Reasons Why the Test May Fail

Should the test fail a re-test should be performed. If the test fails a second time, a diagnosis of both the method of cleaning and method of testing is required.

The compliance team at Isopharm is also available to discuss the test and test method.

Possible fail reasons for a Protein Residue Test are:

Diagnosing the Method of Cleaning

• Detergent residue may present a false positive. This is usually caused when the detergent used has been changed but the level of dosing has not.
• Instruments handled excessively during testing may cause a false positive. Gloves should always be worn when performing a protein residue test.
• In some cases it may be that the machine under test is not working correctly and an engineer may be required to diagnose further.

Diagnosing the Method of Test

• Check that the test product used is within the expiry date provided.
• Check what was used to moisten the swab. Tap water may present a false positive result. Always use Clean-Trace moisturiser as this has been validated for use within the test.
• Gloves should always be worn when performing a protein residue test as this reduces the amount of contaminant from handling the test products.