 - For cohorts including suction blisters Cohorts 3-5 only: Presence of skin abnormalities that would either interfere with study procedures for example; tattoos, naevi, sun burnsun bed use within 7 days or increase the risk to the subject for example: history of keloids, skin allergy, hypersensitivity or contact dermatitis, including previous reactions to dressings to be used in the study, as determined by the investigator. 