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Air Quality Index (AQI) in Cát Bà, Vietnam 🇻🇳

Air quality in Cát Bà is currently 30 on the US AQI scale, rated Good.

Light rain shower
26°C
Light rain shower
AQI INDEX
30
US EPA Standard

PM 2.5 Level
5.4
µg/m³

Air Quality
Good
The current Air Quality Index (AQI) in Cát Bà is recorded at 30 as of 6:39 PM local time this Saturday, August 1, 2026. This real-time AQI score is estimated from the current PM2.5 concentration. According to the US EPA health standard, air quality in Cát Bà currently falls into the Good category. With a fine particulate matter (PM2.5) concentration of 5.4 µg/m³, the air pollution levels are considered minimal. This AQI rating indicates that the air is fresh and healthy for the general public, including children and those with respiratory sensitivities. A good day to be outside, so see today's sunrise and sunset and the local weather. For the AQI across entire Vietnam, you can also view the Air Quality Index for Vietnam covering other major urban centers and local monitoring stations.

Health Recommendations for Cát Bà Residents

Air quality is considered satisfactory, and air pollution poses little or no risk. It is a great day for outdoor activities in Cát Bà.

Cát Bà Air Pollution: Detailed Pollutant Breakdown

🌿
Good news — Cát Bà's air today is cleaner than a single cigarette (about 0.2).
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 Cát Bà is 5.4 µg/m³.
PM 2.5
5.4
µg/m³
PM 10
6.9
µg/m³
Nitrogen Dioxide (NO2)
4.6
µg/m³
Ozone (O3)
65.0
µg/m³
Carbon Monoxide (CO)
106.0
µg/m³
Sulfur Dioxide (SO2)
1.7
µg/m³

Current Weather in Cát Bà

🌡️ 26°C (Feels like 30°)
🌬️ 4 km/h NNE
💧 85% Humidity
🧭 1006 hPa
👁️ 10.0 km Visibility
☀️ UV Index: 0.0
🌅 Sunrise: 05:26 AM
🌇 Sunset: 06:30 PM
🌡️ Dew Point: 24°C

Cát Bà's Main Air Pollutant Today

The main concern in Cát Bà right now is Ozone at 65.0 µg/m³, about 0.7x the WHO 24-hour guideline.

Air Quality Health Advice for Cát Bà

General publicAir quality is good. It is a great day to be active outside.
Sensitive groupsAir quality is good. Sensitive groups can enjoy normal outdoor activity.

Air Quality in Other Cities in Vietnam

Browse Air Quality in Vietnam by cities in alphabetical order:

B C D E G H K L M N O P Q R S T V X Y

Air Quality in Vietnam ›

Frequently Asked Questions about Air Quality in Cát Bà

What is the air quality (AQI) in Cát Bà right now?

The current air quality index in Cát Bà is 30 — categorised as Good.

Is the air in Cát Bà safe to breathe today?

Today's air quality in Cát Bà is rated Good on the US EPA scale.

What is the PM2.5 level in Cát Bà right now?

The fine-particle (PM2.5) concentration in Cát Bà is currently 5.4 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 Cát Bà right now?

The coarse-particle (PM10) concentration in Cát Bà is currently 6.9 µg/m³.

What is the main pollutant in Cát Bà right now?

The dominant pollutant in Cát Bà right now is Ozone at 65.0 µg/m³.

Is it safe to exercise outdoors in Cát Bà today?

With air quality currently rated Good, outdoor exercise in Cát Bà is generally considered safe for most people.

How to Read the Air Quality Index for Cát Bà

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 Cát Bà safe today?

Today's AQI is 30, which is categorized as Good. This means the air quality is good for the general population.