AS 4073-1993 pdf free.Urea-formaldehyde foam thermal insulation – In situ set foam.
Urea-formaldehyde foam thermal insulation is produced on site and installed directly into buildings in a wet state. It dries over the following weeks. This Standard specifies the properties which such foam must meet if it is correctly formulated and produced.
The foam generated in the gun shall be fully expanded before placement in the building and, while mobile at the time of placement, sets within a specified time and then dries by diffusion and evaporation.
The properties of the set foam can he determined by this Standard on samples specially produced during placement operations at the building site.
AS 4073 specifies the properties of set urea-formaldehyde foam (set foam) made by using phosphoric acid as catalyst. and produced for herrnal insulation purposes.
3 PEFINITIONS For the purpose of this Standard, the definitions given in AS 1886 and AS 2352 apply.
4 MATERIALS Raw materials used to produce the set foam shall be tested as described in AS 4074 and when combined and reacted shall produce set foam to meet the requirements of Clauses 5. 6 and 7 of this Standard.
5 THERMAL RESISTANCE When tested at a mean temperature of 25°C in accordance with either AS 2464.5 or AS 24M.6, thermal conductivity shall he not greater than 0.036 W/m.K. The test specimen shall be obtained in a plastic bag from a sample produced from the injection gun at the building site, transported to the laboratory, conditioned at 23 ±2°C and a relative humidity of 50% for 4 weeks, then further dried at 40°C for 48 h and cut to the required size.
6 PROPERTIES OF SET FOAM Methods of determination and properties of the set foam shall inee the requirements in Table 1.
7 COMBUSTION CHARACTERISTICS When tested in accordance with AS 1530.3 the dry-set foam shall have the following indices:
(a) Spread of flame: not greater than 7.
(b) Smoke developed: not greater than 7.
The specimen for testing shall be 50 mm thick and shall be produced as in Clause 5.AS 4073 pdf download.