CMS/User Guide - Filterteknik

Appendix GTo clarify matters still further, ISO standards written around the new test dustwill utilize a new identifier, ‘(c)’. Hence µm sizes according to the new ISO11171 will be expresses as ‘µm(c)’ and Beta ratios according to ISO 16889will be expressed as ‘Bx(c)’, e.g.‘B5(c)’.However, it must be stressed that the only real effect users will experiencewill be the improved accuracy in particle counts - there will be no changein the performance of filters, nor in the ISO cleanliness levels that they willachieve.The following charts shows the correlation between the old ACFTD and thenew ISO MTD.The CMS is calibrated with ISO Medium Test Dust (to ISO 11171). Thecorrelation between particle sizes and the ACFTD (old standard) to the ISOMTD (new standard) is as follows :ACFTD