Formaldehyde is only one of thousands of compounds in the total volatile organic compounds or tVOC that is monitored by the QP Pro. It's important to note that the tVOC reading isn't solely indicative of formaldehyde levels. tVOC readings may increase significantly when there's increased occupancy or during activities like cooking, cleaning, or when substances containing alcohol are nearby. Sources of tVOC includecombustion products like coal or natural gas, tobacco, as well as materials used in construction, home decor, furniture, and household appliances. To mitigate tVOC levels, consider utilizing ventilation or air purification methods.