How the new preservatives stack up to CCA

THE TRANSITION away from

I CCA treated wood in residential applications means that over the coming months, many dealers, wholesalers and treaters for the first time will begin marketing the new generation of arsenate-free products.

The major preservative producers each have their own alternative to CCA. Chemical Specialties, Inc., introduced ACQ Preserve in 1993 using alkaline copper quat and by the first of 2002 had nearly 20 U.S. companies treating with the preservative.

Last year, Arch Wood Protection unveiled CBA (copper boron azole), which is used to produce Wolmanized Natural Select wood.

Osmose also has begun selling alkaline copper quat, but marketed under the brand name NatureWood.

Representatives of the three companies were in general agreement when asked to compare CCA to the new preservatives.

L. Are there any superficial differences between CCA treated wood and ACQ or CBA treated wood, such as color or smell?

As it ages, CCA-treated wood initially has a greenish-gray tint that fades to gray. ACQ and CBA{reated wood weathers to a brown, before fading to gray. A small difference, the chemical companies say, that few consumers will notice.

2. Lre use or handling requirements different than CCA?

The manufacturers recommend the same handling and use guidelines (wear gloves; wear a dust mask when sawing, sanding or machining; wear goggles; wear goggles when powersawing or machining; avoid pro- longed inhalation of sawdust, etc.), since they "apply equally well to all types of wood, treated or untreated, or any building product."

3. ,l.e fastener requirements different compared to CCA?

The same fasteners are recommended: quality rust-resistant fasteners, such as hordipped galvanized or stainless steel.

4. lre the warranties different than for CCA?

Wood treated with the new preservatives will carry the same lifetime limited warranties against termites and decay offered by CCA products.

5. Does selling ACQ Preserve, NatureWood or Natural Select. like CCA-treated wood, require any special labels, hang tags, signage or Consumer Information Sheets?

No, the end tags and signage introduced last yeat are unneccesary. The alternative preservatives are not restricted-use pesticides. Yet, the safety sheets contain pertinent advice that is still recommended to be disseminated in some form.

6. ttow does price currently compare?

Estimates are that at the retail level the alternative products could cost l5%o to 307o higher than CCA pressure treated wood. Price would also be influenced by the market price of the wood, the retention level and if water repellent was used.

7. Since the new preservatives are shipped to wood treaters in a less concentrated form than CCA, will more be required to treat the same amount of wood?

Most wood treaters currently receive CCA in a 50Vo to 60Vo concentrate. ACQ is shipped in a l4vo concentrate, CBA in a l57o to 20Vo concentrate. Therefore, treating the same volume of lumber would require three to four truckloads of chemicals instead of one. So, in addition to paying more for the preservative itself, treaters will also incur significantly higher freight charges.

Woodtreated with the new preservatives will carry the same lifetime limited warranties against termites and decay.

8. Witl Arch. CSI and Osmose continue to make CCA available after 2003 for commercial/industrial applications?

Yes.

9. A"" NatureWood, ACQ Preserve and Natural Select comparable?

The manufacturers agreed that their chemicals offer "basically the same benefits" and are "suitable for the same applications."

L0. I handful of smaller treaters instead are switching to ACC (acid copper chromate). How does it compare to the new preservatives?

Although the chemical is listed in the AWPA Standards, it is not widely used. No major preservative manufacturer currently produces ACC. It is a preservative that individual treaters can mix for themselves.