ACQ and CCA – How to Build Decks Safely
Chemicals in the Pressure Treated Lumber can literally make you ill for the rest of your life. Below are links to EPA and News articles to help you do the simple things needed to stay safe.
Today: Alkaline copper quaternary (ACQ) is a preservative made up of copper, a fungicide, and quaternary ammonium compound (quat), an insecticide which also augments the fungicidal treatment. Since it contains high levels of copper, ACQ-treated timber is five times more corrosive to common steel, according to American Wood Preservers Association (AWPA) test results. It is necessary to use double-galvanized or stainless steel fasteners in ACQ timber. Use of fasteners meeting or exceeding requirements for ASTM A 153 Class D meet the added requirements for fastener durability. The above paragraph from Wikipedia.
Future (already on the market): MCQ or Micronized Copper: The MCQ is a variation on the copper/organic formulations. Instead of using dissolved copper preservative, small particles of copper (called ‘micronized copper’) are injected into the wood. Wood treated with micronized copper is less corrosive to metal fasteners. It is still important to use approved fasteners with micronized-copper treated wood but aluminum can be used in contact with the treated wood.
Prior to 12/31/2003: Pressure-treated lumber contained a potent chemical called CCA, which stands for chromium, copper and arsenic. Chromium and arsenic are heavy metals known to cause cancer. They are also among the most toxic substances for people and animals.
Use Caution when demolishing older structures and take note of the CDC’s recommendations when cutting or installing any Pressure Treated Lumber. Do not breath in any sawdust and keep sawdust off your body and out of your clothes. See below for more information.
Note: Brazilian Decking and Lumber use no chemicals. It is wood directly from the forest. Specifically, Ipe Decking, Jatoba Decking, Cumaru Decking nor Tigerwood Decking, have any of the problems listed below.
Safety Recommendations from the CDC http://www.epa.gov/oppad001/reregistration/cca/safetyprecautions.htm
USA Today Report http://www.usatoday.com/news/nation/2003-12-29-treated-lumber_x.htm