PTM - Physical Test Methods - 2005
- To propose and maintain CORESTA Recommended Methods (CRMs) and related documents for the physical testing of tobacco, tobacco products and their components.
- To organise interlaboratory testing related to Objective 1.
The Physical Test Methods (PTM) Sub-Group is a Sub-Group of the Product Technology Study Group and was established in October 2005 under the name of Monitoring and Maintenance of Physical Test Methods (MMPTM) Sub-Group. It was renamed to its current name in April 2011. The PTM Sub-Group's revised objectives, as listed above, were approved by the Scientific Commission and the Board in June 2018.
Since its creation the PTM Sub-Group has made substantial progress towards these objectives. It has conducted numerous international collaborative studies, published CORESTA Recommended Methods, CORESTA Guides and Technical Reports.
The PTM Sub-Group usually meets twice per year and the meetings are attended by 15 to 20 participants representing cigarette manufacturers, suppliers of materials and instruments for the cigarette industry, analytical laboratories and research institutions.
Development and Maintenance of CRMs
Currently the PTM Sub-Group is developing a method for the measurement of snus pouch sealing strength. A final draft of the method is currently being circulated for comments and a collaborative study to assess the variability of the method will be carried out, so that publication of the new CRM is targeted for early 2019.
In April 2014, CRM 77 on the determination of diffusion capacity was published. This publication finalised a development work of more than four years, which was originally triggered by the need to measure the diffusion capacity of bands on lower ignition propensity cigarette papers. Most of the work was carried out in a separate working group usually meeting in close connection to regular PTM Sub-Group meetings. Within the near future it is planned to revise this method and provide an updated version of the CRM.
The following CRMs are in the responsibility of the PTM Sub-Group.
- CRM 06: Determination of Ventilation - Definitions and Measurement Principles
- CRM 16: Lamina Strip Particle Size Determination
- CRM 17: Stem Content of Lamina Strips
- CRM 40: Determination of Air Permeability of Materials used as Cigarette Papers, Filter Plug Wrap and Filter Joining Paper including Materials having an Oriented Permeable Zone
- CRM 41: Determination of the Draw Resistance of Cigarettes and Filter Rods
- CRM 53: Determination of Paper Wrapper Burn Speed
- CRM 77: Determination of Diffusion Capacity by Measurement of CO2 Transfer Rate Through Material Used as Cigarette Papers and Cigarette Papers having an Oriented Zone of Reduced Diffusion Capacity
Development of CORESTA Guides
As a complement to CRMs, CORESTA Guides cover more practical aspects of the measurement of physical parameters of tobacco products and their components and help the users in applying CRMs. Guides are also developed to give an overview over measurement principles and to document best practices.
The last Guide published by the PTM Sub-Group is Guide No. 14 “A User Guideline for the Determination of the Diffusion Capacity (D*) of Cigarette Papers” which was developed and published in connection with CRM 77.
The PTM Sub-Group has published the following Guides:
- Guide No. 04 – A User Guideline for the Measurement of Pressure Drop of Cigarette and Cigarette Filter Rods
- Guide No. 06 – A User Guideline for the Use of Balances for Cigarettes and Cigarette Related Products
- Guide No. 10 – A User Guideline for the Measurement of Diameter of Cigarettes and Filter Rods
- Guide No. 14 – A User Guide for the Determination of the Diffusion Capacity (D*) of Cigarette Papers
Inter-Laboratory Collaborative Studies
On the one hand inter-laboratory studies are usually carried out during the development of a CRM to determine repeatability and reproducibility of the newly developed method, but on the other hand they are also regularly carried out in the form of a proficiency test to allow laboratories to assess their performance with respect to other laboratories. Particularly for accredited laboratories, participation in such proficiency tests is required.
The PTM Sub-Group generally carries out an annual collaborative study on physical parameters, in which filter rods and cigarettes are measured for weight, diameter, pressure drop and ventilation. These studies are statistically evaluated and the results are made publicly available in form of a Technical Report. In 2018, the PTM Sub-Group carried out its 11th Collaborative Study on Physical Parameters. Usually about 15 to 25 laboratories participate in such a collaborative study.
