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Measuring Sub-23 Nanometer Real Driving Particle Number Emissions Using the Portable DownToTen Sampling System

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Particulate air pollution in transport micro-environments.

Zaheer Ahmad Nasir¹, Ian Colbeck

¹Department of Biological Science, University of Essex, Wivenhoe Park, Colchester, CO4 3SQ, United Kingdom.

Journal of Environmental Monitoring : JEM

|June 11, 2009

Summary

Particulate matter levels were higher in non-air-conditioned trains and similar in cars. Air-conditioned train PM10, PM2.5, and PM1 concentrations varied significantly between peak and off-peak journeys.

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Composition and Distribution Analysis of Bioaerosols Under Different Environmental Conditions

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Published on: January 7, 2019

Area of Science:

Environmental Science
Air Quality Monitoring
Public Health

Background:

Particulate matter (PM) exposure in transport environments is a growing public health concern.
Understanding PM dynamics in trains and cars is crucial for assessing commuter exposure.

Purpose of the Study:

To investigate and compare particulate matter (PM10, PM2.5, PM1) concentrations inside air-conditioned and non-air-conditioned train coaches and public cars.
To analyze the influence of journey times (peak vs. off-peak) and time of day (morning vs. evening) on PM levels.

Main Methods:

Field study conducted between 2004-2006 measuring PM concentrations in various transport modes.
Data collected during peak and off-peak train journeys and morning/evening car journeys.
Statistical analysis to determine significant differences and correlations in PM levels.

Main Results:

Air-conditioned coaches showed significantly higher PM10 (44 µg/m³), PM2.5 (14 µg/m³), and PM1 (12 µg/m³) during peak times, with levels halving during off-peak.
Non-air-conditioned coaches exhibited high PM10 (up to 95 µg/m³) in both peak and off-peak periods.
Car journeys showed consistent PM10 (21 µg/m³), PM2.5 (9 µg/m³), and PM1 (6 µg/m³) with no significant difference between morning and evening, but a spike in October.
Significant correlations found between morning and evening PM levels in cars.

Conclusions:

Transport environments, particularly non-air-conditioned trains, can be significant sources of particulate matter exposure.
Air-conditioned trains offer better PM control, but journey timing still impacts levels.
Car PM levels are relatively stable but can be influenced by external pollution events.