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Air Quality Index (AQI) in Yuen Long Kau Hui, Hong Kong 🇭🇰

Air quality in Yuen Long Kau Hui is currently 79 on the US AQI scale, rated Moderate.

Patchy rain nearby
28°C
Patchy rain nearby
AQI INDEX
79
US EPA Standard

PM 2.5 Level
24.0
µg/m³

Air Quality
Moderate
The current Air Quality Index (AQI) in Yuen Long Kau Hui is recorded at 79 as of 10:59 AM local time this Friday, August 21, 2026. This real-time AQI score is estimated from the current PM2.5 concentration. According to the US EPA health standard, air quality in Yuen Long Kau Hui currently falls into the Moderate category. The PM2.5 pollution levels are currently measured at 24.0 µg/m³. While this AQI level is acceptable for most people, those who are unusually sensitive to air pollution should consider reducing prolonged or heavy exertion outdoors. If you are sensitive to air pollution, check the local weather before heading out. For the AQI across entire Hong Kong, you can also view the Air Quality Index for Hong Kong covering other major urban centers and local monitoring stations.

Health Recommendations for Yuen Long Kau Hui Residents

⚠️

Air quality is acceptable. However, for some pollutants there may be a moderate health concern for a very small number of people. Sensitive groups should consider reducing prolonged outdoor exertion.

Yuen Long Kau Hui Air Pollution: Detailed Pollutant Breakdown

🚬
Breathing Yuen Long Kau Hui's air today is roughly like smoking 1.1 cigarettes.
Based on the Berkeley Earth estimate that ~22 µg/m³ of PM2.5 over a day is about one cigarette. Today's PM2.5 in Yuen Long Kau Hui is 24.0 µg/m³.
PM 2.5
24.0
µg/m³
PM 10
27.9
µg/m³
Nitrogen Dioxide (NO2)
60.0
µg/m³
Ozone (O3)
29.0
µg/m³
Carbon Monoxide (CO)
185.0
µg/m³
Sulfur Dioxide (SO2)
37.5
µg/m³

Current Weather in Yuen Long Kau Hui

🌡️ 28°C (Feels like 32°)
🌬️ 15 km/h S
💧 75% Humidity
🧭 1002 hPa
👁️ 10.0 km Visibility
☀️ UV Index: 0.3
🌅 Sunrise: 06:03 AM
🌇 Sunset: 06:50 PM
🌡️ Dew Point: 23°C

Yuen Long Kau Hui's Main Air Pollutant Today

The main concern in Yuen Long Kau Hui right now is NO2 at 60.0 µg/m³, about 2.4x the WHO 24-hour guideline.

Air Quality Health Advice for Yuen Long Kau Hui

General publicAir quality is acceptable for most people. Outdoor activity is fine.
Sensitive groupsUnusually sensitive people should consider easing prolonged or heavy exertion outdoors.

Air Quality in Other Cities in Hong Kong

Browse Air Quality in Hong Kong by cities in alphabetical order:

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Air Quality in Hong Kong ›

Frequently Asked Questions about Air Quality in Yuen Long Kau Hui

What is the air quality (AQI) in Yuen Long Kau Hui right now?

The current air quality index in Yuen Long Kau Hui is 79 — categorised as Moderate.

Is the air in Yuen Long Kau Hui safe to breathe today?

Today's air quality in Yuen Long Kau Hui is rated Moderate on the US EPA scale.

What is the PM2.5 level in Yuen Long Kau Hui right now?

The fine-particle (PM2.5) concentration in Yuen Long Kau Hui is currently 24.0 µg/m³. PM2.5 is the most health-relevant pollutant — the WHO 24-hour guideline is 15 µg/m³.

What is the PM10 level in Yuen Long Kau Hui right now?

The coarse-particle (PM10) concentration in Yuen Long Kau Hui is currently 27.9 µg/m³.

What is the main pollutant in Yuen Long Kau Hui right now?

The dominant pollutant in Yuen Long Kau Hui right now is NO2 at 60.0 µg/m³.

Is it safe to exercise outdoors in Yuen Long Kau Hui today?

With air quality currently rated Moderate, outdoor exercise in Yuen Long Kau Hui is generally considered safe for most people.

