Based on 50 participants with sensitive skin. Applying the product to volunteers and a closed chamber for 3 days. 
HRIPT stands for Human Repeat Insult Patch Test. It is a patch test conducted on human volunteers to evaluate the potential for skin irritation or sensitisation caused by a particular substance. The product and patches are applied to the skin and left for 24-48 hours. The HRIPT follows a repeated insult procedure, this is repeated over a period of time of 9 to 21 days.