The Monmouth Ocean Hospital Service Corporation (MONOC) operating in New Jersey has released a short video that can be viewed and downloaded from their website.
The video briefly summarises United States EMS crash statistics and goes on to discuss the benefits of a tiered response. The video includes a simulated lights & sirens response down an urban street that clearly demonstrates how soundproofing in modern vehicles along with background cabin noise from the car radio and air conditioner mask the siren sounds of an approaching emergency vehicle. The test vehicle is stationary and the ambulance is travelling at 25 mph but the video notes that wind and road noise produced by an average subject vehicle at speed reduces siren penetration even more than shown in the demonstration.
The video can be viewed on the MONOC website or downloaded free of charge as a Windows, Quicktime or iPad file (up to 300MB depending on format).
View and download the video – HERE
View the MONOC website – HERE
Read more siren reports from the AV Reference Library – HERE
Read another blog post on sirens – HERE
Ambulance Visibility Blog 
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