Haze
Singapore experiences haze from time to time, usually caused by forest fires in the region. It can be made worse by dry seasons, changes in wind direction, and when rainfall is low.
Last updated on 21 October 2026
The Pollutant Standards Index (PSI) measures the air quality and indicates the severity of haze. A PSI reading of 101 and above is deemed unhealthy. The 1-hour PM2.5 concentration indicates the current air quality during episodes of haze.
The health impact of haze is dependent on one’s health status (e.g., whether one has pre-existing chronic heart or lung disease), the air quality as measured by the PSI level and 1-hour PM2.5 reading, the duration of exposure and the intensity of outdoor activity.
For healthy individuals, short-term exposure (i.e., over a few days) to haze will generally not cause any major health issues, other than irritation of the eyes, nose, and throat. Unless the 1-hour PM2.5 reading is in Band 4 (Very High) or PSI forecast is hazardous, it is generally safe for healthy individuals to carry on with outdoor activities in most cases, at reduced intensity and/ or duration. However, you should drink plenty of water to stay hydrated. N95 masks (or equivalent) are not needed for commuting from home to school or work. N95 masks (or equivalent) are also not needed in an indoor environment.
Individuals with existing chronic heart and lung conditions should ensure that medications are on hand and readily available.
MOH Advisory for the General Public
While this health advisory provides general precautionary advice, each individual’s reaction to pollutants may vary. The amount of physical activity or exertion that can be performed outdoors during haze periods also differs according to an individual’s health status or capacity. Persons who are not feeling well, especially the elderly and children, and those with chronic heart or lung conditions, should seek medical advice.
For immediate outdoor activities, use the 1-hour PM2.5 reading and personal guide^:
Band 1 (Normal) (0 – 55 µg/m³) | Band 2 (Elevated) (56 – 150 µg/m³) | Band 3 (High) (151 – 250 µg/m³) | Band 4 (Very High) (≥251 µg/m³) |
|---|---|---|---|
Continue with normal activities | Healthy persons – Reduce strenuous outdoor activity for the next hour Vulnerable persons – Avoid strenuous outdoor activity for the next hour | Healthy persons – Avoid strenuous outdoor activity for the next hour Vulnerable persons – Avoid all outdoor activity for the next hour; may wear a mask to reduce exposure | Healthy persons – Minimise all outdoor activity for the next hour; may wear a mask to reduce exposure Vulnerable persons – Avoid all outdoor activity for the next hour; may wear a mask to reduce exposure |
^This guide is not intended to be prescriptive. For the general population, symptoms that may arise from short-term exposure such as throat or eye irritations are expected to resolve after withdrawing from the exposure.
For next day outdoor activities, use the PSI forecast and Health Advisory:
PSI Forecast | 0 – 50 Good | 51 – 100 Moderate | 101 – 200 Unhealthy | 201 – 300 Very Unhealthy | >300 Hazardous |
|---|---|---|---|---|---|
HEALTHY PERSONS | Normal Activities | Normal Activities | Reduce prolonged or strenuous outdoor physical exertion | Avoid prolonged or strenuous outdoor physical exertion | Minimise outdoor activity |
ELDERLY, | Normal Activities | Normal Activities | Minimise prolonged or strenuous outdoor physical exertion | Minimise outdoor activity | Avoid outdoor activity |
PERSONS | Normal Activities | Normal Activities | Avoid prolonged or strenuous outdoor physical exertion | Avoid outdoor activity | Avoid outdoor activity |
Note: Prolonged - continuous exposure for several hours; Strenuous - involving a lot of energy or effort; Reduce - do less; Minimise - do as little as possible; Avoid - do not do
Use of Masks
Reducing outdoor activities and physical exertion can help limit the ill effects from haze exposure. Individuals may refer to the latest 1-hour PM2.5 reading to plan for immediate outdoor activities, including deciding on mask-wearing if they need to be outdoors for several hours when PM2.5 levels are high or very high.
When the 1-hour PM2.5 reading is in Band 4 (Very High), healthy individuals should try to minimise all outdoor activity. However, persons who need to be outdoors for immediate activities may reduce exposure by wearing an N95 mask (or equivalent) with a good fit.
When the 1-hour PM2.5 reading is in Band 3 (High), vulnerable persons such as the elderly, pregnant women and individuals with chronic heart or lung disease should avoid outdoor activity. If they need to be outdoors for immediate activities, they may wear an N95 mask (or equivalent) to reduce exposure. However, the elderly, pregnant women and those with severe lung or heart problems who have difficulty breathing at rest or on exertion should consult their doctor before using an N95 mask (or equivalent).
Women in the 2nd and 3rd trimesters of pregnancy may already have reduced lung volumes or breathing issues, and should not use an N95 mask (or equivalent) for long duration.
Any person who feels discomfort when using an N95 mask (or equivalent) should take a break from using the mask.
N95 masks (or equivalent) must be fitted properly to the face of the wearer for it to effectively protect the user. The mask must be appropriately sized, and cover the nose and mouth comfortably without leaks. This way, most of the air that the wearer breathes in has to go through the filter and not through the gaps between the mask and the wearer’s face.
N95 masks (or equivalent) can be reused during haze, but should not be shared. N95 masks (or equivalent) can be reused so long as they are not soiled/dirty, damp, damaged or out of shape.
N95 masks (or equivalent) can generally be found at major pharmacies and supermarkets such as Guardian, Unity/ FairPrice, Cold Storage/ Giant, Sheng Siong and Watsons as well as their online platforms.
Other masks equivalent to N95 are KN95, FFP2 and KF94. These masks are effective in reducing exposure to haze particles. The differing names reflect their respective national standards.
N95 and equivalent masks:
Certification/ Class (Standard) | N95 (US NIOSH-42CFR84) | KN95 (Chinese GB2626-2006, GB2626-2019) | FFP2 (European, EN 149:2001+A1:2009) | KF94 (Korean, MFDS notice No 2015-61) |
|---|---|---|---|---|
Filter performance* – (must be ≥X% efficient) | ≥95% | ≥95% | ≥94% | ≥94% |
Certification Country | US | China | Europe | South Korea |
*Filter performance: The filter is evaluated to measure the reduction in concentrations of specific aerosols in air that passes through the filter.
N95 and equivalent masks are effective against haze and filtering out PM2.5 particles. Surgical masks can also provide a barrier against larger irritant particles and can reduce discomfort and risk of infections during this time. However, for the general public, if the PM2.5 reading is above 250µg/m³ and you have to be outdoors for several hours, we would advise that you put on a N95 and equivalent mask.
The key precaution for children during haze is to adhere to the haze health advisory and personal guide when planning outdoor activities. Although there are currently no international certification standards for masks meant for use in children, the AIR+ KN95 Mask can be used (only where necessary) by children without heart and lung conditions to protect against the effect of haze, provided it maintains a well-fitted seal at all times.
Haze Subsidy Scheme
The Haze Subsidy Scheme (HSS) helps Singaporeans with their haze-related medical needs at participating Public Health Preparedness Clinics (PHPCs) and all polyclinics.
Find Public Health Preparedness Clinics (PHPCs) which may provide the Haze Subsidy Scheme (HSS) on GPGoWhere (opens in new tab). Participating PHPCs can also be identified by the PHPC decal and/ or the HSS poster displayed at the clinic.
For more information on HSS, please refer to our Frequently Asked Questions (opens in new tab).
PHPC Decal
