What does Indoor Relevant Time Value mean?

All Indoor Climate Labelled products have a so-called Indoor Relevant Time Value given in days. This time value is determined based on the the amount of time that passes until the emission subsides to an acceptable level (based on the standard test method given in ISO 16000-28). The time value is based on a sensory evaluation performed by a panel of at least 15 people. Ceiling products are further classified by the release of particles. By having an Indoor Relevant Time Value it is possible to compare labelled products to each other.