The primary function of a police siren is, of course, to ensure that people on the road are warned about the presence of a police car. Apart from this, there are many other functions and uses for police sirens both in everyday and emergency situations. For instance, the sound of a siren could mean that police officers are speeding through the traffic in pursuit of an offender. Different sounds of a police siren also indicate different kinds of scenarios, making sure that it calls the attention of the people both on the road and on the sidewalk.
If the police officers are just on a typical street or highway, they often use the wailing sound. But if they are traveling along a heavy traffic area, they usually use the siren sound that is piercer so that they can effectively alert the people by piercing through their senses. This is to make sure that they will clear the path for the police vehicle. The more advanced vehicles today can be outfitted with police siren that works with a howling sound at low frequency but can call the attention of vehicle drivers even miles away. This is to make sure that the drivers can clear the way in advance for the police car to take the route freely.
Moreover, there are other kinds of police siren that can be utilized to escort another vehicle like an armoured truck full of money. For regular civilians, the different sirens may sound very similar but for trained ears, they are not the same. The main purpose why police officers use different types of siren sounds is to affect the senses in various ways that regular people don’t know. However, despite the difference, all sirens are made to get the maximum attention of the pedestrians and drivers in case of an emergency and when in operation.