Comparison of diffusive and active sampling methods for the determination of nitrogen dioxide in urban air.

The NO/NO,-monitor and the iodide method are compared with a diffusional sampler for the sampling and determination of nitrogen dioxide in urban air. The results for the diffusional sampler were within 20% of the two other methods for weekly averages. The iodide method and the NO/NO,-monitor showed good agreement; the deviation was within 5%.