Penta is the shortened name for the chemical preservative, Light Solvent Pentachlorophenol (Type C), which is dissolved in mineral spirits (a carrier) with a water repellent additive. Mineral spirits as the carrier evaporates rapidly producing a wood product that is clean and paintable.
Penta is an approved preservative in the AWPA (American Wood Protection Association) standards for poles, crossarms, posts, land and freshwater piling, ties and timbers, although the primary use for penta is in the treatment of utility poles. The production and use of penta is regulated by the EPA.
Penta Treated Wood & Health
Penta: A Cost Effective Choice
Trained, certified pesticide professionals recommend penta because of its proven ability to provide long-term protection against insects, organisms and the elements. Penta treated utility poles can deliver a service life of 60 years or more.