1.1 General
This International Standard specifies procedures for the extraction and measurement
of filterable particulate matter from stationary source flue gas samples by:
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— the use of cyclone samplers;
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— the measurement of condensed particulate matter using dilution sampling technique,
which simulates the interaction of stack gas components with the atmosphere as they
mix after the stack exit.
This International Standard provides for the use of two types of sampling train.
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— Basic sampling train, a basic sampling train to measure filterable particles using
sampling cyclones that can distinguish between particle sizes in the range of 2,5 μm
and 10 μm. This method is especially suitable for measurements of particle mass concentrations
above 50 mg/m3 as a half-hourly average at standard conditions (293 K, 1 013 hPa, dry gas) and applies
to primary particulate matter (PM) emissions equal to or less than an aerodynamic diameter of nominally 10 μm (PM10) from stacks or ducts.
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— Dilution sampling train, a dilution sampling train that utilizes a dilution chamber
that mixes flue gas with conditioned dilution air to simulate the interaction of the stack gas components with ambient air. This simulation
process may lead to the condensation of particulate matter that might not otherwise
be produced in the basic sampling train. The dilution sampling train uses in-stack
sampling cyclones to measure filterable particles in the same manner as the basic
sampling train, but in addition, utilizes additional PM2,5 and/or PM10 cyclones in the sampling train to measure particles formed in the dilution chamber.
This method is intended for the measurement of mass concentrations of particles smaller
than 2,5 μm aerodynamic diameter (PM2,5) using weighing techniques. The method can be used to measure mass concentrations
of particles with aerodynamic diameter smaller than 10 μm aerodynamic diameter (PM10) or particles with aerodynamic diameters between 2,5 μm and 10 μm.
In this method, the dilution sampling train can be used in combination with the basic
sampling train, using PM10 and/or PM2,5 depending upon the test objectives. The dilution sampling system is intended for applications where measurement is required of particles similar in
characteristics to materials formed when a flue gas exhaust mixes with ambient air.
Particulate matter filter samples collected using dilution sampling can be further
analysed to provide chemical composition data that are applicable for developing PM2,5 or PM10 emission inventories, visibility impact assessments, health risk assessments, and
source–receptor studies related to PM2,5 and PM10 emissions.
This method is not applicable to the determination of ultrafine particles with an
aerodynamic diameter of less than 0,1 μm. This method has been applied to emission sources with low moisture
and saturated moisture stack gases; however, it is not applicable to effluents where
entrained water droplets are present.
NOTE Optionally, with additional equipment, as well as sampling and analytical procedures
not described in the method, PM chemical speciation and particle size can be determined by applying ambient air sample collection and analysis methods to the diluted stack samples obtained by using this
method. In addition, the concentration of gaseous precursors that can contribute to
the formation of particulate matter, e.g. SO2, NOx, ammonia, SO3, HCl, volatile organic comounds (VOCs), can be determined using suitable analytical equipment to measure the diluted samples.