HTX worked with SCDF to improve the safety of our firefighters.
The previous and updated ways of unloading the CAF backpacks. (Photo: HTX)
Imagine you’re a firefighter. You’re well-aware that every second counts in saving people from a fire. Upon reaching a fire scene in your Light Fire Attack Vehicle (LFAV), you and your fellow firefighters quickly assemble your firefighting equipment, including Compressed Air Foam (CAF) backpacks.
As CAF backpacks are more effective in putting out fires than fire extinguishers, you rush to quickly don one and get to the fire. However, each CAF backpack can weigh up to 25 kg, so you need to be very careful in doing this! Given the weight of the CAF backpack, putting one on with the incorrect posture may cause musculoskeletal injury.
To improve the safety of firefighters donning the CAF backpacks, Lead Scientist Dr Deng Rensheng, Deputy Director Dr Saravana Kumarasamy, and Engineer Xu Yuan Xing from HTX’s Human Factors & Simulation Centre of Expertise collaborated with SCDF’s Rota Commander LTA Syed Yazid Bin Syed Nasiruddin from Tuas Fire Station, HazMat Specialist WO2 Nur Irwan Bin Abu Bakar from Banyan Fire Station, and HazMat Specialist WO1 Md Erwandy Bin Md Ali from Alexandra Fire Station to redesign the CAF backpack retrieval system and enable firefighters to carry out their mission safely.
The previous way of unloading a CAF backpack required the firefighter to lean forward into the rear cabin of the LFAV, retrieve the backpack along an upward slope to the edge of the cabin, bend down to don it, before adjusting it to a comfortable position. On the earlier method, Rota Commander LTA Syed Yazid said, “acquiring and donning the CAF backpack required two individuals for efficient handling. When done alone, the process was time-consuming. Bending over to wear it may also cause strain on the back.”
After studying how firefighters retrieve CAF backpacks, the HTX-SCDF team found that the system could be made safer by installing a sliding tray at the rear compartment of the LFAV. This sliding tray allows the CAF backpacks to be stored at the firefighter’s waist level, significantly reducing the need for bending, twisting, or lifting. By simply sliding the backpack out and tightening the straps while it rests on the tray, firefighters can proceed to fire sites without further adjustments, thus mitigating the risk of musculoskeletal injury.
To determine the optimal height for the sliding tray, the team used digital human modelling (DHM) software to simulate the retrieval and donning process at different rear cabin heights.
The pilot trial of the redesigned system in four LFAVs showed over 95% satisfaction among firefighters, leading to its full implementation in February 2023. As LTA Syed Yazid shared, “The introduction of the sliding tray has significantly improved the process of deploying and donning the CAF backpack. This feature has enhanced the overall user experience, providing greater ease and functionality, while greatly reducing the risk of injuries and mishaps.”
Additional feedback from firefighters led to further enhancements such as installing strong gas springs and LED light strips, which were also incorporated in the final design.
The successful redesign of the CAF backpack retrieval system shows the effectiveness of the collaboration between the HTX scientists and engineers and the SCDF firefighters. As LTA Syed Yazid noted, “Participating in the study offered valuable insights into the user experience and the practical implications of using the CAF backpack. As frontline users, we recognised the direct impact our contributions could have on our daily operations.”
The research paper “System Redesign to Improve Ergonomic Safety — The CAF Backpack” can be found in the 2023 edition of SCDF REaction: Rescuers in Action, which is available for free download here.