Pacific Testing offers a range of external exposure sites.

The severe marine and arid sites have been chosen for the exposure of paints and other metallic coatings. The Corrosive site at Belmont and the Sunshine site at Birdsville are recommended sites for exposing prepainted metal products as specified in AS/NZS 2728 “Prefinished / prepainted sheet metal products for interior/exterior building applications – Performance requirements“.

These sites can also be used for testing all materials that rely on resistance to corrosion, colour-fastness and resistance to UV radiation, namely: paints, fabrics, carpets, packaging, dyestuffs, rubber, resins and adhesives.

Samples can be placed on fixed racks at 0°, 5°, 45° or 90° to horizontal.  Other angles can be catered for at customer’s request.

Severe Marine / Corrosion Site
Belmont Beach (NSW)

Latitude 33° 02’ S, Longitude 152° 40’ E, Elevation 8m

Located 20 km south of Newcastle and less than 200m from breaking surf, with corrosion rates of 200 µm/y to 750 µm/y for mild steel and 8-20 µm/y for Zn (depending on deployment factors), this site is one of the most aggressive in Australia.   Annual average chloride deposition rates ranges from 250 to 350 mg/(m2.d) as measured by ISO 9225:1992(E) but will seasonally vary from 40 to 675 mg/(m2.d).  Time-of-wetness is typically 5650 h/y (66%) but will also vary with seasons and prevailing winds.

Arid / Sunshine Site
Birdsville (Far West Queensland)

Lat. 25° 90’ S, Long. 139° 35’E, Elevation 47m

Birdsville is unquestionably one the most arid sites in Australia, approximately 1000 km from any ocean, on the edge of the Simpson Desert, combining almost the highest global radiation (~ 22 MJ/m2), the highest sunshine ( > 10 hrs a day) and one of lowest rainfalls (~ 165 mm/y) in the country.

Part of the township of Birdsville -Test site lower of centre. Rain-days per year average 22 – the lowest for any meteorological station in Australia. The annual daily maximum temperature averages 30.3°C with an average maximum temperature in January of 38.8°C. The highest maximum temperature of 51°C was recorded during February 2004. Typical diurnal temperature range is 20 °C throughout the year.

Surface temperature reached 61.3°C during February 2002 and dropped to -2.4°C during July that year. Corrosion rates are ~3 µm/y for coppered steel and 0.28 µm/y for Zn, some of which can be attributed to the erosive forces of wind-borne sand. Time-of–wetness is ~450h/y (~5%). This site is the most extreme AS1745.1 A3 classification available in Australia.

Specialised sites

Flying Fox Enclosure

We were asked to expose painted samples to the effect of bat droppings.  After some searching we located a flying fox rehabilitation centre on the NSW Central Coast and negotiated the placement of painted specimens underneath the feeding bins of the animals.

The bats were fed a special diet of mulberries for the course of the trial to ensure a constant “deposit” on the paint.