Leak test related questions

  1. Why methylene blue use for leak testing and how much percentage for blister,strips. 2.why we don’t use leak tested tablets for reprocessing(packing) . 3.what is leak test principle. Can any one send answers to above questions.

Why methylene blue use for leak testing and how much percentage for blister,strips.
Methylene blue dye or another colored liquid were use to determine whether or not there is a leak during leak testing of particular pack. If there is a leak in sealed pack , the liquid will seep into the package, thereby giving visual proof. However now day , due to carcinogenicity its banned.
Few drop of methylene blue is well enough for producing light blue solution, which is required for good visualization proof for any leakage pack.
Why we don’t use leak tested tablets for reprocessing (packing)?
We cann’t using the leak tested tablets/capsules for reprocessing/packaging as its intactness might be fail due to vacuum apply during leak testing. Regulatory agency never prefer for reprocess/re-packaging after leak testing.


Principle: vacuum Will create inside leaked pack during vacuum hold time and when we release the vacuum, methylene blue solution enter into leaked pack due to negative pressure inside pack.

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Mr. Dusyant,

Carcinogenicity wth respect to what ? as we are hadling with wearing gloves and there in no chance for intake…

Carcinogenicity:Not listed as a known or possible carcinogen by ACGIH, NIOSH, OSHA, NTP or IARC.
Skin:Absorption into the body may cause cyanosis. May color the skin a bluish color. May cause photosensitization. Wear the protective gloves before use.
Therapeutic use: it has been used to treat cyanide poisoning and to lower levels of METHEMOGLOBIN.

What happens if we will not use dye during leak test and is it specified in guidelines to use dye during test?

Dye is not necessary for dry injection vial. but it is necessary for liquid injection.


is a suitable reference

The name of dye test in USP 1207.2 is Tracer liquid test