Indoor air quality
The air inside a building is the air your staff and customers breathe all day. Here is why indoor air quality is a health, comfort and cost issue, and what governs it.
Most people in the UK spend the overwhelming majority of their lives indoors, and a large share of that time is at work. The air inside a commercial building is therefore not a background detail but the air that staff, customers and visitors actually breathe for eight or more hours a day. When it is good, nobody notices; when it is poor, it quietly costs a business in health, comfort and concentration.
Indoor air quality, or IAQ, describes how clean and healthy the air inside a building is: how much fresh outdoor air is reaching people, and how well pollutants are being diluted or removed. Studies routinely find that people spend around ninety per cent of their time indoors, and that indoor pollutant levels can be higher than those outside. Offices, shops, gyms, care homes and kitchens all generate their own mix of carbon dioxide from breathing, moisture, odours, dust and chemical vapours, and it is the ventilation system, working properly, that keeps that mix within healthy limits. Poor IAQ rarely announces itself; it shows up as tiredness, headaches and a vague sense that a room is stuffy.
What sits in the air
Indoor air is a moving target. Carbon dioxide builds up wherever people gather, and is widely used as a marker for how well a space is ventilated. Volatile organic compounds, or VOCs, come off furniture, paint, cleaning products and printers. Fine particulate matter drifts in from traffic outside or is generated by cooking and activity inside. Moisture from people, kettles and washing raises humidity and, left unchecked, feeds mould. Add formaldehyde from some building materials and the occasional combustion by-product, and it becomes clear why simply sealing a building tight for energy savings, without matching ventilation, tends to make the air worse rather than better.
The framework that governs this in the UK is layered. The Building Regulations Approved Document F sets ventilation provisions for new and altered buildings, while CIBSE guidance such as Guide A and KS17 gives the design rates that good practice follows. For existing workplaces, the Workplace (Health, Safety and Welfare) Regulations 1992 place a plain duty on every employer to provide enough fresh or purified air in enclosed work areas. These duties sit alongside, but are separate from, the COSHH controls that deal with specific hazardous substances and local exhaust ventilation. General IAQ is about the everyday air everyone shares, not just about a single identified contaminant.
None of this is only a health question. Ventilation typically accounts for a substantial share of a building's heat loss, often cited at around thirty per cent in commercial premises, so the way a building is aired is also an energy and cost question. The goal is not maximum ventilation at any price but the right amount of clean air delivered efficiently, which is exactly why design rates, controls and maintenance all matter together rather than in isolation.
Why operators should care
Good indoor air is quietly commercial. Staff in well-ventilated spaces report fewer headaches and less fatigue, concentrate better and take fewer sick days, while customers simply stay longer in premises that feel fresh rather than stuffy. Poor air does the reverse, and in hospitality it compounds with heat and grease: a hot, badly ventilated kitchen carries a real hidden cost in comfort, safety and staff turnover. Treating IAQ as part of how a business performs, rather than an afterthought, tends to pay back in ways that are felt long before they are measured.
Keeping the system honest
A ventilation system can only deliver good air if the ductwork carrying that air is clean. Over time, ducts accumulate dust, grease and debris that restrict airflow and can harbour contaminants, so a system that looks adequate on paper may be moving far less fresh air than intended. This is why planned duct cleaning matters, and why matching fresh-air supply to actual need, as with demand-controlled ventilation, only works when the ducts behind it are clean. Clean ducts are the difference between a system that promises fresh air and one that delivers it.
Questions
Because people spend most of their day indoors, the air inside directly affects health, comfort and concentration. Good indoor air quality reduces headaches, fatigue and sick days, while poor air quality quietly harms wellbeing and productivity across staff and visitors alike.
Common ones include carbon dioxide from occupants, volatile organic compounds from furniture, paint and cleaning products, fine particulate matter from traffic and activity, excess moisture leading to mould, and formaldehyde from some materials. Ventilation dilutes and removes this mix.
The Building Regulations Approved Document F sets ventilation provisions for buildings, CIBSE guidance gives design rates, and the Workplace (Health, Safety and Welfare) Regulations 1992 require employers to provide enough fresh or purified air in enclosed workspaces.
At the levels found in most buildings, CO2 is not directly harmful, but it is a useful proxy for ventilation. Rising CO2 shows fresh air is not keeping pace with occupancy, and other pollutants are likely building up alongside it.
Ductwork accumulates dust, grease and debris that restrict airflow and can harbour contaminants. Planned cleaning to recognised cleanliness standards restores proper airflow, so the ventilation system actually delivers the volume of fresh air it was designed to provide.
Phoenix Duct Clean · by the numbers
Phoenix cleans and certifies commercial ductwork and extraction systems across the region, so your ventilation delivers the fresh air it should. Talk to us about a survey.