Alkyldimethylbenzyl ammonium chloride (benzalkonium chloride) (BAC) and alkyldimethylamine acetates were approved by the Timber Preservation Authority of New Zealand in 1978 for the protection of radiata pine that was destined for above ground, weather exposed applications. As a result of continuing failures, the use of AACs was stopped in New Zealand in the mid 1980s. The Plywood Association of Australia (PAA) was interested in the use of AAC wood preservatives because the preservative could be used to treat veneers before gluing without affecting the glue-bond strength. Treating the veneers also leads to a more uniformly treated product. A field exposure trial of AAC treated plywood using plywood treated to much higher levels than those used in New Zealand, was established in November 1992. The exposure was assessed annually for three years, after which time a limited approval was granted for use under the Timber Utilisation and Marketing Act (TUMA) of Queensland. At that time, there was no approval for use of BAC in the Australian Standard AS 1604. Assessment of the trial was suspended until mid 2001, nine years and seven months after initial exposure. All panels in the exposure were reassessed at this time and the results indicate that the BAC, used at the higher retention provided good protection for weather exposed, out of ground contact applications.

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