Health Education Centre
Understand India's AQI, air pollutants, health precautions and how DecideKaro.com calculates route exposure estimates.
Important: General Information Only
All content in the Health Education Centre is general public information sourced from WHO, CPCB and Indian government guidance. It is not medical advice, diagnosis or treatment. It does not replace consultation with a qualified healthcare professional. Never stop prescribed medication or alter your treatment plan based on information in this section. If you have a health condition, consult your doctor about precautions appropriate for your specific situation.
Understanding India's AQI
DecideKaro.com uses the official CPCB (Central Pollution Control Board) AQI framework for India. This is a sub-index calculated from eight pollutants: PM2.5, PM10, NO₂, SO₂, CO, O₃, NH₃ and Pb. The highest sub-index value determines the overall AQI. Do not compare CPCB AQI directly with US EPA AQI — they use different scales and calculation methods.
Air quality is satisfactory. Air pollution poses little or no risk.
Air quality is acceptable. Minor discomfort to sensitive individuals.
Members of sensitive groups may experience health effects.
Everyone may begin to experience health effects. Sensitive groups at greater risk.
Health warnings for emergency conditions. Entire population likely to be affected.
Health alert — everyone may experience serious health effects.
Source: Central Pollution Control Board (CPCB), Ministry of Environment, Forest and Climate Change, Government of India. Health guidance text is derived from official CPCB AQI category descriptions.
Key Air Pollutants
| Pollutant | CPCB Standard |
|---|---|
PM2.5Fine Particulate Matter (≤2.5 µm) | 60 µg/m³ (24h avg) · 40 µg/m³ (annual avg) |
PM10Coarse Particulate Matter (≤10 µm) | 100 µg/m³ (24h avg) · 60 µg/m³ (annual avg) |
NO₂Nitrogen Dioxide | 80 µg/m³ (24h avg) · 40 µg/m³ (annual avg) |
O₃Ground-Level Ozone | 100 µg/m³ (8h avg) |
SO₂Sulphur Dioxide | 80 µg/m³ (24h avg) · 50 µg/m³ (annual avg) |
COCarbon Monoxide | 4 mg/m³ (8h avg) |
Why PM2.5 is more dangerous than PM10
PM2.5 particles are about 30× smaller than a human hair. They bypass the nose and throat's natural filters and penetrate deep into the alveoli (air sacs) of the lungs. From there, they can enter the bloodstream and reach the heart and other organs. PM10 particles are larger and are mostly filtered by the upper respiratory tract, causing irritation but less systemic damage.
Why pollution varies street to street
CPCB monitoring stations are placed in fixed locations and may be several kilometres from your actual route. Local sources (a diesel bus stop, an idling truck, construction work) can raise PM2.5 several times above what the nearest station reports. Wind direction, building geometry, and tree cover also affect local concentrations. DecideKaro.com's route exposure estimates use station data as a proxy — they are not direct roadside measurements.
Sources: CPCB National Ambient Air Quality Standards (NAAQS), WHO Global Air Quality Guidelines 2021, Ministry of Environment Forest and Climate Change.
Health Condition Guides
General environmental precautions for people with specific health sensitivities. These are public health information resources — not personal medical advice.
- 1
PM2.5 and NO₂ are the most relevant pollutants for people with asthma. They can trigger bronchospasm at concentrations below the CPCB Moderate threshold.
- 2
Avoid outdoor exercise during AQI Poor (201–300) or above. Morning peak hours (07:00–10:00 IST) often have elevated PM2.5 in Hyderabad.
- 3
Keep reliever inhaler accessible at all times when air quality is Moderate or above.
- 4
Consider wearing a well-fitted N95/FFP2 respirator (not a surgical mask) during heavy outdoor exposure when AQI is Poor or above.
- 5
Monitor AQI before planning outdoor activity. DecideKaro.com shows current CPCB station readings — check the Air Quality Map before leaving.
- 6
Indoor air quality matters too — avoid incense, strong cleaning products and cooking smoke, which can trigger attacks independently of outdoor AQI.
This guidance is based on general CPCB/WHO public health information. Consult your pulmonologist or respiratory physician for a personalised asthma action plan.
How Route Exposure Estimates Work
DecideKaro.com's exposure estimates are modelled estimates — not measured personal doses. They are designed to help you compare routes in a transparent, explainable way. They are not clinical risk scores and do not predict whether you will experience symptoms.
Route Segmentation
The route returned by the routing provider is divided into segments based on available traffic data. Each segment has an estimated travel time.
Pollutant Concentration Assignment
For each segment, DecideKaro.com looks for the nearest available CPCB monitoring station within a configurable radius. The station's current PM2.5 and PM10 readings are used as a proxy for that segment's ambient concentration.
Exposure Integral Estimation
Estimated exposure for each segment = pollutant concentration × time spent in segment. Segment estimates are summed to produce a route-level exposure integral.
Route Cost Scoring
Route cost = travel-time cost + weighted environmental-exposure cost + optional detour penalty. The weighting between time and exposure is configurable based on the selected Route Preference.
Confidence Assessment
Confidence is reported based on station coverage: how many CPCB stations are within range of each route segment, the freshness of their readings, and whether any segments are unmonitored.
Conceptual Formula
// Route scoring
Route cost = travel_time_cost + (weight × exposure_cost) + detour_penalty
// Exposure integral per route
Exposure = Σ (concentration_i × time_in_segment_i)
// where i = each route segment with available station data
Known Limitations
Station readings are from fixed locations — they may not represent air quality at specific road segments.
DecideKaro.com uses ambient outdoor concentrations — in-vehicle concentrations depend on vehicle type, windows, ventilation and filter quality.
Exposure estimates are not personal dose measurements — individual breathing rate, activity level and health status are not modelled.
The scoring system does not mix different pollutant concentrations or AQI sub-indices without scientific justification.
When station coverage is insufficient, the exposure comparison is marked as unavailable or low confidence.
No exposure estimate implies medical safety or guarantees symptom avoidance.
DecideKaro.com is committed to transparency. When data is insufficient to compare exposure reliably, the app shows the traffic route but marks the exposure comparison as unavailable or low confidence. We will never manufacture a numerical pollution score to fill the interface.
Frequently Asked Questions
Sources used in this section: World Health Organization (WHO) Global Air Quality Guidelines 2021 · Central Pollution Control Board (CPCB) National Ambient Air Quality Standards · Ministry of Environment, Forest and Climate Change, Government of India · Telangana State Pollution Control Board (TSPCB). All health guidance is general public information. DecideKaro.com is not affiliated with any of these organisations.