ASTM recently announced a significant update to ASTM F1929-12 “Standard Test Method for Detecting Seal Leaks in Porous Medical Packaging by Dye Penetration.” The dye leak standard, ASTM F1929, was first written in 1998 and was re-approved in 2004. The update to the standard marks the first significant change in the past few years. Cited by of ISO 11607-1 as a method to test package integrity, F1929 is a dye penetrate integrity test used by package engineers that is designed to detect and locate leaks caused by channels formed between a transparent film and a porous material.
The update results in three different dye application methods. In the past, the only option was by injection (Method A) where the dye solution was exposed to the seal from the inside of the package. With this revision, however, two new test methods have been developed, edge dip (Method B) and the eyedropper (Method C). These two new methods give manufacturers a new opportunity to perform dye leak testing without exposing the product to a significant amount of dye, causing less mess, and using less dye. Below are descriptions of the methods that can be considered when choosing a method for evaluating a sealed package.
Method A – Injection: The method involves injecting dye into the package covering the longest edge with a depth of approximately 0.25 inches of dye. The dye is allowed to contact the sealed edge for a maximum of five seconds and a channel would be detected within this time, if present. The package is then rotated in order to expose the dye to the remaining sides of the package.
Method B – Edge Dip: This method is performed by dipping the package into a dye filled container exposing the entire seal edge to the dye solution so that it briefly contacts the dye along the entire length of the seal, just long enough to wet the edge. The package is then removed and inspected for channels. This method exposes the exterior of the package to the dye in order to detect channels. The edge dip method may be preferred because needles or syringes are not used, and is faster to perform.
Method C – Eye Dropper: This method involves using an eye dropper to apply dye along the edge of the package seal between the transparent and porous materials. Method C requires packages to have excess material along the outside of the seal to contain the dye. As in method B, channels are detected from the exterior to the interior of the package. The channel, if present, will manifest itself in the same way as Methods A & B, that being through capillary action.
DDL actively works with customers to select the best test method for their package and situation as each dye method is subject to change depending on the packaging materials. DDL has conducted package integrity tests, for over 20 years and recommends the use of Method A due to its consistency and applicability to more package designs. Although DDL is able to perform all three test methods, ultimately, it is a customer’s decision as to which method they’d prefer to use.