how each of the lines contributes to the overall assurance required. Defence use the three Lines of Defence (LOD) approach for ease of delineating roles and responsibilities and to clarify who is responsible for assurance activities at 1LOD, 2LOD and 3LOD.
1st Line of Defence	1LOD	Is for an organisation to identify, assess, own, and manage its own risks. The organisation is responsible to designing, implementing, and maintaining their own control measures, monitoring their adherence, and implementing corrective actions to address deficiencies, for example, within a Defence organisation.
2nd Line of Defence	2LOD	Is for Safety Centres (or equivalent) to operate in this space by setting boundaries, defining standards, policies, procedures, and guidance. Monitor compliance and effectiveness of management systems and identify non-compliances against policy standards, for example, Safety Centres.
3rd Line of Defence	3LOD	Is independent of the Defence organisation, it is an objective evaluation of the adequacy and effectiveness of the framework of governance, risk management and control. It is a proactive evaluation of controls proposed by management and provides advise on potential control strategies and the design of controls. For example, the DSA.
Lone working		A lone worker is a person who undertakes a specific activity unaccompanied or without immediate access to another person for assistance.
Lower exposure action value	LEAV	Refers to the lower of the two levels of daily or weekly personal noise exposure, or peak sound pressure which, if reached or exceed, require specific actions to be taken to reduce risk.

M

Term	Abbreviation	Definition
Maintenance Management Organisation	MMO	An organisation which manages the upkeep and optimal functioning of the physical assets, facilities, and infrastructure of a Defence unit, establishment or site.
Manager		A person responsible for managing or supervising staff, planning activities, and making sure that personnel under their area of responsibility are safe. This could be a permanent or temporary role, and in parts of Defence this person could be referred to as a ‘line manager’, a ‘responsible person’ or a ‘delivery manager’.
Management system		A system to establish policy and objectives or to achieve those objectives.
Maintenance		The combination of all technical and administrative actions, including supervision actions, inspection, testing, servicing, and classification as to serviceability intended to retain an item in a state in which it can perform a required function.
Medical Record		Medical records are kept as ‘medical in confidence’ by the occupational health professional responsible for conducting the Health Surveillance or Health Monitoring. They may include confidential clinical notes, test results and more general information about a workers’ health.
Medical Surveillance		Where Medical Surveillance is required, you must use a competent occupational health doctor appointed by HSE, called an ‘appointed doctor.’
Memorandum of understanding	MOU	A nonbinding agreement that states each party’s intentions.
Mental Health Fitness Representative	MHFR	Someone who provides initial support, encouragement, and signposting to someone who is experiencing poor mental health, to the support available to them. Mental Health Fitness Representatives can also play a significant role in reducing stigma and promoting positive mental health in the workplace.
Military		The word ‘military’ covers all the Services, including Regular, Reserve and Cadet Forces.
Military command		This refers to the Front-Line Commands and UK Strategic Command.
Mist		Tiny liquid droplets that are formed from liquid materials by atomisation and condensation processes such as spraying.  Many mists are a combination of several hazardous ingredients.
Mitigate (Mitigation)		An activity of putting control measures in place that are expected to reduce the likelihood and severity of harm from a risk event.
MOD policy		A rule made to set out direction, principles and courses of action that apply to the whole of the MOD. Compliance is mandatory. Internal MOD principles and standards that requires compliance in relation to MOD operations and by MOD personnel.
Must		That the action is a compulsory requirement within Defence.
Mutagenic		A substance is said to be mutagenic if, after inhalation, ingestion, or penetration of the skin, it may involve a risk of hereditable genetic defects.
MySafety		MySafety is a web-based application to support the reporting and management of safety and environmental occurrences, incidents, near-misses, investigations and recommendations.

N

Term	Abbreviation	Definition
Near miss		An event that had the potential to cause injury, ill health or death to a person(s) or damage to property, plant or equipment, but no actual harm or damage occurred.
Noise		Is ‘any audible sound’ whether it is wanted or not. Noise is considered to have the same definition as ‘sound’ which refers to wanted noise, for example, the music from a band.
Noise exposure		This refers to the combination of the time period and the average amplitude of the noise over that time period (‘how loud’ and ‘how long exposed’).
Notification		The urgent act of immediately informing those required of a serious safety occurrence - usually by telephone.
Noise risk assessment		Refers to a documented assessment of the risk that noise poses to personnel.

