In the field of cosmetic product testing, there are several types of Safety Patch Testing that can be conducted depending on the claims and where you plan to market your products. 

We will provide a brief explanation of 48/96-hour patch tests, along with the Human Repeat Insult Patch Test, more commonly known as HRIPT or RIP for short.

Patch testing methods

These evaluation techniques are designed to gauge the possibility of irritation or allergic reactions triggered by beauty or domestic products. The specific duration chosen, whether 48-hour/96-hour or a 6 week trial, depends on factors such as the requirements of the customer and the nature of the product being tested.

96-hour patch

A 96-hour patch test is conducted with a minimum of 30 subjects to investigate the skin irritation potential of the test product, along with 2 standard controls (one negative and one positive). This study involves four 23-hour patch applications, with reactions being scored 1 hour after the first, second, third, and fourth patch removal.

48-hour patch test

The 48-hour patch test is much the same, however with only two, 23 hour patch applications, this is more commonly used for wash off products such as soaps & shampoo.

Human Repeat Insult Patch Test (HRIPT)

The HRIPT is a globally accepted form of patch test. It involves applying patches, grading skin irritation after their removal, and then reapplying the patches. This process continues for 6 weeks, followed by a rest phase before challenge patches are applied and graded.

These testing methods serve the purpose of assessing the potential irritancy or allergic reactions caused by cosmetic or household products. The specific duration chosen, whether 48hr/96hr or a 6-week trial, depends on factors such as the requirements of the customer and the nature of the product being tested.

These tests can then be used to support the following claims:

  • Dermatologically tested
  • Clinically tested
  • Safe for skin
  • Kind to skin                              
  • Mild for skin

Additional HRIPT Claims Available by request.

  • Hypoallergenic
  • Dermatologist Tested
  • Dermatologist Approved
  • Paediatrician Approved
  • Safe/Suitable for Sensitive Skin
  • Safe/Suitable for Eczema Prone Skin
  • Safe/Suitable for all skin types
  • Safe/Suitable for all skin tones (Fitzpatrick I-VI)


Take the next step

If you would like to know more about the services ADSL provides or speak to our User Trials and Claims team please call +44 (0) 1803 520 048 or book a free video consultation with us using the ‘Get Started’ link below. 



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