Do you need ventilation when using incense?
Executive summary
Ventilation reduces concentrations of particulate matter (PM) and volatile organic compounds (VOCs) from incense and is repeatedly recommended by scientists and public-health commentators as the practical way to lower exposure when burning incense indoors [1] [2]. Studies report indoor PM and VOC peaks from incense that can exceed ambient standards and cigarette-home levels, and measurements in poorly ventilated temples and rooms show much higher PM2.5/PM10 than in ventilated settings, so ventilation is a key mitigation step [3] [4] [5].
1. Why experts say ventilation matters: combustion products and where they go
Incense combustion emits particulate matter (PM), ultrafine particles and a mix of VOCs — including benzene and other hazardous compounds — that linger in indoor air; poor ventilation traps those pollutants and raises concentrations well above outdoor or background levels [6] [7] [3]. Environmental health reviews explicitly note that fine and ultrafine PM from incense can penetrate deep into the lungs and drive systemic inflammation — a pathway linked to cardiovascular and respiratory harm — and they single out poor ventilation as a driver of elevated exposures [3] [1].
2. What the measurements show: numbers and real-world examples
Field studies document wide variation but consistent patterns: PM1 and PM2.5 averages measured inside a naturally ventilated church were substantially lower than values in more poorly ventilated temples, and PM10 near altars was far higher in sealed conditions than when ventilation was present [4] [5]. Some studies report PM concentrations from incense that exceed ambient air quality guideline ranges and, in homes, can rival concentrations found in households with frequent cigarette use [3] [5].
3. What ventilation actually does — and how well it works
Ventilation dilutes and removes emissions: opening windows, using exhaust fans, or increasing air exchange lowers contaminant concentrations in the short term, and controlled experiments show that establishing strong aeration can remove a high percentage of VOCs within hours after burning ceases [2] [6]. Air-cleaning technology also reduces exposure—one study reported a personal NTP air purifier cut exposure by about 64% in a liturgical setting—yet ventilation remains the straightforward first-line control [4].
4. Limits and trade-offs: ventilation is necessary but not always sufficient
Researchers and reviews emphasize that ventilation reduces but does not eliminate exposure; pollutant peaks still occur during and immediately after burning, and prolonged or frequent incense use, especially in crowded or poorly ventilated indoor spaces, sustains higher cumulative exposure [2] [7] [8]. In cold climates or energy-conserving situations, occupants may keep windows closed, creating a trade-off between thermal comfort and air quality that complicates simple ventilation advice [8].
5. Practical harm-reduction steps grounded in the literature
Sources offer clear, implementable measures: prefer source control (reduce frequency, choose lower-emission products) and, when burning incense, use effective ventilation such as exhaust fans or open windows, limit burn duration, increase distance from the burning point, and consider supplemental air purification to further lower exposure [2] [1] [5]. Manufacturers and policy interventions are also cited as preferable long-term strategies to reduce emissions at source [2].
6. Who is most at risk — and why that matters for policy
Authors identify children, elderly people, and those with preexisting cardiovascular or respiratory conditions as particularly vulnerable to the effects of incense smoke; cohort and observational studies link incense exposure with cardiovascular and pregnancy-related outcomes in some populations, underscoring why ventilation guidance appears prominently in public-health recommendations [3] [7].
7. Competing perspectives and unanswered questions
While many studies and reviews urge ventilation and report pollutant peaks, available sources also note gaps: more long-term epidemiology with robust controls is needed to quantify chronic risk and to define safe exposure thresholds for varied cultural practices [9]. Some field work finds lower fragrance-related risks in specific contexts, but all the cited work nonetheless recommends ventilation where incense is used [5] [9].
8. Bottom line for a practical user
If you burn incense indoors, ventilate: open windows or run exhaust fans during and after burning, limit duration and frequency, increase distance from the burning point and consider air cleaning—these steps are repeatedly recommended in the literature as the most effective, immediate way to lower exposure to PM and VOCs from incense [1] [2] [4].