Workplace IAQ
Office Indoor Air Quality
Independent measurement, benchmarking and remediation guidance for office indoor air quality — the single most cost-effective lever for productivity, absence and Sick Building Syndrome complaints.
The case for measurement
Workplace indoor air quality is the largest controllable influence on cognitive performance
The Harvard COGfx studies, the LBNL ventilation programme and the UK government's CIBSE TM40 working group all converge on the same finding: doubling outdoor air supply to a typical UK office produces measurable improvements in cognitive function, reduces self-reported headache and fatigue, and lowers short-term absence. Office indoor air quality is not a wellness concern — it is the largest controllable influence on workplace productivity.
And yet the average UK office, when continuously monitored, spends 30–50% of occupied hours above 1,000 ppm CO₂ and routinely shows PM2.5 within a few µg/m³ of outdoor traffic concentrations. Workplace indoor air quality drifts upward as buildings are densified, finishes are refreshed and HVAC plant ages — usually without anyone noticing until occupants begin to complain.
An office IAQ assessment quantifies that drift. We measure what the building is actually delivering to the breathing zone, compare it against BS EN 16798-1 and the WELL Building Standard, and identify the engineering changes — usually inexpensive — that bring the workplace back inside its design envelope.
Methodology
A typical office IAQ assessment
- 1
Stage 01
Scoping & symptom log review
Telephone briefing with FM and HR. Review of complaint log, recent refurbishment history, HVAC commissioning records and occupancy density.
- 2
Stage 02
Walk-through inspection
Audit of AHUs, filter condition, supply and extract terminals, recirculation dampers, occupancy density, finishes and known emission sources (printers, kitchens, stored cleaning chemicals).
- 3
Stage 03
Continuous monitoring
Research-grade sensors deployed for 5–10 working days measuring CO₂, PM2.5, PM10, TVOC, temperature and relative humidity at occupant breathing height. Sorbent tubes for formaldehyde and speciated VOCs where indicated.
- 4
Stage 04
Report & remediation plan
Written report benchmarked against BS EN 16798-1, CIBSE TM40 and WHO IAQ Guidelines, with ranked, costed remediation options and a verification re-test scope.
Benchmarks
Office IAQ targets at a glance
| Parameter | BS EN 16798-1 Cat II | WHO / WELL guidance |
|---|---|---|
| CO₂ (above outdoor) | ≤ 800 ppm | ≤ 800 ppm |
| PM2.5 | — | ≤ 10 µg/m³ (24-h) |
| PM10 | — | ≤ 20 µg/m³ (24-h) |
| Formaldehyde | — | ≤ 100 µg/m³ |
| TVOC | — | ≤ 500 µg/m³ |
| Temperature (winter) | 21–23 °C | 21–23 °C |
| Relative humidity | 30–60% | 30–60% |
When to assess
Triggers for an office indoor air quality assessment
Most clients commission an office IAQ assessment after one of four triggers: a cluster of headache, fatigue or respiratory complaints; a major refurbishment or churn; a densification programme or return-to-office surge; or a written grievance, union query or HSE notification. In every case the answer is the same — measure first, then act.
The cost of an assessment is small relative to the cost of unscheduled absence, grievance handling or, in the worst case, lease-break and relocation. The cost of not measuring is that remediation money is spent on the wrong thing: deep-clean budgets, HEPA air purifiers and aromatherapy diffusers that don't address the underlying ventilation or source-control issue.
Where measurements show that the workplace is compliant and the complaints have another cause — workload, lighting, acoustics — we say so. Independence is what makes an office IAQ report useful.
FAQ
Office indoor air quality — common questions
Concerned about your workplace air?
Request an independent office IAQ assessment — typically scheduled within 10 working days. Call 01322 555566.
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