What technique should you use when you need to slow down immediately?

The technique of pumping the brakes is effective for slowing down immediately, particularly in a vehicle like an ambulance where rapid deceleration is often necessary. Pumping the brakes helps to engage the braking system effectively without locking up the wheels, which can lead to a loss of control, especially on slippery surfaces. This method allows for maximum braking force while still maintaining steering ability because it prevents skidding.

Using this technique is especially important in emergency situations where maintaining vehicle stability and control is crucial. While options like shifting gears or pulling the emergency brake can alter speed, they don't provide the immediate and controlled deceleration that pumping the brakes offers. Additionally, accelerating would clearly not aid in slowing down and could result in dangerous situations.