Mistakes from the Past Lead to Overregulation in the Future – Do Indoor Air Quality Regulations Promote or Hinder Wood Use in the Building Sector? ——2019世界木材日研讨会
国际木文化学会 | 471 view(s) | 2020/03/19
Different emission dynamics canbe observed following all stages from cradle to grave. Building products suchas CLT or OSB are usually tested under controlled conditions within the firstfour weeks (28 days) after production, and most often do not reach a steadystate in this time span. During the construction phase of wooden buildings, aheterogeneous mixture of building products (also including non-wooden products)and uncontrolled conditions usually lead to unstable and unrepresentativeindoor air conditions. At the time of move-in, stabilization might begin, butadditional emissions from sources such as furniture get introduced, once againgiving an unrepresentative picture of IAQ. Thereafter, IAQ depends mainly onthe air exchange rate, in addition it is also influenced by human activities.Measurements under real-life conditions in a variety of different settingsindicate that a reliable assessment of IAQ should not be made prior to threemonths after move-in, ideally half a year later. In many cases wooden buildingsin use show good or even excellent IAQ, with no toxicological peculiarities atthat time. On the other hand, building industry most commonly can´t wait thatlong, if IAQ measurements are required, e.g. with respect to buildingcertification. In this respect, wood processing industry is constantly forcedto reduce emissions of their products, although the measured emission profilesdon´t reflect the real indoor air conditions.
Therefore, decision makers andrelevant stakeholders should put the focus on research on the above describedmissing link between product emission and IAQ, to slow down the overregulationof product emissions.