CCA (Chromium, Copper & Arsenic) treated timber poses serious health risks through physical contact and through leaching into waterways. Consequently, CCA treated timber has been banned from sale in the UK - since September 2006.

As an alternative, UC3 and UC4 treated timbers are frequently used for footbridge beam structures. Although substantial in profile, these treated timber beams often have a disappointing service life, with clients reporting bridges failing in as little as 5 years from installation date.

At Bison Bridges we have opted for the longer life solution of hot dipped galvanised steel beams. While the cost of steel beams is higher than the initial purchase price of timber, we can assure clients of a safe, maintenance free bridge structure that will last for many years to come!

Modern timber treatment classes:

• Use Class 3 (Coated): For external use above the ground when coated.
• Use Class 3 (Uncoated): For external use above ground where there is no coating.
• Use Class 4: Direct contact with soil or freshwater.