The pattern of office-related headaches
Office-related headaches share a recognisable pattern. Onset late morning or after lunch, worse in enclosed meeting rooms, worse on full-occupancy days, improving within 60–90 minutes of leaving the building, absent on remote-working days. Where multiple staff report the same pattern in the same zone, the cause is almost always environmental — and almost always solvable.
What causes office headaches
The dominant causes are elevated CO₂ (signalling under-ventilation, and itself a mild cerebrovasodilator at sustained levels above 1500 ppm), elevated VOCs (post-refurbishment loading, cleaning products, printers), formaldehyde release from new MDF furniture, and very dry winter air below 30% RH. Less common but worth ruling out: combustion gases from car-park infiltration, mould-related complaints in zones with damp.
Our investigation method
We combine a brief, standardised symptom questionnaire (MM 040 or similar) with two weeks of continuous CO₂, TVOC, temperature and humidity monitoring across the affected zone and a control zone. Where the data implicates VOCs or formaldehyde, we follow up with sorbent-tube laboratory sampling. The combination almost always identifies the cause within 14 days.
Resolving the issue
Where ventilation is the cause, increasing fresh air supply and rebalancing the system typically resolves complaints within a week of the change. VOC and formaldehyde issues respond to source removal and bake-out ventilation. The closing step is always re-measurement, paired with a follow-up symptom survey to confirm the issue has stayed resolved.
Frequently asked questions
Can high CO₂ in offices cause headaches?
Sustained CO₂ above 1500 ppm is associated with headaches, drowsiness and impaired decision-making in controlled studies. CO₂ at office concentrations is also a reliable proxy for elevated VOCs and other co-pollutants from people and activities.
How quickly should headaches resolve after the air is fixed?
If ventilation was the cause, complaints typically fall within one to two weeks of the change. Where VOCs or formaldehyde are involved, the resolution depends on source removal and may take longer.
What should staff do if they think the office is making them ill?
Encourage them to log the pattern (where, when, what improves it). Commission an investigation as soon as a pattern is established — speculation without measurement rarely closes the issue.