The Physical Test Methods (PTM) Sub-Group carries out a regular collaborative study related to air permeability, an important parameter of wrapping papers for tobacco products. The method for measuring air permeability is specified in ISO 2965:2019.  This ISO standard allows the use of the 2×15 mm² measuring head for air permeability measurement on cigarette paper, whenever the available area on the paper sample is too small for the 10×20 mm² measuring head. This may be the case for measurements on paper samples taken from cigarettes or other finished tobacco products.

The first Collaborative Study provided the r&R data for the 2×15 mm² measuring head (allowed by ISO 2965:2019), and the second study served to verify these results. 

Except for one laboratory, this third study showed that all the participating laboratories were able to reliably measure air permeability.  This study allows the participating laboratories to monitor their performance in comparison to other laboratories, to derive actions for improvement of their internal processes and to fulfil accreditation requirements.