CEN/TC 264/WG 11 - Ambient air quality - Diffusive samplers for the determination of gases and vapours - Requirements and test methods

This document specifies a method for the sampling and analysis of NH3 in ambient air using diffusive sampling.
It can be used for NH3 measurements at ambient levels, but the concentration range and exposure time are sampler dependent, and the end user is therefore advised to match the sampler type to the measurement requirement and to follow the operating instructions provided by the manufacturer.

This European Standard specifies a method for the sampling and analysis of NO2 in ambient air using diffusive sampling followed by extraction and analysis by colorimetry or ion chromatography (IC). It can be used for the NO2 measurement in a concentration range of approximately 3 µg/m³ to 130 µg/m3. A sample is typically collected for a period of 1 to 4 weeks [13], with exposure periods depending on the design of the samplers and the concentration levels of NO2.
Several sorbents can be used for trapping NO2 in ambient air using a diffusive sampler. This standard specifies the application of triethanolamine as the reagent.
Nitrous acid and peroxyacetyl nitrate are the major chemical interferences of sorption by triethanolamine. However, in ambient air monitoring over long sampling times, both contaminants are generally present at low concentrations relative to NO2. Moreover, these species can also interfere with the measurement of NO2 when applying the EU reference method for NO2 monitoring based on chemiluminescence (see [2]).
This standard describes the application of a tube-type sampler with either a cylindrical or a slightly conical tube. Its typical uptake rate is about 1 cm3/min. Only for this sampler type sufficient evidence of validation has been found in a literature survey [12].
The relative expanded uncertainty of NO2 measurements performed using these tube-type diffusive samplers can potentially be lower than 25 % for individual measurements. When aggregating results to form annual average values, the relative expanded uncertainty can be further reduced to levels below 15 % due to the reduction of random effects on uncertainty [6].

This document gives guidelines for the selection, use and maintenance of diffusive samplers used to analyse gaseous pollutants in indoor air including measurement strategy and planning.
This document gives guidelines for the selection, use and maintenance of diffusive samplers used to measure indoor air quality and personal exposure. This document is applicable to indoor air quality assessment because crucial differences to ambient air measurement have to be taken into account concerning environmental parameters, measurement strategy, as well as the nature, number, source and abundance of indoor air pollutants.
In contrast to typical ambient air measurements the appearance of unexpected compounds in indoor air environments is quite common. Procedures to calculate specific uptake rates of these compounds are needed more often as there is only a limited number of uptake rates validated by experiments (see EN 13528-2 and EN 13528-3) to assess the respective concentration values. In addition to the general calculation procedure of the individual uptake rate as given in EN 13528-2 and EN 13528 3 detailed procedures to calculate diffusion coefficients and the uptake rate are given in annex C of this document.

This part of the European Standard gives guidance on the selection, use and maintenance of diffusive samplers used to measure ambient air quality.

This part of the European Standard specifies general performance requirements for diffusive samplers used for the determination of the concentration of gases and vapours in ambient air. Such requirements apply to all diffusive samplers, irrespective of the physical nature of the rate controlling process and irrespective of the nature of the sorption process and the analytical determination. This standard applies to all stages of the measuring procedure, including deployment, transportation and storage of the sample where appropriate.

This part of the European Standard specifies specific performance requirements and test methods under prescribed laboratory and field conditions for diffusive samplers used for the determination of the concentration of gases or vapours in ambient air. Such requirements apply to all diffusive samplers, irrespective of the physical nature of the rate-controlling process and irrespective of the nature of the sorption process and the analytical determination.

This document specifies a method for the sampling of NO2 in ambient air using diffusive sampling followed by extraction and analysis by colourimetry or ion chromatography (IC). It can be used for the NO2 measurement in a concentration range of approximately 3 µg/m3 to 130 µg/m3 [12]. A sample is typically collected for a period of 1 to 4 weeks [14], with exposure periods depending on the design of the samplers and the concentration levels of NO2.
Several sorbents can be used for trapping NO2 in ambient air using a diffusive sampler [15]. This document specifies the application of triethanolamine as the reagent.
This document describes the application of a tube-type sampler (with either a cylindrical or a slightly conical tube), a badge-type sampler and a radial-type sampler.
The relative expanded uncertainty of NO2 measurements performed using these tube-type diffusive samplers can potentially be lower than 25 % for individual measurements. When aggregating results to form annual average values, the relative expanded uncertainty can be further reduced to levels below 15 % due to the reduction of random effects on uncertainty [9].
NOTE   NO2 passive samplers are also employed to measure NOx with the addition of an oxidant to convert ambient NO into NO2. A second NO2 sampler is also deployed without the oxidant and the concentration of NO is determined from the difference of the two samplers [16].