O

Term	Abbreviation	Definition
Occasional		Likely to occur one or more times per year.
Occupational health professional		Normally a doctor or nurse who is qualified in occupational health matters or who has undergone specific training, for example, a nurse administering a hearing test.
Occurrence		Refers to the terms Accident / Incident, Near Miss, Unsafe Act, Unsafe Condition and Dangerous Occurrence.
Operation		A sequence of coordinated actions with a defined military purpose and authorised by a formal order.
Operating Duty Holder	ODH	The Operating Duty Holder (ODH) is an accountable individual who has been appointed by the Senior Duty Holder (SDH) through a letter of appointment and has formally accepted that appointment. The ODH must be able to demonstrate that they have the ability to manage the RtL within their defined AoR, have direct access to their Senior Duty Holder and are suitably qualified and experienced to undertake their Duty Holding responsibilities. The ODH should have attended (or be able to demonstrate that appropriate action has been taken to attend) a DSA approved Duty Holder Course within 3 months of appointment in post.
		*This includes the financial authority to prioritise resource within their AoR to deliver safe outcomes.
Operational imperative		A set of circumstances tolerated by an Operational Commander that requires Force Elements (personnel and equipment) to operate outside their defined operating envelope that are considered essential to achieve an operational objective.
Operational requirement		The standards to be demonstrated during operations.
Organisation		Company, operation, firm, enterprise, institution or associations, or part thereof, whether incorporated or not, public, or private, that has its own functions and administration.
		For organisations with more than one operating unit, a single operating unit may be defined as an organisation.
Operational safe system of work	OSSW	A method of work which puts in place control measures arising from a risk assessment, in order to eliminate identified hazards (where possible) and complete the work with minimum risk taking into consideration the realities of operations.
Overseas		In or to a foreign country outside UK territorial waters.

P

Term	Abbreviation	Definition
Peak sound pressure		Refers to the maximum sound pressure to which personnel are exposed.
Permit to Work		The permit to work is a documented procedure that authorises certain people to carry out specific work within a specified time frame. It sets out the precautions required to complete the work safely, based on a risk assessment. It describes what work will be done and how it will be done.
Personal data		Any information relating to an identified or identifiable living individual.
Personal Health Record		A legal record of the outcome of Health Surveillance and or Health Monitoring. A health record does not contain any ‘medical in confidence’ information.
Personal protective equipment	PPE	All equipment (including clothing) which is intended to be worn or held by a person at work, and which protects that person against one or more risks to that person’s health, and any addition or accessory designed to meet that objective.
Policy		A course or principle of action to be adopted.
Portable Electronic Devices (PEDs)		Devices for example, laptops, mobile phones tablets and so on, that allow you to undertake familiar desktop applications whilst on the move.
Pollution		Means the release of substances which can cause harm to man or any other living organisms supported by the environment.
Powered Transporters		A personal mode of transport that is powered by an electric motor that draws electricity from a battery and is charged from an external source. Powered transporters are often powered by Lithium-Ion (Li-ion) batteries and can include e-bikes, e-scooters, e-hoverboards, e-golf carts, e-wheelchairs, e-mobility aids and so on.
Principles		Fundamental truths or doctrines of law; comprehensive rules or doctrines which furnish a basis or origin for others; settled rules of action, procedure, or legal determination.
Processing (personal data)		Any operation performed on personal data, whether or not by automated means, including collection, use, recording, and so on.
Probability		A numerical description of the chance of a risk event occurring, usually described as a percentile figure. Note this is different to likelihood; likelihood is a broader term that encompasses probability but also includes qualitative descriptions of the chance of a risk event occurring.
Procurement or acquisition teams and local procurement		Those responsible for activities which relate to the ordering and receiving of goods, materials, supplies, equipment, and services. This may include sourcing, negotiation, contracting, the monitoring of supplier’s performance and making sure of compliance with operational protocols.
PULHEEMS assessment		A system of grading the fitness of personnel.

