Kingspan Insulation has applauded the tightening of on Australian Standard on fire ratings for insulation materials but called for another to be replaced by a more stringent model.

Australian Standard AS/NZS 3837–1998 has been amended to prevent certain types of insulation materials from gaining top fire ratings based on ‘small scale’ test results.

AS/NZS 3837 stipulates fire test procedures for certain materials and products using a 100 mm diameter sample in controlled conditions.

However according to Keith Anderson, Technical Manager at Kingspan Insulation, some insulation products made from thermoplastic materials like polystyrene were achieving high ratings using the AS/NZS 3837 test by virtue of their reflective facing, even though they would not perform well at all in a large scale fire situation due to their burning and melting characteristics.

The company says some manufacturers were using inappropriate AS/NZS 3837 results to obtain high ‘Group Number’ product performance ratings, as required by the National Construction Code (NCC), to validate the approved use of their products as exposed linings in buildings.

Anderson has praised the adoption of the recent update (Amendment 1) to AS/NZS 3837–1998, which states that products and materials that melt or shrink away from flames cannot be tested appropriately by this test method. It also prohibits the use of data from the AS/NZS 3837 test method to calculate Group Number classifications for these kinds of inappropriate products and materials.
He says the industry should be aware that some insulation products such as Kingspan’s Kooltherm K10 FM still qualify for (the highest) Group Number 1 status, based on  testing of the components of the product, including  the rigid thermoset core material unfaced and unprotected by the foil facing.

“The core material is very important for fire safety in these materials”, he says.

Call to replace AS 1530.2–1993

Anderson says the separate Australian Standard AS 1530.2–1993 should be abandoned as a tool for measuring reflective insulation membranes, known as ‘sarking-type materials’ in the NCC, and replaced with a more representative test, BS 476 Parts 6 and 7.

“AS 1530.2 is inappropriate and inadequate for testing synthetic reflective insulation membrane products such as our Air-Cell range and similar products – after all, this Standard was originally designed to test things like fabrics, curtains and drapes,” he argues, “and it is clearly unsuitable for materials that shrink and melt away from the flame, as stated in the scope of the test method”.

A superior alternative, he claims, is BS 476 Part 6 and 7, which is widely used in the UK, Europe, Middle East and Asia.

“I urge all other Australian industry stakeholders to support a push for this important reform in Australian fire safety testing standards.”