If the goal is to meet Florida SCTL residential guidelines for land application of recycled materials, the amount of arsenic-treated wood (either as CCA or ACZA
) that can be commingled with untreated wood must be less than 0.05 percent, which is less than 1 pound of arsenic-treated wood per ton of wood processed.
These years-to-failure estimates bode well for the durability of wood products treated to standard retentions with the current ACZA
formulation, considering that the standard retentions for critical members are greater than those evaluated in the current study.
Ammoniacal copper zinc arsenate (ACZA
) was developed in the early 1980s as an improvement on ammoniacal copper arsenate (ACA) which dates back to the 1930s.
Migration of metals from Douglas-fir lumber treated with ACZA
or pentachlorophenol using best management practices: Preliminary tests.
Southern pine samples were treated with chromated copper arsenate (CCA) and Douglas-fir samples were treated with ammoniacal copper zinc arsenate (ACZA
), to target retentions of 0, 9.6, 16, 24, 40 kg/[m.sup.3] (0, 0.6, 1, 1.5 or 2.5 pcf) as determined by weight.
Two incision densities (660 and 800 incisions/[ft.sup.2]), four incision depths (0, 5, 7, and 9 mm; 0, 0.2, 0.28, and 0.35 in), and three preservatives (CCA, ACZA
, and ACQ-B) were evaluated (Table 2).
Literature review and assessment of the environmental risks associated with the use of ACZA
treated wood products in aquatic environments.
Another waterborne preservative, ammoniacal copper zinc arsenate (ACZA
), is commonly used on the West Coast and in other areas when specifiers request wood species that are difficult to treat.
The waterborne preservatives include ammoniacal copper zinc arsenate (ACZA
), chromated copper arsenate type C (CCA-C), alkaline copper quat (ACQ) types B, C, and D, and copper azole (CAB-A, CAB-B).
The bags were wired shut and transported to local treatment plants, where they were commercially treated with copper-8-quinolinolate (oxine copper, CU-8) in light organic sol- vent to the aboveground target retention level of 0.32 kg/[m.sup.3] (as Cu), chromated copper arsenate Type C (CCA), ammoniacal copper zinc arsenate (ACZA
), or ammoniacal copper quaternary, Type B (ACQ) to the ground-contact retention level of 6.4 kg/[m.sup.3].
(2000) collected rainwater from end-sealed deckboard specimens that had been treated with CCA Type C (CCA-C), ammoniacal copper zinc arsenate (ACZA
), or ammoniacal copper quat Type B (ACQ-B) and exposed for 1 year in western Oregon.
Known under the trade name Chemonite[TM], it was modified by replacing some of the arsenic with zinc in the 1980s; this formulation is known as ACZA
. Because ACA and ACZA
are alkaline and imbue the wood with vivid color, they have generally been used for industrial products and are used to treat refractory western conifers.