The light absorption over the entire light path is integrated, which gives an average

concentration over this path. This makes the technique less suitable for measurements

very close to sources (e.g. in a street) and not directly comparable with point

measurements at such sites. However, the technique is suitable for measurement of

urban background concentration, where the small scale spatial variations from small

local sources are not relevant or directly describing the information about the urban

background air pollution. The calibration of the instrument is easy and stable over

long time periods.

Reference methods for ambient air monitoring should fulfil the following criteria:

· be accurate and precise

· fully comply with the Directive requirements

· give data in the correct time scale

· be easily applied and operated

The chemiluminescence method is recommended as reference method for mandatory

concentration measurements. It can easily validate other methods. Equivalent methods

may be used, if they are shown to be in agreement with the reference method.

The reference method must be calibrated correctly, see chapter 3.5 to produce good

quality results.


n121 - n122 - n123 - n124 - n125 - n126 - n127 - n128 - n129 - n130 - n131 - n132 - n133 - n134 - n135 - n136 - n137 - n138 - n139 - n140 - n141 - n142 - n143 - n144 - n145 - n146 - n147 - n148 - n149 - n150



     Flag of Portugal 


 castellano: DISPER CUSTIC DESCAR RADIA    italiano:     


 français:    português:  






deutsch: DIS CUS  DES  RAD

castellano: DIS CUS DES  RAD   english: DIS CUS DES RAD  


 português: DIS CUS DES RAD   italiano:   DIS CUS  DES RAD


français:  DIS CUS DES RAD