For the next phase of testing for Aperture's Disposable undergarments, they had to be heat resistant so they wouldn't catch fire. Parker was chosen for this next test. He was simply instructed to sit down on a heatable panel and tell GLaDOS if he felt any heat. He didn't, at all. This passed the next phase of the testing. As Parker walked back towards the lounge, the aperture ring on the back of his diaper turned red. He asked if that was related to the temperature, but GLaDOS told him it means the diaper is close to causing a rash, because Parker Messed it. Parker was then dragged to a DURS station for a fresh one. Apparently, the diapers are also capable of causing nasty rashes.