|
Title:
|
|
Karakterisering van de regionale concentratievelden van ammoniak :monstername en meetstrategie
|
|
|
|
Author(s):
|
|
|
|
|
|
Published by:
|
Publication date:
|
|
ECN
|
1995
|
|
|
|
ECN report number:
|
Document type:
|
|
ECN-C--95-109
|
ECN publication
|
|
|
|
Number of pages:
|
Full text:
|
|
40
|
Download PDF
|
Abstract:
Five different samplers are tested for their appropriateness to determinemonthly average concentrations of ammonia in the ambient air. The samplers
were diffusion tubes, which varied in their length and coverage, and a
low-flow denuder. The measured results of those samplers were compared with
the measured results of a reference continuous-flow denuder for different
locations and during twelve periods of four weeks. Also, the impacts of
meteorological conditions on the measurements were studied. Based on the
accuracy of and agreement between the data of the samplers and the reference
sampler it appeared that two types of passive samplers are very suitable for
the measurement of monthly ammonia concentrations: a 7 cm diffusion tube,
covered by a stainless steel gaze and a 3.5 cm diffusion tube, covered by a
synthetic membrane. The last sampler will be used in a follow-up study to
characterize regional concentration fields of ammonia. In order to develop a
measurement strategy to characterize regional concentration fields of ammonia
the spatial variability of the ammonia concentration in two areas of 5x5 km
is investigated by means of model simulations and measurements. A minimum of
8 measuring points per area are required to realize an acceptable
determination of the annually average ammonia concentration. 19 figs., 5
tabs., 10 refs., 2 appendices
Back to List