The air we breathe indoors via ventilation systems, such as air conditioning, is channelled via ducts. Over time, as the air travels through the ductwork, a build-up of bacteria, dust, debris and other indoor pollutants can occur. The longer it remains, the more it will affect the quality of the air you are breathing in and could result in serious health problems.

To avoid this happening, and to comply with obligations to provide a healthy and safe working environment, it’s important to ensure that duct cleaning is carried out regularly. Let’s look at this in more detail.

What is ductwork?

The term ductwork refers to the series of tunnels or tubes – usually made from a synthetic material, like plastic, or metal – that are connected to transport air in an HVAC (heating, ventilation and air conditioning) system in a building.

The air in the building is sucked into the ducts, pushed through a unit which either cools or heats the air, and the clean air travels back through the ducts into the rooms, such as living space or offices.

Why does it need to be cleaned regularly?

As the air is sucked into the ductwork, it brings with it a variety of indoor pollutants, such as dust particles, bacteria that can carry viruses, VOCs (volatile organic compounds), and pesticides and if the ductwork is quite old, there may well be debris in the ductwork as well.

These pollutants come from a variety of sources indoors, including air fresheners, wood-burning stoves and open fires, and tobacco smoke. Over time, the pollutants attach to the air particles and are channelled back into the indoor environment, i.e. the air that you breathe indoors. They can cause health problems from headaches, wheezing, coughing and nausea to more serious issues, like respiratory infections, lung cancer and heart disease.

By making sure the ductwork is cleaned on a regular basis, indoor air quality is significantly improved and reduces the potential of suffering from any illnesses. The better indoor air quality will also reduce the impact of mould, which releases harmful spores, building up in rooms, like bathrooms and kitchens which generate a lot of moisture.

There is another reason for ensuring the ductwork is cleaned and that dirty, clogged up ductwork will affect the efficiency of the heating, cooling, ventilation or air conditioning system.  With clean ductwork, the system is able to perform at its optimum level. This is particularly important for workplaces where the air quality must be at its highest.

Places like hospitals, care homes and hospitals, and even laundry rooms, generate a higher level of dust and pollutants that travel through the ductwork. Keeping them clean not only improves the air quality but also reduces the risk of fire hazards, breakdowns and subsequent downtime.

What are the legal implications?

Employers are legally obligated to ensure their employees’ working environment is a healthy and safe place, including indoor air quality, under the Health & Safety at Work Act 1974 and the Occupiers Liability Act 1984. Part of complying with their legal duty is to ensure all ductwork within the building is cleaned and maintained on a regular basis.

The TR19® Guide to Good Practice – Internal Cleanliness of Ventilation Systems provides employers with best practice guidance on how to test and maintain high standards. It also incorporates the UK and European standards with regard to air ductwork, particularly kitchen extraction ductwork to minimise the build-up of grease which can cause a fire risk.

To ensure good indoor air quality, optimum performance and compliance with legal requirements, set up a ductwork cleaning schedule. For ductwork that is of low use, every 12 months is recommended but if usage is higher, plan for every 6 or even 3 months.