Application Areas - Environmental Particulate Monitoring

Fine Dust Aerosol Spectrometry

Analysis of Ambient Dust Levels Environmental Particulate

The monitoring and analysis of particulate matter (PM) in the atmosphere is increasingly important given the identified adverse health effects associated with the inhalation of fine particulate matter. This material can accumulate in the lungs and any toxic chemicals present can then be adsorbed into the body.

Allowable and target levels are total mass concentration based (µm/m3) and have been set regionally for PM10 alone or together with PM2.5 levels.

Measurement of the total mass is one aspect of analysis, but a full description of the size distribution for the fine particles allows the better identification of source and measurement of the impact of subsequent actions taken to reduce the pollution at source.

The FIDAS® range of environmental spectometers is a range of robust and well characterised instruments offering analysis of PM1, PM2.5, PM4, PM10 and TSP. The range includes models designed for both indoor and outdoor use (with integrated webserver for remote operation). To allow full analysis of the measured aerosol, a filter holder is included in the sample flowpath to allow for total gravametric and chemical analysis of collected particulate.

Particulate Matter (PM)

The potential for adverse impact on health of fine atmospheric particulate matter (PM) has been known for many years. The science is continually developing but generally speaking particles less than 10 micrometers in diameter (PM10) pose a health concern because they can be inhaled into and accumulate in the respiratory system.

In 1996 the Department of Health’s Committee on the Medical Effects of Air Pollutants (COMEAP) estimated that in Great Britain PM10 pollution was associated with around 8,100 deaths brought forward and 10,500 hospital admissions that were either brought forward or would not otherwise have happened.

Particles less than 2.5 micrometers in diameter (PM2.5) are referred to as "fine" particles and are believed to post the largest health risks. Because of their small size, fine particles can lodge deeply into the lungs.

Sources of fine particles include all types of combustion (motor vehicles, power plants, wood burning, etc.) and some industrial processes.

Particles with diameters between 2.5 and 10 micrometers are referred to as "coarse." Sources of coarse particles include crushing or grinding operations, and dust from paved or unpaved roads.

Legislation and Monitoring in the UK

In Europe, the Air Quality Framework Directive (96/62/EC) defines the policy framework for 12 air pollutants known to have a harmful effect on human health and the environment, which includes PM.

The UK's Air Quality Standards Regulations 2007 came into force on 15 February 2007, replacing the previous Air Quality Limit Values Regulations 2003 that gave effect to the provisions of Air Quality Framework; First; Second; and Third Air Quality Directives; and give effect to the latest Fourth Air Quality Daughter Directive too.  The new Regulations apply to England with the exception of Regulation 29 (relating to reporting requirements) which applies to the entire UK.

A new air quality directive (2008/50/EC) came into force in June 2008 which provides a new regulatory framework for PM2.5 and was to be transposed into national legislation by June 2010. The UK has been granted a delay in the requirement to meet the PM10 limits to June 2011 for a number of identified regional zones identified to currently exceed the limit.

The standard applying to field measurements is EN 12341: 1998 “Air Quality — Field Test Procedure to Demonstrate Reference Equivalence of Sampling Methods for the PM10 fraction of particulate matter” . The measurement principle is based on the collection on a filter of the PM10 fraction of ambient particulate matter and the gravimetric mass determination.

In the UK, DEFRA is responsible for the current Air Quality Objectives and the targets for PM as:

 
Air Quality Objective Conc.
Measured As
To be Achieved by
Particulate Matter PM10
50 µg m-3, not to be exceeded more than 35 times a year
Daily Mean
31 December 2004
40 µg m-3
Annual mean
31 December 2004
Particulate Matter PM2.5
25 µg m-3 (target)
Annual mean
2020
20% cut in urban background exposure
Annual mean
2010 — 2020