DIN CEN/TS 16115-1:2011-07

This Technical Specification describes the measurement of moulds in ambient air in order to identify, quantify and characterize bioaerosol pollution in ambient air resulting from emissions from different sources. The method described specifies the sampling of moulds as part of the suspended particulate matter (SPM, here particles with aerodynamic diameter up to ca. 30 µm) using a filter sampling system with gelatine/polycarbonate filter combination followed by the culture-based analyses on DG18 agar. The sampling duration can be varied between 10 min to 24 h. The health effect of bioaerosols is not limited to any particle fraction, therefore, this document describes the sampling of moulds as part of the suspended particulate matter as a convention method. During filtration, a defined air quantity is sucked through a filter; airborne moulds are collected on gelatine filters resulting in a high total sampling efficiency. Polycarbonate filters are used below the gelatine filters to enhance stability. Biological sampling heads, modified with regard to ambient air measurements of particles, are developed for sampling of bioaerosols. The reason for the modification of the standardised sampling head for suspended particulate matter in ambient air was the reduction of the face velocity in order to decrease the sampling stress for moulds. Additionally, the modifications enable the use of disposable or sterilizable filter holders ensuring aseptic conditions during the handling of filter and sampling head and avoiding carry-over effects and contaminations. With the analytical methods described here, mesophilic and thermotolerant moulds are quantified by cultivation of the viable and culturable propagules on selective DG18 agar. The quantitative determination of the mould concentration is performed by counting the visually recognisable colonies following cultivation. The density of the colonies grown on the culture medium results from the number of dilution steps after suspension of the cells from the filter. Therefore, in principal several dilution steps need to be plated out.

13.040.20