Furthermore, a smaller number of PTM Sub-Group members maintain calibration laboratories. In order to assess the performance of their calibration laboratories, inter-laboratory studies are carried out regularly as round robin tests. In these studies calibration standards for pressure drop, air permeability and filter ventilation are circulated between the laboratories for measurement. The results are statistically evaluated and also made publicly available as a Technical Report. As the measurement of calibration standards is a high-precision method, which requires sophisticated equipment and a highly controlled laboratory environment, only a very few laboratories participate in these studies. Also, due the time required for the circulation of the calibration standards, the studies are often not carried out on an annual basis.
Reviewed December 2018
Recommended Methods : No. 6 - Determination of Ventilation - Definitions and Measurement Principles09/2016 Recommended Methods : No. 77 - Determination of Diffusion Capacity by Measurement of CO2 Transfer Rate Through Materials Used as Cigarette Papers and Cigarette Papers having an Oriented Zone of Reduced Diffusion Capacity04/2014 Recommended Methods : No. 41 - Determination of the Draw Resistance of Cigarettes and Filter Rods06/2007 Recommended Methods : No. 53 - Determination of Paper Wrapper Burn Speed05/2002 Recommended Methods : No. 40 - Determination of Air Permeability of Materials used as Cigarette Papers, Filter Plug Wrap and Filter Joining Paper including Materials having an Oriented Permeable Zone10/1994 Reports : 11th Collaborative Study (2018) for Physical Parameters of Cigarettes and Filters12/2018 Reports : 4th Round Robin Test for Air Permeability Calibration Standards10/2018 Reports : 5th Round Robin Test for Multi-Capillary Ventilation Calibration Standards (2016/2017)06/2018 Reports : 10th Collaborative Study (2017) for Physical Parameters of Cigarettes and Filters03/2018 Reports : 12th Round Robin Test for Multi-Capillary Pressure Drop Calibration Standards (2016/2017)11/2017 Reports : 3rd Proficiency Test (2017) on Diffusion Capacity of Cigarette Papers05/2017 Reports : 4th Round Robin Test for Multi-Capillary Ventilation Calibration Standards (2015/2016)04/2017 Reports : 11th Round Robin Test for Multi-Capillary Pressure Drop Calibration Standards (2016)04/2017 Reports : 9th Proficiency Test (2016) for Physical Parameters of Cigarettes and Filters04/2017 Reports : 8th Proficiency Test (2015) for Physical Parameters of Cigarettes and Filters02/2017 Reports : 7th Proficiency Test (2014) for Physical Parameters of Cigarettes and Filters02/2017 Reports : 3rd Round Robin Test for Air Permeability Calibration Standards12/2016 Reports : 3rd Round Robin Test for Multi-Capillary Ventilation Calibration Standards (2014/2015)11/2016 Reports : Recommendation of Measurement Area for Air Permeability Determination of Super-Slim Cigarette Papers09/2016 Reports : 10th Round Robin Test for Multi-Capillary Pressure Drop Calibration Standards (2014)08/2016 Reports : 2nd Round Robin Test for Multi-Capillary Ventilation Calibration Standards (2013/2014)08/2016 Reports : 2015 Proficiency Test Report - The Measurement of Diffusion Capacity of Cigarette Papers09/2015 Reports : Collaborative Study to Evaluate a Paperboard Substitute for a Diffusion Capacity Standard08/2015 Reports : 2014 Proficiency Test Report - The Measurement of Diffusion Capacity of Cigarette Papers07/2015 Reports : 2014 Collaborative Study for the Determination of Repeatability and Reproducibility of CRM 7706/2015 Reports : Tobacco Moisture, Water and Oven Volatiles07/2014 Reports : Recommendation of Measurement Area for Air Permeability of Super Slim Cigarette Papers05/2012 Reports : Comparison of Ventilation Standard Calibration Methods05/2012 Reports : Hardness Measurement on Cigarettes and Cigarette Filter Rods03/2011 Reports : Physical Properties of Special Filters11/2010 Reports : MMPTM 2009 Interlaboratory Proficiency Test08/2010 Guides : No. 14 - A User Guide for the Determination of the Diffusion Capacity (D*) of Cigarette Papers10/2013 Guides : No. 10 - A User Guideline for the Measurement of Diameter of Cigarettes and Filter Rods03/2011 Guides : No. 6 - A User Guideline for the Use of Balances for Cigarettes and Cigarette Related Products04/2009 Guides : No. 4 - A User Guideline for the Measurement of Pressure Drop of Cigarettes and Cigarette Filter Rods11/2008