Remote area fire-fighting was a difficult and physical operation for a fire crew in the 1950s and '60s. Several methods used were ‘dry’ fire-fighting techniques using rake-hoes and shovels, and ‘blacking- out’ using a ‘hose relay’ system.
The smaller tanks, measuring approximately 600mm x 600mm x 800mm high, were fitted with eyelets at each corner that allowed them to be anchored to the ground and secured to trees or logs to retain their vertical shape (Figs. 3 & 4).
A small, lightweight 450 litre self-supporting portable water storage dam, manufactured from Ripstop PVC material, was also used for fire-line operations. The tank was fitted with PVC flaps complete with 25mm brass eyelets to provide an anchor point for securing the dam on side slopes. A PVC carry-bag housed the water storage dam and connecting valves for ease of transportation on the fire-line (Fig. 5).
The laden carry bag weighed a total of 10 kgs.
This paper sets out the history of Class A Foam use in Victoria, giving full details of equipment development and the advantages and disadvantages of the various approaches.
The nature of water makes its conservation difficult, since it evaporates, beads up and will not penetrate or stick to vertical surfaces. One method which assists with overcoming these difficulties is adding foam compound to the water.
In Victoria, from the mid 1950's until the early 1980's, water was treated with "wetting agent" to reduce the surface tension of the solution, and allow it to spread and penetrate fuels more effectively. Wetting agent plus water was known as "wet water". Wetting agent was available in powder form in cellophane packs from the mid-fifties, and as a liquid in more serviceable plastic packs from the mid-sixties. It was introduced directly into the water tank, then mixed in by vehicle motion or by pump impeller rotation. Although it was an advance over using plain water, "wet water" could not be made into foam. Also, pump priming problems due to cavitation were frequent. An improvement had to be found, and the answer lay in both equipment development and the introduction of Class A Foam.