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Air Quality Index (AQI) in Ōmihachiman, Japan 🇯🇵

Air quality in Ōmihachiman is currently 65 on the US AQI scale, rated Moderate.

Partly Cloudy
33°C
Partly Cloudy
AQI INDEX
65
US EPA Standard

PM 2.5 Level
16.4
µg/m³

US EPA Index
2
Moderate
The current Air Quality Index (AQI) in Ōmihachiman is recorded at 65 as of around noon local time this Tuesday, July 21, 2026. This real-time AQI score is based on the highest-risk pollutant measured by local monitoring stations. According to the US EPA health standard, air quality in Ōmihachiman currently falls into the Moderate category. The PM2.5 pollution levels are currently measured at 16.4 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 Japan, you can also view the Air Quality Index for Japan covering other major urban centers and local monitoring stations.

Health Recommendations for Ōmihachiman 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.

Ōmihachiman Air Pollution: Detailed Pollutant Breakdown

🌿
Good news — Ōmihachiman's air today is cleaner than a single cigarette (about 0.7).
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 Ōmihachiman is 16.4 µg/m³.
PM 2.5
16.4
µg/m³
PM 10
18.4
µg/m³
Nitrogen Dioxide (NO2)
0.9
µg/m³
Ozone (O3)
130.0
µg/m³
Carbon Monoxide (CO)
162.0
µg/m³
Sulfur Dioxide (SO2)
2.6
µg/m³

Current Weather in Ōmihachiman

🌡️ 33°C (Feels like 38°)
🌬️ 4 km/h NNW
💧 59% Humidity
🧭 1009 hPa
👁️ 10.0 km Visibility
☀️ UV Index: 10.4
🌅 Sunrise: 04:56 AM
🌇 Sunset: 07:07 PM
🌡️ Dew Point: 24°C

Ōmihachiman's Main Air Pollutant Today

The main concern in Ōmihachiman right now is Ozone at 130.0 µg/m³, about 1.3x the WHO 24-hour guideline.

Air Quality Health Advice for Ōmihachiman

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 Japan

Browse Air Quality in Japan by cities in alphabetical order:

A C F G H I K M N O S T U W Y

Air Quality in Japan ›

Frequently Asked Questions about Air Quality in Ōmihachiman

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

The current air quality index in Ōmihachiman is 65 — categorised as Moderate.

Is the air in Ōmihachiman safe to breathe today?

Today's air quality in Ōmihachiman is rated Moderate on the US EPA scale.

What is the PM2.5 level in Ōmihachiman right now?

The fine-particle (PM2.5) concentration in Ōmihachiman is currently 16.4 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 Ōmihachiman right now?

The coarse-particle (PM10) concentration in Ōmihachiman is currently 18.4 µg/m³.

What is the main pollutant in Ōmihachiman right now?

The dominant pollutant in Ōmihachiman right now is Carbon Monoxide (CO) at 162.0 µg/m³.

Is it safe to exercise outdoors in Ōmihachiman today?

With air quality currently rated Moderate, outdoor exercise in Ōmihachiman is generally considered safe for most people.

How to Read the Air Quality Index for Ōmihachiman

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

Note: While several pollutants (O3, NO2, SO2) are monitored, PM2.5 is used as the primary "driver" for the main index value as it typically represents the highest health risk.

Frequently Asked Questions

What is the main cause of air pollution in Ōmihachiman?

Pollution in Ōmihachiman is primarily driven by 3.6 km/h NNW winds, local traffic emissions, and industrial activity, which influence the current PM2.5 concentration of 16.4 µg/m³.

Is the AQI in Ōmihachiman safe today?

Today's AQI is 65, which is categorized as Moderate. This means the air quality is moderate for the general population.