In regular round robin tests carried out since 2011 pressure drop calibration standards with a nominal pressure drop range useful for measurements of combustible cigarettes and filter rods were circulated.  However new product categories may have substantially lower pressure drops.  It was thus of interest whether pressure drop standards with a value below 200 mmWG could be manufactured and calibrated and which r&R can be expected in the calibration process.

The Physical Test Methods (PTM) Sub-Group carried out a first round robin test, covering the period between September 2021 and January 2023, to serve as an initial baseline for the precision to be expected when calibrating instruments for low pressure drops.  Recommendations include the verification of the calculation model used to compensate deviations from standard conditions for it applicability to low pressure drops, and the regular circulation of the calibration standards in round robin tests.