Contaminated air handling units and ductwork circulate dust, mould, bacteria and allergens throughout your building. TR19 Air 2026 sets the standard for how clean your ventilation system must be — and how that must be measured and documented.
Over time, ventilation ductwork accumulates a range of contaminants. These aren't just an aesthetic issue — they directly affect the health of building occupants, the efficiency of your HVAC system, and your legal compliance obligations.
Poor indoor air quality is linked to increased sick days, reduced cognitive function and higher rates of respiratory illness. The Health and Safety at Work Act requires employers to provide clean, healthy air.
HEALTH & SAFETY LAWDirty AHUs and ductwork restrict airflow, forcing fans to work harder and consuming significantly more energy. Clean systems can reduce HVAC energy consumption by up to 30%.
ENERGY SAVINGSTR19 Air 2026 requires documented cleanliness assessments for ventilation systems. Facilities managers, building owners and employers all have obligations under health and safety law.
TR19 AIR 2026TR19 Air 2026 is the updated BESA standard for the cleanliness of ventilation systems. It replaced the previous TR19 document and introduced more rigorous measurement and documentation requirements for all types of ductwork — not just kitchen extract systems.
The standard sets maximum acceptable dust deposit levels for different duct surfaces, measured in mg/m². These must be recorded before and after cleaning to demonstrate compliance.
Where required, TR19 Air 2026 allows for microbiological sampling to assess bacterial and fungal contamination levels — particularly relevant in healthcare, food production and education settings.
Remote camera inspection of inaccessible duct sections is used to assess conditions and provide before/after evidence. This is a requirement for full TR19 Air compliance documentation.
A Post-Work Verification Report is issued confirming dust deposit levels are within the TR19 Air 2026 standard — your legal compliance record for insurance and regulatory purposes.
Full survey of AHU and ductwork. Dust deposit levels measured and recorded. Camera inspection of inaccessible sections where required.
Full internal clean of air handling unit — coils, fans, drain pans, filter housings and internal surfaces decontaminated and cleared of debris.
Mechanical agitation and extraction of dust and contaminants from supply and extract ductwork. Access panels opened, cleaned, and properly resealed.
Dust deposit levels re-measured and recorded. PWVR certificate issued within 24 hours confirming TR19 Air 2026 compliance.
TR19 Air 2026 recommends frequency based on system type and usage. As a general guide: systems in occupied offices and schools should be assessed every 2-3 years. High-risk environments (healthcare, food production) may require annual cleaning. We'll assess your system and advise.
For AHU cleaning, the system will be offline during the work. We recommend carrying out ductwork cleaning outside of occupied hours to avoid disruption and dust disturbance. Early morning or weekend slots are available.
TR19 Grease specifically covers kitchen extract systems where grease contamination is the primary concern. TR19 Air 2026 covers all other ventilation systems (offices, schools, hospitals, AHUs etc) where dust and microbiological contamination are the focus.
Yes — significantly. Studies consistently show that clean ductwork and AHUs reduce airborne particulates, dust and allergens in occupied spaces. Many building managers report noticeable improvements in air freshness within days of a clean.
We work across all commercial sectors in Yorkshire including offices, schools and colleges, healthcare facilities, hotels and hospitality, retail, industrial units and manufacturing premises.
Full TR19 Air 2026 compliance — clean, healthy air for your building occupants, with documented proof of compliance issued within 24 hours.
Request a Free Quote →