How to Read the Air Quality Index for Yuen Long Kau Hui

Good (0-50)

Air is fresh and healthy. Safe for all outdoor activities.

Moderate (51-100)

Acceptable air quality, though sensitive groups should monitor comfort.

Unhealthy (Sensitive) (101-150)

Vulnerable groups (children, elderly) should limit outdoor exertion.

Unhealthy (151-200)

Everyone begins to experience health effects. Stay indoors where possible.

Very Unhealthy (201-300)

Significant health impact for entire population. Emergency conditions.

Hazardous (301+)

Serious health alert: everyone may experience serious life-threatening effects.

Good (0-12)

Fine particles are at minimal, safe levels. Air is optimal.

Moderate (12-35)

Acceptable air, but haze may be present in urban areas.

Sensitive (35-55)

Individuals with heart or lung disease should limit activity.

Unhealthy (55-150)

Particulate levels high enough to cause respiratory irritation.

Very Unhealthy (150-250)

Heavy haze. High risk to cardiovascular health for the public.

Hazardous (250+)

Lethal particulate concentrations. Critical neurological and lung risk.

Good (0-54)

Low levels of dust and coarse particles. Environment is safe.

Moderate (55-154)

Coarse particles may trigger coughing in sensitive groups.

Sensitive (155-254)

Visible dust pollution. Sensitive groups should avoid heavy labor.

Unhealthy (255-354)

Widespread respiratory impacts likely for the population.

Very Unhealthy (355-424)

Dangerous dust and debris levels. Significant warnings issued.

Hazardous (425+)

Extremely high concentrations. Stay inside with filtration.

Good (0-54)

Surface ozone levels are within a safe, natural range.

Moderate (55-70)

Acceptable air, but sensitive individuals may feel chest tightness.

Sensitive (71-85)

Rising ozone can trigger airway inflammation in active children.

Unhealthy (86-105)

Avoid heavy outdoor work during the hottest part of the day.

Very Unhealthy (106-200)

Serious lung function reduction likely across the public.

Hazardous (201+)

Emergency ozone levels. Risk of permanent lung tissue damage.

Good (0-53)

Nitrogen levels are optimal. Safe for everyone.

Moderate (54-100)

Typical background levels for high-density urban areas.

Sensitive (101-360)

Increased risk of respiratory infections for vulnerable groups.

Unhealthy (361-649)

Significant airway inflammation likely near traffic zones.

Very Unhealthy (650-1249)

Acute respiratory distress potential. High-risk groups stay indoors.

Hazardous (1250+)

Toxic concentrations. Immediate health precautions required.

Good (0-4.4)

Carbon Monoxide levels are clean and non-toxic.

Moderate (4.5-9.4)

Acceptable; may affect those with specific heart conditions.

Sensitive (9.5-12.4)

Reduced oxygen delivery to the heart may occur.

Unhealthy (12.5-15.4)

Headaches and fatigue may occur in urban canyons.

Very Unhealthy (15.5-30.4)

Significant cardiovascular distress. Mental confusion possible.

Hazardous (30.5+)

Lethal potential. Immediate risk of neurological collapse.

Good (0-35)

Optimal air quality with no sulfur detection.

Moderate (36-75)

Acceptable air; minor odors possible near industry.

Sensitive (76-185)

Bronchoconstriction possible for active asthmatics.

Unhealthy (186-304)

Respiratory distress likely for the wider population.

Very Unhealthy (305-604)

Significant wheezing and shortness of breath likely.

Hazardous (605+)

Extreme respiratory danger. Significant life risk.

Health & Scientific Resources

→ How to read US EPA Air Quality Index before going outside → Understanding Air Quality Index levels and what they mean → When haze forms and what it does to air quality

How is this AQI calculated?

The primary Air Quality Index (AQI) shown above is calculated using the US EPA Linear Interpolation formula based on PM2.5 concentration (Fine Particulate Matter).

Formula: Ip = [(Ihi - Ilow) / (Chi - Clow)] * (Cp - Clow) + Ilow
Current Conditions Explained

Is the AQI in Yuen Long Kau Hui safe today?

Today's AQI is 79, which is categorized as Moderate. This means the air quality is moderate for the general population.