R

Term	Abbreviation	Definition
Reasonably practicable		Is a narrower term than ‘physically possible’ … a computation must be made by the owner in which the quantum of risk is placed on one scale and the sacrifice involved in the measures necessary for averting the risk (whether in money, time or trouble) is placed in the other, and that, if it be shown that there is a gross disproportion between them – the risk being insignificant in relation to the sacrifice – the defendants discharge the onus on them. (Definition set by Court of Appeal in Edwards vs National Coal Board [1949]) (HSE).
Regular		Following a pattern, especially with the same time or space in between each thing and the next. Done or happening often.
Regulation		A ‘rule or authoritative direction’ having the effect of law, placing restriction on another organisation, or defining overarching mandatory activities or conditions that are to be met without exception. The act of regulating is enforcement of compliance with a rule or authoritative direction prescribed by those delegated such authority.
Remote (timeframe)		Likely to occur one or more times in 10 years.
Remote working		Personnel habitually working at locations that are remote from their management chain of command and parent organisation, whether it be working on the move, working from home, or working from satellite locations.
Reporting		The routine act of recording the details of all occurrences, regardless of whether they are notifiable, often using information technology management systems for example, MySafety and ASIMS.
Reporting of Injuries, Diseases and Dangerous Occurrences Regulations	RIDDOR	The Reporting of Injuries, Diseases and Dangerous Occurrences Regulations 2013 and Northern Ireland 1997.
Residual risk		The level of risk remaining after control measures have been applied.
Respiratory protective equipment	RPE	A particular type of Personal Protective Equipment (PPE), used to protect the individual wearer against the inhalation of hazardous substances in the workplace air.
Restricted Material		Is one that has any legislative control on the importing, manufacture, use or placing on the market of the material. In some cases, the material can continue to be used for specific uses or where the substance is below a certain concentration in a mixture or article.
Risk (safety risk)		Combination of the likelihood of harm (how often) and the severity of that harm (how bad).
Risk assessment	RA	A systematic process of identifying hazards and evaluating any risks associated with those hazards.
Risk management	RM	Process that encompasses systematic hazard identification; risk assessment; hazard risk matrix; risk reduction and risk monitoring, evaluation, and review.
Risk to Life	RtL	Is where the outcome of an activity has a high probability of resulting in a fatality.
People should only be exposed to risk of harm where some defined benefit is expected and where the risks are adequately controlled.
Routine work		Work which a person might reasonably be expected to do, either under that person’s contract of employment, or, if there is no such contract, in the course of that person’s work.

