There are three distinct groups of Volatile Organic Compounds (VOCs). These differences are based on the boiling point of each chemical. They include VVOCs (Very Volatile Organic Compounds), VOCs (Volatile Organic Compounds) and SVOCs (Semi-Volatile Organic Compounds). Some chemicals, for example, Formaldehyde & Acetaldehyde more accurately fit within the VVOC grouping, whilst chemicals including Benzene, Toluene and Xylenes fit more accurately within the VOC grouping.