4 Hour Patch Test

The objective of the study is to assess the likelihood of excessive skin irritation of the test materials when applied cutaneously to approximately 30 healthy subjects, for up to 4 hours. A control material is included in the study as standard.

A preliminary group of 3 subjects is exposed to the test and control materials for 15 min, 30 min and 1h with skin assessments observed immediately, 1h and 24h after patch removal. If satisfactory results are obtained the remaining 27 volunteers enter the main study, where exposure is carried out over 3 days. Test materials are applied for 2h, 3h and 4h with skin sites assessed immediately and 1h, 24h, 48h and 72h after patch removal.

Skin reactions would be assessed by highly trained assessors, throughout the course of the study and a programme of statistical analysis would be conducted at the end to analyse and compare the study results for Erythema, Oedema and Exudation.