Acid copper chromate (ACC) Alkaline copper quaternary (ACQ) Copper azole (CA) Chromated copper arsenate (CCA) Copper-HDO Copper naphthenate Creosote Pentachlorophenol (PCP) Sodium Borate (SBX) Micronized Copper Quaternary (MCQ)
The incisions help the preservatives penetrate deep into the wood, especially if it’s hardwood like Douglas fir.
Note that the greenish tint can fade over time, so this isn’t a completely reliable way of determining if old wood was pressure treated.
Pressure-treated wood is typically made using pine, fir, or spruce trees. These are pleasantly fragrant if they’re untreated, but if they smell “off” or like chemicals, it’s a good sign they’re pressure-treated.
Pressure-treated wood can get slightly smaller as it dries, so it’s really hard to paint brand-new lumber because the paint will peel as the wood contracts and shrinks. If you do want to paint pressure-treated wood, wait until the lumber is totally dry.
For example, the fact sheet should clearly state if the wood was treated and the chemical that was used. It should go on to explain whether or not it’s safe to burn the wood, and what safety precautions you should take when cutting or handling the wood.
Unfortunately, wood test kits only test for arsenic. To buy a wood testing kit, check local hardware stores, lumber yards, or online.
