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St. Catharines Air Quality Index (AQI) | Air Pollution

Real-time PM2.5, PM10 air pollution level in St. Catharines

Last Updated: 2026-09-30 01:01 (Local Time)

Live AQI

57AQI (US)

Air Quality is

Moderate

PM2.5 : 16 µg/m³

pm10 : 17 µg/m³

Good

050

Moderate

100

Poor

150

Unhealthy

200

Severe

300

Hazardous

301+

17 °C

Last Updated: 2026-09-30 01:01 (Local Time)

Rank693^rd

Currently, St. Catharines ranks 693^rd among the cities with the highest AQI levels in the world.

Map

St. Catharines

Major Air Pollutants
St. Catharines

Particulate Matter(PM₂.₅)

16µg/m³

Particulate Matter(PM₁₀)

17µg/m³

Carbon Monoxide(CO)

281ppb

Sulfur Dioxide(SO₂)

2ppb

Nitrogen Dioxide(NO₂)

11ppb

Ozone(O₃)

19ppb

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AQI Graph

Historical Air Quality Data
St. Catharines

24 Hours

AQI (US)

St. Catharines

AQI (US)

29-09-2026Time30-09-2026

Time	St. Catharines
1:01am	38
1:31am	40
2:01am	40
2:31am	42
3:01am	38
3:31am	38
4:01am	48
4:31am	40
5:01am	42
5:31am	42
6:01am	52
6:31am	52
7:01am	38
7:31am	38
8:01am	38
8:31am	36
9:01am	46
9:31am	50
10:01am	46
10:31am	38
11:01am	45
11:31am	44
12:01pm	56
12:31pm	54
1:01pm	46
1:31pm	44
2:01pm	42
2:31pm	44
3:01pm	42
3:31pm	46
4:01pm	42
4:31pm	42
5:01pm	46
5:31pm	46
6:01pm	40
6:31pm	40
7:01pm	36
7:31pm	34
8:01pm	46
8:31pm	42
9:01pm	38
9:31pm	40
10:01pm	52
10:31pm	54
11:01pm	49
11:31pm	50
12:01am	50
12:31am	54
1:01am	57

Min. AQI (US)7:31pm

Max. AQI (US)1:01am

Want air quality data?

AQI (US) Trends - Annual Air Quality Changes
St. Catharines, Ontario, Canada

AQI (US)

St. Catharines's Locations
Real-time Air Pollution Level

locations

Status

AQI (US)

PM₂.₅(µg/m³)

PM₁₀(µg/m³)

Temp.(°C)

Humi.(%)

St Catharines

Moderate

Canada's Metro Cities
Air Quality Index

Calgary

Edmonton

Montreal

Ottawa

Toronto

Vancouver

Windsor

Winnipeg

Air Quality Calendar 2026
St. Catharines

2026

AQI (US)

Health Advice For People Living In
St. Catharines

0Cigarettes per day

Weekly 0 Cigarettes

Monthly 0 Cigarettes

Breathe easy and get active! The air quality is perfect for enjoying outdoor activities.

Source:

Berkeley Earth

Disclaimer: This cigarette-equivalent estimate is based on the average PM2.5 concentration over the last 24 hours, assuming continuous exposure during that time.

Solutions for Current AQI (US)

Air PurifierTurn On

Car FilterMust

N95 MaskMust

Stay IndoorMust

Prevent Health Problems: Understand Your Risks

St. Catharines

Asthma

Heart Issues

Allergies

Sinus

Cold/Flu

Chronic (COPD)

Disclaimer: The above health risks are precautionary suggestions based on current AQI levels. You may not feel the effects immediately, but prolonged exposure to air pollution can contribute to these health conditions over time. AQI.IN is neither a medical expert nor a provider of medical advice. Please consult a doctor if you experience any of the above similar symptoms.

Most Polluted Cities 2026
Canada

Analyze the real-time most air polluted cities in the country.

Most Polluted Cities Live Ranking 2026

World's Most PollutedCity Rankings (2025)

World's Most PollutedCountry Rankings(2025)

RankCityAQI Status

Standard Value

London, Ontario

Moderate

2xabove Standard

Belleville, Ontario

Moderate

1xabove Standard

Winnipeg, Manitoba

Moderate

1xabove Standard

St Catharines, Ontario

Moderate

1xabove Standard

Waterloo, Ontario

Moderate

1xabove Standard

Guelph, Ontario

Moderate

1xabove Standard

Toronto, Ontario

Moderate

1xabove Standard

Ottawa, Ontario

Moderate

1xequal Standard

Brampton, Ontario

Moderate

1xequal Standard

10.

