This document specifies the procedure to sample continuously and to analyse the concentration of airborne pollen grains and fungal spores in ambient air using the volumetric Hirst type sampler [1] [2] [3] (see Annex A) or an even equivalent method assuring comparable data. This document describes both the sampling and the analysis procedures for the purpose of networks related to allergy. For the other tasks mentioned in the introduction@ other specifications may be required.