Indoor air quality

Healthcare workers spend a lot of time indoors, so it’s important to have clean, fresh air.

Poor indoor air quality (IAQ) can happen when:

• there isn’t enough ventilation
• the air contains harmful substances, such as chemicals or germs

Poor air quality can worsen illness, cause respiratory issues, or spread infections.

To help managers check and improve the air quality in their workplaces, the Health and Safety Authority (HSA) has a Code of Practice for Indoor Air Quality.

This Code helps protect employees' health through practical measures and compliance with legal requirements.

Ventilation

Ventilation means bringing fresh air in from outside and letting stale air move out. This can happen naturally (such as opening windows), by using machines (such as fans or air systems), or by using both together.

Ventilation in healthcare

Good ventilation is essential in healthcare settings.

It helps to:

• reduce airborne germs
• lower the risk of infection
• keep patients and staff comfortable

The type of ventilation system used depends on the facility’s needs. Systems can be simple, intermediate, or complex:

• Simple ventilation: involves natural airflow through windows, vents, or other openings. It's often used in low-risk areas such as offices or waiting rooms.
• Intermediate ventilation: involves mechanical systems such as fans or basic heating ventilation air conditioning (HVAC) systems. These systems can be used in general patient rooms, outpatient clinics, or staff areas.
• Complex ventilation: involves advanced HVAC systems with HEPA filtration, pressure controls, and air monitoring. These systems can be used in critical zones like operating theatres, isolation rooms and intensive care units.

Each type of ventilation helps keep indoor spaces safe and healthy. Choosing the right system depends on the clinical function, risk level, and regulatory requirements for the space.

Mechanical ventilation systems must be properly maintained and cleaned regularly to prevent contaminant build-up.

Risk assessment

You should complete a risk assessment to assess the indoor air quality.

Managers should identify areas where the air quality might be poor.

These areas might include:

• rooms with no ventilation (mechanical or natural)
• spaces that feel stuffy or have bad smells, which can mean poor air exchange
• areas where mechanical systems only recirculate air instead of bringing in fresh air
• complex ventilation systems, such as those in isolation rooms, that need expert inspection

Who should complete the IAQ risk assessment?

The person responsible for carrying out an indoor air quality (IAQ) risk assessment depends on the complexity of the ventilation system.

Simple systems: in areas with simple ventilation, line managers or designated staff can complete the IAQ risk assessment. See IAQ Risk Assessment Worked Example (PDF, 285 KB, 3 pages).

Intermediate and complex systems: in areas with more advanced ventilation, the line manager should do the IAQ risk assessment. Managers should get technical input from local maintenance managers, or others that might include:

• building management system contractors, if needed
• occupational hygienist
• infection prevention and control specialists
• HVAC engineers

To identify who should carry out the assessment and what factors to consider based on the type of ventilation system, refer to the Indoor Air Quality Assessments - A Quick Guide (PDF, 870 KB, 1 page).

In more complex healthcare areas, such as negative pressure rooms or operating theatres, specific ventilation requirements apply. Further information is available in Health Technical Memorandum 03-01: Specialised Ventilation for Healthcare Premises. This guide provides detailed advice on design, installation, and operation of specialised building and engineering systems.

Improving ventilation

Practical tips to improve ventilation:

Natural ventilation

• open windows and vents when safe and appropriate
• open windows or vents on opposite sides to create airflow
• report bad smells, draughts, condensation, or humidity issues to maintenance
• keep the area clean to prevent dust and mould growth

Mechanical ventilation

• operate ventilation systems as designed
• carry out regular maintenance to keep them working properly
• maximise fresh air intake and minimise reusing unfiltered air
• use the correct filters and replace them regularly
• keep the system clean - remove dust, prevent mould growth, and make sure vents aren’t blocked

Estates

Estates teams have an important technical role in maintaining healthcare environments. They are not usually responsible for conducting routine IAQ assessments. They are typically involved only when issues arise that requires their engineering expertise.

When to involve Estates

Estates teams should be contacted in the following situations:

• ongoing or widespread IAQ complaints that affect several areas or staff members
• confirmed problems with HVAC systems or ventilation performance
• specialist investigations based on local IAQ assessments that show engineering-related issues

For day-to-day IAQ monitoring and assessments, contact local maintenance or service managers.

Related documents

Generic Risk Assessment Form (Word, 37 KB, 2 pages)

Generick Risk Assessment Fillable Form Template (Word, 59 KB, 2 pages)

IAQ Risk Assessment Worked Example (PDF, 285 KB, 3 pages)

Indoor Air Quality Assessments - A Quick Guide (PDF, 870 KB, 1 page)