For decades, vehicle soundproofing technology has gone largely unnoticed. However, it was always present, from insulating foams to rubber strips, reaching more complex materials and active sound cancellation systems in modern times. Isolating exterior noise from the cabin has been a concern of many engineering departments, and there are currently vehicles on the road that are actually soundproof cabins.
Sure, it’s nice to be traveling in a cloud isolated from the rest of the world, but it’s also a problem, mainly for emergency services. According to an NBC report, new cars are so quiet that drivers have a hard time hearing ambulances and fire trucks.
To address the problem, some US emergency departments are trying to adapt by operating two sirens simultaneously or using new booming sirens, which send out vibratory pulses that are felt by touchAlthough mid-range and high-end cars are usually immune to vibrations thanks to more sophisticated damping schemes.
Added to this, there is also the problem of vehicles that have active sound cancellation, that is to say, roughly speaking, that they have microphones that capture external sound and that generate the inverse sound through the speakers to cancel it out. Unless the system is well developed, many times it can happen that the noise cancellation also cancels the sound of some sirens, and this can be a very serious problem.
Not hearing sirens means drivers must remain alert and responsive in order to yield to emergency vehicles, and in many cases, creating delays and wasting valuable time that can save lives. All this without counting on several occasions these vehicles go with the siren on going through red lightsso not listening to them can result in a very serious accident.
Perhaps in the near future we will begin to have solutions from the vehicles themselves, with the so-called “Internet of things” warning each driver that an emergency vehicle is approaching through light or sound signals inside the passenger compartment.