S

Term	Abbreviation	Definition
Safe		“Not in danger or likely to be harmed”. (Cambridge Dictionary definition).
Safety (at work)		The process of protecting personnel, contractors, visitors and others from injury and illness on the Defence estate or whilst conducting Defence activities.
Safety assessment	SA	A systematic, comprehensive evaluation to identify all safety features of the system design, including hardware and software, and to identify all hazards and safety factors cross-DLOD that may be present in, or required for, the system being acquired, and then operated, including specific procedural controls and precautions that are to be followed. The Safety Assessment (SA) contains the structured argument that the system is safe for its intended use and that a specific DLOD has been considered in the context of the overarching Air System Safety Case.
Safety case	SC	A structured argument, supported by a body of evidence that provides a compelling, comprehensible, and valid case that a system is safe for a given application in a given operating environment.
Safety Centre		The Safety Centre or equivalent is the team established in each Defence organisation to support the Safety Director/ Head of Safety to implement the strategic direction that they have set for Health, Safety and Environmental Protection (HS&EP) within their organisation. The Safety Centre is made up of individuals with the relevant safety and environmental, knowledge, skills application, experience and behaviours (KSEB) to support the Safety Director/ Head of Safety to deliver the Defence organisations Safety and Environmental Management System (SEMS) and to oversee compliance with Defence HS&EP policy and regulations. They are also the Defence organisations point of contact for liaising with statutory and Defence Regulators and are the first point of contact for all safety and environmental related issues.
Safety-critical role		A safety-critical role refers to a position with formal responsibility for safety governance, oversight, or assurance, or which provides competent advice to leaders in their Defence organisation where their absence or failure of their responsibilities in post could result in legal non-compliance, regulatory breach, or unacceptable risk to people, assets, or reputation. These roles typically:
		Hold delegated responsibility for safety under legal frameworks or Defence safety management system.
		Influence or approve strategic safety decisions, policies, and risk tolerances.
		Ensure organisational compliance with safety legislation and standards.
		Are named accountable persons in safety governance structures.
Safety Data Sheet	SDS	An important document that contains the information necessary for the safe supply, handling, and use of hazardous substances and should contain the information necessary to undertake a risk assessment as required by COSHH. The term Material Safety Data Sheet may still be found in some references and documentation however, following the adoption of the Globally Harmonised System (GHS) Safety Data Sheets (SDS) is the current and legally recognised term in the UK and Globally.
Safety & environment management system	SEMS	The organisational structure, processes, procedures, and methodologies that enable the direction and control the activities necessary to meet safety or environmental requirements and policy objectives.
Safe equipment		This is equipment that has the necessary safety documents and, for more complex equipment, a safety case. If the equipment does not have a safety case, any hazards associated with the equipment should be included in the activity-specific risk assessment.
Safe person		This is a person who has been given the appropriate information, training, instructions, and supervision to enable them to carry out a specific activity.
Safe place		This relates to the space personnel will be in when performing an activity, including any surrounding areas and areas where other people might be affected by the activity. The activity-specific risk assessment should consider the proposed use of the space and any control measures put in place.
Safe practices		This covers the safe conduct of any activity. Safe practices are usually written procedures detailing how to perform an activity with minimum risk to personnel, equipment, materials, and the environment. These written methods should be risk assessed to make sure the risk of harm or damage remains ALARP and tolerable.
Safe system of training	SST	Part of a safe system of work, which sets the conditions under which training must be carried out, making sure that personnel who are not yet competent receive appropriate information, instruction, and supervision.
Safe system of work	SSW	A method of work which puts in place control measures arising from a risk assessment, in order to eliminate identified hazards (where possible) and complete the work with minimum risk.
Secretary of State for Defence	SofS	A Member of Parliament within Her Majesty’s Government and head of the Ministry of Defence  who has overall responsibility for the business of the department. The office is a Cabinet level position.
‘Sen’ notation		Substances assigned this notation are capable of causing occupational asthma. Risk phrases used include R42 or R42 / 43.
Senior Duty Holder	SDH	A Defence organisation’s most senior leader is appointed as the Senior Duty Holder (SDH) and is ultimately accountable for RtL for the military activities for which that senior leader has decided to apply Duty Holding, this is in addition to their legal HS&EP responsibilities. The SDH is formally appointed by letter from the SofS and has right of access to the SofS.
		The SDH will be personally accountable for ensuring that an effective SMS is resourced and implemented for any activity where a Duty Holding framework has been applied. If a SDH considers that a risk from a military activity cannot be mitigated so that it is ALARP and tolerable they have the delegated authority to stop those activities and where necessary to inform the SofS.
‘Sk’ notation		Substances assigned an ‘Sk’ notation in EH40 indicate the ability of such substances to be absorbed through intact skin. There is concern that the substance is absorbed and transported to other parts of the body (systemic toxicity).
Senior responsible owner	SRO	The Senior Responsible Owner (SRO) is the formally appointed individual with overall accountability for ensuring that a programme is governed effectively, meets its objectives and delivers the projected benefits.
Severity		A measure of the degree of harm.
Shall		Shall is the executive verb used in statute to state that the regulated person has no choice but to do what is stated in the legislation.
(Note ‘shall’ is no longer used in Defence Safety Policy instead the term ‘must’ is used, where an action is a compulsory requirement within Defence.)
Should		Means that the action is not a compulsory requirement but is a recommendation of good practice to comply with the policy.
SofS’s Policy statement		Secretary of State for Defence policy statement of intent for health safety and environmental protection.
So far as is reasonably practicable	SFAIRP	Legal phrase used in Health and Safety at Work Act etc 1974, which is alternatively referred to as ALARP, the degree of risk where the trouble, time and money needed to reduce that risk starts to become disproportional to the derived benefit.
Statute		Law made by the UK Parliament. Acts are primary legislation and Regulations are secondary legislation as they depend on other legislative authority.
Stressor		An activity, event or other factors that has the potential to cause stress
Subject matter expert	SME	The individual or organisation most directly concerned with a specific subject. Whilst the sponsor of the subject remains ultimately accountable for the subject, an SME is responsible for the completeness and technical accuracy of the information they provide and for notifying the sponsor when the information changes or requires amendment. The SME may appoint additional SMEs to assist in providing information.
Suitably Qualified and Experienced Person	SQEP	An individual who has received training commensurate with their duties, is qualified, current and has experience in the required task.

