Products that are likely to be packaged in permeable materials, such as paper or cardboard, need to be tested in high-humidity conditions.
Thus, a common combination is 37 °C/70% relative humidity (RH) or 40 °C/80% RH. This type of testing is most useful for boxed laundry powders (particularly those destined to be sold in tropical climates), but may be important for the ‘Eve’ soap if it is to be sold in a wrapper or carton rather than a tightly sealed pack.