2026 UK guidance: Measuring secondhand vaping aerosol (PM2.5) and VOCs in pubs — ventilation and monitoring best practice

Introduction

The UK’s 2026 guidance on indoor vaping exposures provides practical, venue‑level advice for pubs, clubs and other hospitality settings on measuring secondhand e‑cigarette emissions and managing ventilation. It stresses that e‑cigarette aerosol is not just "harmless water vapour": the aerosol can contain nicotine, ultrafine particles (measured as PM2.5/PM10) and volatile organic compounds (VOCs) that are measurable in indoor air. This article explains the guidance, the science behind the recommendations, and what pub operators and local regulators should do to measure and reduce exposures.

Key concepts: what the guidance is addressing

• What is being measured? Two main pollutant groups: particulate matter (particularly PM2.5) and volatile organic compounds (TVOCs and specific VOCs).
• Why it matters: Peer‑reviewed studies and reviews show indoor vaping can raise indoor PM2.5 and VOCs substantially and that non‑users can register measurable biomarkers (e.g. cotinine, 1,2‑propanediol) after exposure.
• Primary control: Ventilation and adequate air exchange — the guidance prioritises engineered ventilation rates and monitoring over ad‑hoc measures such as intermittent windows‑open policies alone.

Evidence summary

Regulatory and scientific bodies such as the American Industrial Hygiene Association (AIHA) and multiple peer‑reviewed reviews emphasise that e‑cigarette aerosol contains nicotine, ultrafine particles and VOCs that are detectable in indoor air. A notable high‑density vaping event study published in the Journal of Exposure Science & Environmental Epidemiology reported mean PM2.5 concentrations around 197 µg/m3 and median TVOCs approx. 0.13 ppm during sessions, illustrating how quickly indoor concentrations can spike when multiple people vape in the same enclosed space.

Details of the 2026 guidance

The guidance sets out two complementary aims: (1) standardised monitoring protocols so measurements are comparable across venues and time, and (2) practical ventilation rate targets and action thresholds for pubs.

Recommended monitoring protocols

• Continuous PM2.5 monitoring: Use calibrated optical real‑time PM2.5 instruments placed at occupant breathing height in representative areas (e.g. bar, near seating, near doors/windows). Log data at 1‑minute to 5‑minute intervals to capture peak spikes during busy periods.
• VOC sampling: Combine real‑time TVOC sensors with periodic sorbent tube sampling analysed in a lab for specific VOCs and formal quantification. This gives both indicative trends and substance‑specific data.
• Placement and background control: Monitor both indoor and outdoor background simultaneously. Place monitors near likely source zones (where people gather and vape) and in occupied zones to estimate actual user exposure.
• Contextual logging: Record occupancy, observed vaping activity, type of devices and e‑liquids when possible — emission levels vary with device power, PG/VG ratios and puffing behaviour, so contextual notes are important.
• Reporting and thresholds: The guidance recommends predefined action levels (see below) and periodic public reporting to local regulators where required.

Ventilation rate recommendations

The 2026 guidance emphasises engineered ventilation rather than ad‑hoc airing. Key recommendations include:

• Minimum supply of outdoor air: Aim for at least 10 litres per second per person (10 L/s/p) in general pub spaces as a baseline.
• Air changes in busy areas: Target a time‑weighted average of 6 air changes per hour (ACH) for general areas, with at least 10–12 ACH in high‑density sections (e.g. dancefloors, crowded bars or during advertised vaping events).
• Boost ventilation at peaks: When monitoring shows rapid PM2.5 or TVOC increases, increase mechanical ventilation rates or activate rapid extraction to reduce concentrations quickly.
• Design matters: Ventilation strategy and extractor/intake placement influence pollutant removal — mechanical systems generally outperform natural ventilation and extractor fans when properly sited and balanced.

These targets are intended to reduce the duration and magnitude of indoor spikes; they do not imply zero exposure but aim to keep time‑weighted exposures lower and more comparable to background urban indoor air.

Action thresholds and what to do when levels rise

• Reference levels: The World Health Organization 24‑hour guideline for PM2.5 is 15 µg/m3; vaping events can produce short peaks far above that. The guidance recommends operational action if indoor PM2.5 exceeds 25–50 µg/m3 (increase ventilation) and immediate corrective measures if levels approach or exceed 150–200 µg/m3 (investigate sources, reduce occupancy, increase extraction).
• VOC action: Use TVOC real‑time trends to trigger additional ventilation; the guidance suggests laboratory analysis if TVOC peaks exceed typical indoor baselines (e.g. sustained >0.3 ppm) to identify specific compounds requiring mitigation.
• Follow‑up monitoring: After interventions, monitor to confirm reductions and log effectiveness for future planning.

Practical steps for pub operators and local regulators

• Install continuous PM2.5 monitors and maintain a routine VOC sampling plan. Choose instruments suitable for hospitality environments and calibrate them regularly.
• Review HVAC settings to meet the L/s per person and ACH targets; consider higher rates for busy evenings.
• Use placement and behaviour logs to interpret spikes — emission levels vary with device type and e‑liquid. For example, high‑VG shortfills such as 0mg Fantasi 100ml Shortfill (70VG/30PG) or sweet flavour blends like 0mg Dr Vapes Bubblegum Kings 100ml Shortfill (78VG/22PG) tend to produce denser visible aerosol than higher‑PG mixes and will affect local measurements.
• Recognise the wide product variance — from cartridge systems such as 0mg Ezee e‑cigarette cartridges (Tobacco, 1050 puffs) to high‑puff disposables like the 0mg iFresh 10000 puffs 2in1 Disposable Pod Kit — and plan monitoring around likely device mixes.
• Engage local public health and building services early when designing mitigation strategies; extract/intake placement and maintenance are crucial.

Conclusion

The 2026 UK guidance gives pubs and regulators a practical, evidence‑based framework for measuring and managing secondhand vaping aerosol and VOCs. By combining standardised PM2.5 and VOC monitoring with clear ventilation targets and action thresholds, venues can better protect staff and customers from transient but measurable indoor spikes. The guidance underscores a simple point: reliable ventilation and monitoring are more effective than ad‑hoc measures. For operators, investing in the right sensors, reviewing HVAC performance, and recording vaping activity will make compliance straightforward and help maintain healthier indoor air.