T

Term	Abbreviation	Definition
Taken into account		Means it is necessary to think about the topic but it cannot be excluded.
Teratogenic		A substance is said to be teratogenic if, after inhalation, ingestion, or penetration of the skin, it may involve a risk of subsequent non-hereditable birth defects in offspring.
Time weighted average	TWA	This term applies to exposure to airborne concentrations of substances averaged over a time period. The two periods used are: long term (8 hours) and short term (15 minutes). Short term exposure limits (STEL) are set to help prevent effects, such as eye irritation, which may occur after exposures of a few minutes.
Timely		Happening at exactly the right time.
Tolerable (risk)		A level of risk that we are willing to accept in order to perform an activity or achieve an outcome. A tolerable risk is one that is considered to be worth taking, if it has been evaluated and is being managed.
Training imperative		The standards to be demonstrated during training, and when preparing personnel and equipment for deployment, to enable personnel to meet the operational requirements.

U

Term	Abbreviation	Definition
Unsafe act		Any act that deviates from a generally recognised safe way of doing a task and increases the likelihood of an accident / incident.
Unsafe condition		Fundamentally associated with the quality of the working environment and may be defined as ‘any conditions that may cause or contribute to an accident / incident or occupational illness / disease’.
Upper exposure action value	UEAV	This refers to the higher of the two levels of daily (or weekly) personal noise exposure, or of peak sound pressure which, if reached or exceeded, require specific actions to be taken to reduce risk. These are in addition to the actions taken if the lower EAV is exceeded.

V

Term	Abbreviation	Definition
Vapour		Gaseous state of substances that are either liquids or solids at room temperature. They are formed when solids or liquids evaporate.
Vibration		The mechanical oscillations of an object about an equilibrium point.
Visitor		Non-workers who may visit the Defence establishment which may include members of the public for open days, mess events, graduations and so on; volunteers for example assisting in a site museum, or taking part in conservation activities and so on; emergency services; or regulatory bodies for example Health and Safety Executive or Environment Agency and so on.

W

Term	Abbreviation	Definition
Waste		Means any substance or object which the holder discards or intends to or is required to discard.
Welfare		The availability of facilities and presence of conditions required for reasonably comfortable, healthy, and secure living.
Wet bulb globe temperature	WBGT	A combined estimate of the effect of temperature, humidity, wind speed (wind chill), and visible and infrared radiation (usually sunlight) on humans. A WBGT can be provided as a forecast or a current reading from a QuestTemp 34 (QT34) monitor.
Whole body vibration	WBV	This is exposure to vibration usually transmitted to the whole body from a supporting surface, seat, or a platform, for example part of a vehicle, ship, boat, or aircraft.
Workplace exposure limits	WEL	Are exposure limits set by the HSE under COSHH in order to help protect the health of workers. They are concentrations of hazardous substances in the air averaged over a specified period of time referred to as a time weighted average (TWA).
Work related		Having a connection with activities undertaken in the course of normal duties. The fact that there is an accident at work premises does not, in itself, mean that the accident is work-related – the work activity itself must contribute to the accident.
Work / rest table		A table giving maximum durations of continuous exercise and alternative work / rest schedules for a four-hour period. The figures are based on work rate, dress and WBGT reading. Different tables are used for acclimatised personnel and personnel who are not acclimatised.
Workstation		An assembly comprising of,
		(1) display screen equipment (whether provided with software determining the interface between the equipment and its operator or user, a keyboard, a mouse, or any other input device),
		(2) any optional accessories to the display screen equipment,
		(3) any disk drive, telephone, modem, printer, document holder, work chair, work desk, work surface or other item peripheral to the display screen equipment, and
		(4) the immediate work environment around the display screen equipment.

Y

Term	Abbreviation	Definition
Young person		A young person is anyone under 18 years of age.