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Guidance library
Practical guidance on indoor air quality, ventilation hygiene, and building compliance — drawn from 2,500+ commercial assessments.
Free guides from Green Air Monitoring
Practical checklists for commissioning and reviewing ventilation hygiene work.
How to Read a TR19 Ventilation Hygiene Report
Check methods, results, outcome labels and common red flags.
Read the guideChoosing an Independent Ventilation Hygiene Assessor
Compare providers and ask the right questions before approving cleaning.
Read the guideKitchen Extract Compliance: TR19 Grease Guide
Understand cleaning frequencies, WFTT limits and the records insurers usually request.
Read the guideVentilation Hygiene: Your Duties Explained
A plain-English guide to duties, responsibility and the evidence facilities teams should keep.
Read the guideOn Air articles
All Articles
In-depth guides for facilities managers, building owners, and compliance professionals.
Retrofit ventilation risks under the Warm Homes Plan
The Warm Homes Plan increases retrofit activity and thermal upgrades. Our team outlines the ventilation and indoor air quality risks that follow, practical controls, and how to manage performance and compliance over time.
London's Building Boom Has a Dust Problem
Ongoing high-density redevelopment across London and the South East is increasing dust at sensitive boundaries. This piece explains why boundary dust monitoring matters, how to approach it in practice and what regulators expect.
The 14-Month Countdown: Your LEV Statutory Test Explained
Regulation 9 of COSHH requires a Thorough Examination and Test (TExT) of local exhaust ventilation at least every 14 months. This note explains what that means in practice, the enforcement context and pragmatic steps for reliable compliance.
The Office Is Making Us Ill - What a Reactive Air Quality Investigation Actually Finds
Staff health complaints often prompt a reactive investigation. We explain the stepwise measurement process, common findings from office enquiries and the practical business implications of the results.
The ductwork you cannot see is your legal fire and air quality risk
Hidden ductwork carries both fire and indoor air quality risks. Building owners and facilities teams must treat ventilation hygiene as a compliance and insurance issue, not merely housekeeping.
Awaab's Law Phase 2 Is Coming: Is Your Mould Evidence Good Enough
Phase 2 of Awaab's Law takes effect on 30 November 2026 and requires faster, evidenced action on damp and mould for social landlords. Practical guidance on why spore-trap surveys matter and how to assemble robust evidence.
Sick Building Syndrome: Causes, Investigation, and Solutions
Sick building syndrome causes real health impacts. Learn how to investigate and resolve SBS complaints with a structured approach.
VOC and Formaldehyde Testing in the Workplace
VOCs and formaldehyde in offices cause health complaints. Learn what drives exposure and how testing identifies the source.
TR19 Air Explained: What Building Operators Need to Know
What TR19 Air covers, whether it is a legal requirement, how ductwork cleanliness is measured and what to do with the results.
Mould Risk in Commercial Buildings: Prevention, Assessment, and Remediation
Mould in commercial buildings creates health risks and liability. Learn how to identify, assess, and manage mould effectively.
A Facilities Manager's Guide to IAQ Assurance Contracts
One-off testing gives you a snapshot. Ongoing IAQ assurance gives you confidence, compliance evidence, and fewer surprises.
Why Indoor Air Quality Matters for Commercial Buildings
Poor indoor air quality affects occupant health, productivity, and compliance. Learn why IAQ testing is essential for commercial buildings.
CO₂ Monitoring: The Simplest Indicator of Office Ventilation Performance
CO₂ levels are the most reliable indicator of whether your office ventilation is working. Learn the benchmarks and what to do when levels are high.
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