Healthcare ventilation: what HTM 03-01 requires

What is HTM 03-01 and what does it cover?

HTM 03-01 is NHS England's Health Technical Memorandum on specialised ventilation for healthcare premises. NHS England's publication page says the documents "give comprehensive advice and guidance on the legal requirements, design implications, maintenance and operation of specialised ventilation in healthcare premises providing acute care". The 2021 edition was first published on 22 June 2021 and replaced the 2007 HTM 03-01, HTM 2025 (1994) and DV4 (1983). It has two parts: Part A, Design and Validation, and Part B, Operational Management and Performance Verification.

NHS England's addendum on HEPA devices describes it as "a robust standard for ventilation of higher risk clinical spaces based on high air change rates using outdoor air to continually flush indoor spaces". Scotland publishes its own SHTM 03-01, also in Parts A and B. This page does not reproduce the room-by-room air change rates, pressure regimes or filter grades in Part A, because those figures should be read from the current edition of the document itself.

Does HTM 03-01 apply to a GP surgery, dental practice or clinic?

It depends on a risk assessment. The NHS England page says that "in other types of healthcare a risk assessment of the nature of the treatment being delivered, condition of the patients and intensity of use needs to be undertaken by those responsible for the facility in order to determine the extent to which this guidance will be applicable". The addendum on HEPA devices, which "forms an addendum to" the memorandum, "applies to all healthcare spaces with ventilation requirements" and names "primary care and dental suites" among the settings where poor ventilation raises infection risk.

Setting	How HTM 03-01 reaches it
Acute hospital	Applies as the standard: Part A for new installations and major refurbishments, Part B for running them
GP surgery, dental practice, clinic	The responsible person's risk assessment decides how much to follow
Any registered provider in England	Legal duties on premises and infection control apply whatever the document says

The legal hooks for providers registered in England are short. Regulation 15 requires premises and equipment to be "suitable for the purpose for which they are being used". Regulation 12 requires "assessing the risk of, and preventing, detecting and controlling the spread of, infections, including those that are health care associated". A written ventilation risk assessment answers both.

What does Part A ask for in new and refurbished systems?

NHS England says Part A "applies to new installations and major refurbishments of existing installations and should be considered as the standard to be achieved". A brief for a new air handling unit in an acute setting should therefore cite Part A, ask for the design to be validated, and keep the validation record. The guides to air handling units, filter grades and steam and adiabatic humidification cover components found in these systems.

Two points from the addendum help a buyer who is not an engineer. HEPA filters "have a filter efficiency of at least 99.95% (H13 filter) or 99.995% (H14 filter)" for the most penetrating particle size. And local air cleaners supplement ventilation without replacing it: NHS England's worked example is a treatment room with 6 air changes an hour that "could achieve the equivalent of 10 ACH" with a filtration unit adding 4 equivalent changes. It also states that "air cleaners should not be used as a reason to reduce ventilation".

Part B: who looks after ventilation after handover?

Part B covers operational management and performance verification. The addendum describes the local Ventilation Safety Group as "a group of individuals with recognised expertise in the design and operation of ventilation devices and systems responsible for the governance of the device deployments, as defined in HTM 03-01". It includes competent persons, "including the Authorising Engineer (Ventilation)", with representatives from infection prevention and control, nursing, and clinical engineering or estates.

A single-site practice will not have that structure, but it needs the same functions: a named competent person, a maintenance schedule, and records that show the system still performs. The addendum lists why systems fall short of the standard: "age, condition of air handling plant, lack of maintenance or other design or operational issues". The AHU maintenance checklist covers the routine tasks.

Clinics that add HEPA air cleaners take on their own routine. The addendum says "all devices should undergo at least annual checks to verify their continuing performance", and that "filters should not be changed in clinical areas due to the possible hazards of microorganism and dust dispersal during the procedure".

When do the general Building Regulations rules apply instead?

HTM 03-01 is guidance. For building work in England, GOV.UK says the ventilation requirements of the Building Regulations are "set out in Part F of Schedule 1 to the Building Regulations", and Approved Document F: Volume 2 applies to buildings other than dwellings. Both can apply to the same project: the Building Regulations apply to the building work, while the memorandum is the benchmark for acute care and, where the risk assessment points to it, for other settings. For staff, HSE quotes regulation 6: every enclosed workplace must be ventilated by "a sufficient quantity of fresh or purified air". The commercial ventilation requirements guide separates the two duties.

Water safety runs alongside. HSE says hot water should reach 50°C (55°C in healthcare premises) within 1 minute at outlets, and that in an acute hospital "all aspects of the guidance may need to be followed" while in other settings "a local risk assessment will help determine which aspects of the guidance are relevant".

How should a clinic owner decide what to do?

1. List rooms by procedure and patient group.
2. Record the risk assessment the NHS England page expects, room by room.
3. Compare existing ventilation with the standard, noting age, plant condition and maintenance history.
4. Commission a competent ventilation engineer to measure and report.
5. Keep validation and maintenance records together.

The commercial ventilation cost page explains what drives a system's price, and the ventilation and MVHR page covers system types. You can send an enquiry through the form to ask for quotes against your own room list.

Sources

• Health Technical Memorandum 03-01: Specialised ventilation for healthcare premises, NHS England, updated 26 January 2024, checked 22 October 2026
• NHS Estates Technical Bulletin NETB 2023/01A: application of HEPA filter devices for air cleaning in healthcare spaces, NHS England, updated 2 October 2023, checked 22 October 2026
• Ventilation for Healthcare Premises (SHTM 03-01), NHS National Services Scotland, checked 22 October 2026
• Health and Social Care Act 2008 (Regulated Activities) Regulations 2014, regulation 15, legislation.gov.uk, checked 22 October 2026
• Health and Social Care Act 2008 (Regulated Activities) Regulations 2014, regulation 12, legislation.gov.uk, checked 22 October 2026
• Ventilation: Approved Document F, MHCLG, GOV.UK, updated 15 June 2022, checked 22 October 2026
• Ventilation in the workplace: overview, HSE, checked 22 October 2026
• Hot and cold water systems (legionella), HSE, checked 22 October 2026

Frequently asked questions

Is HTM 03-01 a legal requirement?

It is NHS England guidance. The publication page describes it as advice and guidance on the legal requirements, and says Part A should be considered the standard to be achieved for new installations and major refurbishments. Legal duties come from regulations, including regulations 12 and 15 for registered providers in England and regulation 6 of the Workplace Regulations for staff.

Can portable air cleaners replace mechanical ventilation in a clinic room?

No. NHS England says HEPA air cleaners are one option for improving and supplementing ventilation, and that they should not be used as a reason to reduce it. A scheme that adds them needs a risk assessment by competent persons, including infection prevention and control.

Does Scotland use the same document?

No. National Services Scotland publishes Scottish Health Technical Memorandum 03-01, in Parts A and B covering design, validation, operational management and performance verification. For Wales and Northern Ireland, check the health body that applies to the premises.