The fluid handling capacity of some dressings (when tested to EN 13726-1)  is now so high that they create a partial vacuum in the test chamber, distorting the dressing and causing inverse doming. This can stretch the dressing, thereby increasing the surface area of the dressing leading to significant over-estimates of the dressings fluid handling capacity.

The UK have undertaken some inter-laboratory investigations which show that this issue can be resolved through the use of a plate including a small vent hole (0.25mm diameter) which allows pressure to equalise, thus stopping dressing doming.  An anonymised version of this report is available as a PDF.

In addition, the challenge volumes specified in the standard are too low for some dressings, resulting in misleading results. This can be overcoe by using a larger initial fluid challenge.

EN 13726 is presently the subject of a European Standards Working Group (TC/205/1 WG15 PG1) revision, where these solutions are being considered. 

SMTL can offer amendments to the standard test methods which result in more reliable and appropriate values for fluid handling capacity.  Please indicate whether you wish to use the amended methods when commissioning the test programme from SMTL.