Influence of sample temperature and environmental humidity on measurements of benzene in ambient air by transportable GC-PID

Romero Trigueros, Cristina; Doval Miñarro, Marta; González Duperón, Esther; González Ferradás, Enrique

Publication:
Influence of sample temperature and environmental humidity on measurements of benzene in ambient air by transportable GC-PID

dc.contributor.author	Romero Trigueros, Cristina
dc.contributor.author	Doval Miñarro, Marta
dc.contributor.author	González Duperón, Esther
dc.contributor.author	González Ferradás, Enrique
dc.contributor.department	Ingeniería Química
dc.date.accessioned	2025-01-15T11:41:21Z
dc.date.available	2025-01-15T11:41:21Z
dc.date.issued	2017-10-27
dc.description	© Author(s) 2017. This manuscript version is made available under the CC-BY 4.0 license http://creativecommons.org/licenses/by/4.0/ This document is the Published version of a Published Work that appeared in final form in Atmospheric Measurement Techniques. To access the final edited and published work see https://doi.org/10.5194/amt-10-4013-2017, 2017	es
dc.description.abstract	Calibration of in situ analysers of air pollutants is usually done with dry standards. In this paper, the influence of sample temperature and environmental humidity on benzene measurements by gas chromatography coupled with a photoionisation detector (GC-PID) is studied. Two reference gas mixtures (40 and 5 µg m−3 nominal concentration benzene in air) were subjected to two temperature cycles (20/5/20 °C and 20/35/20 °C) and measured with two identical GC-PIDs. The change in sample temperature did not produce any significant change in readings. Regarding ambient humidity, the chromatographs were calibrated for benzene with dry gases and subjected to measure reference standards with humidity (20 and 80 % at 20 °C). When measuring a concentration of 0.5 µg m−3 benzene in air, the levels of humidity tested did not produce any significant interference in measurements taken with any of the analysers. However, when measuring a concentration of 40 µg m−3, biases in measurements of 18 and 21 % for each respective analyser were obtained when the relative humidity of the sample was 80 % at 20 °C. Further tests were carried out to study the nature of this interference. Results show that humidity interference depends on both the amount fractions of water vapour and benzene. If benzene concentrations in an area are close to its annual limit value (5 µg m−3), biases of 2.2 % can be expected when the absolute humidity is 8.6 g cm−3 – corresponding to a relative humidity of 50 % at 20 °C. This can be accounted for in the uncertainty budget of measurements with no need for corrections. If benzene concentrations are above the annual limit value, biases become higher. Thus, in these cases, actions should be taken to reduce the humidity interference, as an underestimation of benzene concentrations may cause a mismanagement of air quality in these situations.	es
dc.format	application/pdf	es
dc.format.extent	10	es
dc.identifier.citation	Atmospheric Measurement Techniques, 2017, Vol. 10, Issue 10, pp. 4013-4022
dc.identifier.doi	https://doi.org/10.5194/amt-10-4013-2017
dc.identifier.issn	Print: 1867-1381
dc.identifier.issn	Electronic: 1867-8548
dc.identifier.uri	http://hdl.handle.net/10201/148475
dc.language	eng	es
dc.publisher	Copernicus Publications	es
dc.relation	We would like to acknowledge the Consejeríade Agua, Agricultura y Medio Ambiente of the ComunidadAutónoma de la Región de Murcia for its financial support and forthe facilities to carry out this work.	es
dc.relation.publisherversion	https://amt.copernicus.org/articles/10/4013/2017/	es
dc.rights	info:eu-repo/semantics/openAccess	es
dc.rights	Atribución 4.0 Internacional	*
dc.rights.uri	http://creativecommons.org/licenses/by/4.0/	*
dc.title	Influence of sample temperature and environmental humidity on measurements of benzene in ambient air by transportable GC-PID	es
dc.type	info:eu-repo/semantics/article	es
dspace.entity.type	Publication	es