Gatineau, Quebec

Moderate

1xequal Standard

Last Updated: 30 Sept 2026, 05:04 AM

AQI City Rankings

Air Quality Solutions For St. Catharines
Explore the solutions of air quality monitoring & clean air.

Here are some applications that you can go through to find out the solutions.

Air Quality Monitor

Monitor the air quality

Air Quality Sensors

Sensors to measure the air quality

Fresh Air Machine

Clean the air you breathe

Car Cabin Filter

Purify the air in your car

N95 Mask

Shield yourself from pollution

Prana Air offers the solutions of air quality monitoring and clean air machine for St. Catharines

Air Quality Solution For Offices

A complete solution for air quality monitoring, data analysis, and fresh air solutions in workplaces prioritizing employee's health and productivity.

Air Quality Solutions For Smart City

Prana Air smart city project provides air quality monitors, drones, outdoor air purifiers, and data dashboards solution to improve air quality.

Air Quality Solutions for Schools | Institutes

Prana Air provides the air quality solutions for schools by air monitoring & fresh air machine that help the students to breather clean air.

Air Quality Solutions For Hotels

Prana Air air quality solutions are suited for hotel businesses. The occupancy of hotels is the main reasons for bad air quality.

Air Quality Solutions for Restaurants

Prana Air has the air quality solutions for restaurant, cafes, and gives you the power to know what your customers and staff breathe.

Air Quality Solutions for RMC Plants

Prana Air provides air quality monitoring solutions for RMC plants. Improve compliance, protect workers and community, and reduce emissions.

Air Quality Solutions for Fitness Center

Prana Air provides the air quality solutions of pollution monitoring and fresh air for fitness center - gym.

Air Quality Solutions for Parking Lot

A complete solution for air monitoring, data analysis, and fresh air solutions for enclosed car parking areas and car lots.

Air Quality Solutions for Retail Stores

Prana Air provides air quality solutions of pollution monitoring and fresh air for retail stores and shopping outlets.

Prana Air provides air quality solutions of pollution monitoring and fresh air for retail stores and shopping outlets

Prana Air provides the air quality solutions for airport. Gathering of many passengers is the main reasons of bad air quality in airport.

Air Quality Solutions For Construction Sites

Prana Air offers air quality monitoring solutions for construction sites with data cloud storage, web-dashboard, mobile apps, TV display.

Air Quality Solutions For Hospitals

Prana Air provides air quality monitoring and fresh air solutions for hospitals to ensure clean and healthy indoor air.

Air Quality Solutions For Washroom | Bathroom

Improve washroom and bathroom air quality with Prana Air air quality monitoring devices and fresh air machine. Breathe easy and stay healthy.

Air Quality Solutions for Banks

Prana Air provides air quality solutions of pollution monitoring and fresh air for banks and financial institutions.

Air Quality Solutions for Cinema

Air quality solutions for cinema halls or theatres will help the customers to get the good experience, comfort and breathe clean air.

Air Quality Solutions For Real Estates

Prana Air provides the air quality solutions of pollution monitoring and fresh air for real estates - residential and commercial.

St. Catharines's AQI Data Analytics Solutions
Air quality data monitoring platforms

Mobile App

Smart TV App

Web Dashboard

API

Widgets

Air Quality FAQs
at St. Catharines

Frequently Asked Questions About Air Quality

1. What is the current AQI (US) level in St. Catharines?

The current real-time AQI (US) level in St. Catharines is 57 (Moderate). This was last updated 2026-09-30 01:01 (Local Time).

2. When was the best AQI (US) level in St. Catharines in the last 24 hours?

The best AQI (US) level was 34 (Good) at 7:31 PM, Sep 29, 2026 (Local Time) during the last 24 hours.

3. When was the worst AQI (US) level in St. Catharines in the last 24 hours?

The worst AQI (US) level was 57 (Moderate) at 1:01 AM (Local Time) during the last 24 hours.

4. What is the current trend of AQI (US) levels in St. Catharines during last 24 hours?

The AQI (US) levels in St. Catharines have been fluctuating throughout the last 24 hours. The levels have increased by highest 57 at 1:01 AM (Local Time), lowest 34 at 7:31 PM, Sep 29, 2026 (Local Time).

5. What actions are recommended as per the current AQI (US) level in St. Catharines?

Current AQI (US) levels are acceptable; however, some pollutants may be a concern for a small number of sensitive individuals.