In preparing this Standard, consideration has been given to comparable overseas Standards, to minimize duplication of effort and to maintain commonality, wherever reasonable, with those Standards. Particular consideration has been given to the various parts of BS 6920, Suitability of non-metallic products for use in contact with water intended for human consumption with regard to their effect on the quality of the water. Several of the test procedures and criteria given in BS 6920 have been adopted or modified for Australian and New Zealand requirements.

This Standard departs from BS 6920 as follows:

(a) This Standard provides a method of testing for the leaching of compounds that may produce a mutagenic effect.
(b) The requirement for products to be tested at surface area-to-volume ratios that are not less than those in the intended end-use exposure (with the exception of the test forgrowth of aquatic micro-organisms). Where there is a difference between test and end-use exposures, provision is made for a scaling factor to be applied to the test
result.
(c) The inclusion of testing for metals extracted from metal products that are often components of products in contact with drinking water.

Significant changes from the previous edition include the following:

(i) Inclusion of a colorimetric method for determination of cytotoxic activity.
(ii) Inclusion of an appendix on the structure of test reports.
(iii) Revision of the appendix on product submission information.
(iv) Altered requirements for testing non-metallic products for leaching of metals.

The terms ‘normative’ and ‘informative’ have been used in this Standard to define the application of the appendices to which they apply. A ‘normative’ appendix is an integral part of a Standard, whereas an ‘informative’ appendix is for information and guidance only.

Originated as AS 3855(Int)-1991. Previous edition AS/NZS 4020:2002. Fifth edition 2005.