In 2005, the New York City Police Department (NYPD) asked DOE to conduct a survey of the New York City metro area. NYPD officials were aware that DOE had the capability to measure background radiation and locate hot spots by helicopter because DOE used this capability at the World Trade Center site in the days following September 11, 2001. DHS provided the city with about $30 million in grant money to develop a regional radiological detection and monitoring system. NYPD decided to spend part of this money on a complete aerial survey of all five boroughs. DOE conducted the survey in about 4 weeks in the summer of 2005, requiring over 100 flight hours to complete at a cost of about $800,000.

According to NYPD officials, the aerial background radiation survey exceeded their expectations, and they cited a number of significant benefits that may help them better respond to a radiological incident. First, NYPD officials said that in the course of conducting the survey, they identified over 80 locations with unexplained radiological sources. Teams of NYPD officers accompanied by DOE scientists and technicians investigated each of these hot spots and determined whether they posed a danger to the public. While most of these were medical isotopes located at medical facilities and hospitals, according to NYPD officials, awareness of these locations will allow them to distinguish false alarms from real radiological threats and locate a radiological device more quickly. Second, NYPD officers are now trained in investigating hot spots and they have real-life experience in locating radiological sources. Third, NYPD officials now have a baseline radiological survey of the city to assist with cleanup efforts in the event of a radiological release.