What Is TR19?
TR19 is the industry standard guide published by the Building Engineering Services Association (BESA) for the internal cleanliness of ventilation systems. It provides benchmark standards for ductwork hygiene and defines when remediation is required.
For facilities managers and building operators, TR19 compliance is not optional — it is a fundamental part of maintaining healthy, safe indoor environments and demonstrating duty of care.
Why Ventilation Hygiene Matters
Contaminated ductwork can harbour dust, biological growth, and other pollutants that are continuously distributed throughout occupied spaces. The consequences include:
- Increased occupant complaints about air quality and odours
- Elevated risk of respiratory illness and sick building syndrome
- Reduced HVAC efficiency and higher energy costs
- Non-compliance with health and safety obligations
What Does a TR19 Assessment Involve?
A thorough TR19 assessment includes:
- Visual inspection — internal examination of ductwork using access panels and remote cameras
- Surface sampling — swab or vacuum tests measured against TR19 cleanliness benchmarks
- Photographic evidence — before and after documentation for compliance records
- Compliance report — clear, actionable findings with remediation recommendations where needed
How Often Should Testing Be Done?
BESA recommends assessments at least annually, though higher-risk environments (healthcare, food preparation, laboratories) may require more frequent checks. Green Air Monitoring supports FM teams with scheduled PPM contracts that ensure consistent compliance without the administrative burden.