Frontline ambulances are very specialist and complex vehicles. They carry essential items of clinical and diagnostic equipment that can provide life-saving treatment to patients and also transmit ‘real time’ information to the hospitals regarding a patient’s condition. Vehicles also require advanced tracking and mobile data technologies to ensure ambulances can be on scene within minutes of a 999 call. All this equipment requires significant power from the batteries on board. Failure to keep these batteries fully charged can result in equipment not working correctly or at worst shutting down which may pose a significant threat to lives. In order to keep the battery charged the vehicle must be left running during some periods of rest.
Ambulance engines may also be left running to ensure the patient compartment, medications and equipment remain at a regulated temperature. In many cases patients are on board requiring urgent medical attention. During this time, regulated power supply to all medical and diagnostic equipment is critical. Turning the engine off may result in a break to the real-time diagnostic information feed into the hospital or vital patient life support systems failing.
Vehicles can often be seen idling on the roadside or at a scene for the reasons identified above. If a power supply is not available, regular charging is required by keeping the engine running. Idling also allows for a rapid departure from a scene.
In cold weather, leaving an ambulance running allows the diesel engine to operate more efficiently. When vehicles are on station, they do not need to run their engines as they are plugged into charging units that ensure the vehicle maintains a state of readiness.
The Welsh Ambulance Service is going greener and has introduced more eco-friendly vehicles into our fleet, replacing some of our older diesel-powered vehicles. We are committed to continuously reducing our carbon footprint and we regularly review systems and practices to ensure this happens.