Stress is a measure of continued irritation (irritation over time). It is commonly described as the sensation of the brain overruling one’s natural desire to get antisocial, and has measurable physical results such as increased cortisol levels and reduced immune function.
Unit of irritation : 1 RED = 1 Red-light Expedition Deferral –
The irritation of the moment when one is in a hurry and – just at the safe stopping point – the light goes red, so one knows one should stop.
Unit of Irritation over Time : 1 RED-hour = 1 Western Industrialised Student (WIS, pronounced “Whizz”) interacting with a neutral teacher for one hour on a sunny afternoon.
A level of average daily stress associated with lapses of self-control, such as puns or comfort eating, is 9.8 WIS (1 g-WIS)
Erasmid 