Code of Practice for Selection, Operation and Maintenance of Special Fire Fighting Appliance, Part I: Combined Foam and Co Crash Tender
1970 Edition

Key operational procedures for combined foam and CO2 crash tenders per IS 5896 Part 1 include multiple modes of operation using water from onboard tanks, open static supplies, or water tenders. These modes cover foam production, foam and foam-fog discharge, water jets or fog, first-aid hose reel use, continuous operations, and refilling tanks. Operators must open the heat exchanger by-pass valve during foam use and flush the heat exchanger circuit thoroughly with clean water afterward to prevent damage. Adhering to these steps ensures efficient firefighting and prolongs equipment life.

As per IS 5896 Part 1, carbon dioxide cylinders must be weighed monthly. If a cylinder exhibits a loss exceeding 10% of its contents, it should be replaced with a fully charged one. Additionally, CO2 hose-reel tubing must undergo hydraulic pressure testing every six months at 7 MN/m² (70 kgf/cm²) for 2.5 minutes. Maintaining at least one fully charged spare set of cylinders per crash tender is advisable, with additional spares depending on availability of recharging facilities.

To keep crash tenders ready for operation, IS 5896 Part 1 recommends thorough maintenance after each use involving foam, water, or CO2 discharge. This includes draining foam tanks, flushing and drying pumps and hoses, cleaning foam monitors and heat exchanger circuits, replenishing water, radiator, and fuel tanks, and checking lubricating oil levels. Daily routines involve cleaning vehicle surfaces, lubricating controls and valves, inspecting hoses and bodywork for damage or corrosion, and verifying CO2 cylinder integrity. Periodic checks every six months include deep-lift and vacuum testing of pumps and hoses, pressure testing hose reels, servicing air blowers, and foam transfer pumps.

IS 5896 Part 1 mandates that water for firefighting at aerodromes be stored in static tanks capable of supporting two fire appliances each drawing 3200 liters per minute for 30 minutes, resulting in a minimum tank capacity of 192,000 liters. Tanks must be situated within 100 meters of the hazard, or 50 meters for high-risk locations like oil depots, and allow refilling within 18 hours. Access roads and hard standings must accommodate crash tenders. Water from these static supplies can also be used for foam production during extended firefighting or drills.

Operators should ensure the pump is engaged and the water tank suction valve is open before starting. For open static water supply, the pump must be primed. Delivery outlet valves for monitors and side-lines should be open, and foam compound flow selectors set correctly to generate quality foam. For CO2 discharge, the safety peg on the cylinder discharge head must be removed, and main and shut-off valves opened. CO2 hoses should be pulled out sufficiently before actuating cylinders one at a time. After operation, all foam equipment and hoses must be flushed with clean water, and foam compound tanks topped up if not scheduled for cleaning. Following these precautions ensures safe, effective firefighting and reduces operational errors.