Eye on You
Oct 1, 2008 12:00 PM, By Paul Benne
Right-sizing today's security technology to better protect the next generation.
Many of today's movies and TV crime shows exaggerate the capabilities of mainstream security equipment. The 1998 thriller “Enemy of the State” is a case in point. It presents a video recording from a two-dimensional, stationary surveillance camera, which subsequently is manipulated by a secret government agency to produce 3-D, 180-degree footage of the same scene. This might lead security system users to expect their seemingly comparable stationary camera to achieve the same performance.
However, education institutions must hold realistic expectations of their systems and equipment. Schools and universities should make sure that those expectations are clear before a system is installed.
Specifying the right package
The first step in building an effective security system is to establish the overall security goals of a school or university. Creating a blueprint for how the security technology will be used and defining its internal communication methods — how data will be stored, and its compatibility with future upgrades and existing equipment — is crucial.
After setting goals, the next step is to gather information. What is the intended purpose of every piece of equipment? What areas need surveillance, and what exactly is to be identified? What are the threats inside the school, and outside in the community at large? Consider any relevant past events and the type of building that needs to be outfitted. Talk to teachers, maintenance staff and administrators, and analyze ways to monitor each space properly.
Finally, address any legal considerations. From a legal standpoint, when a facility expresses a level of apparent security, it is required to perform security in a reasonable manner. Sign-age is the most common expressed legal consideration and can play a significant role in effective campus security. Posting signs that read, “Premises under 24-hour surveillance, all activities are recorded” or “Security cameras in use” expresses a significant sentiment to those who view them. If an incident came under litigation, and an institution wasn't living up to the expectations raised by those signs, it could be exposed to liability.
Instead, a more appropriate sign would read: “Notice: Premises under surveillance, activities may be recorded for informational purposes.” This sign, unlike the others, expresses a benign indication of use and responsibility, but still may serve as a deterrent. A school would use this sign to express that it may record or use video taken for informational and not necessarily security purposes. This reaches the same objective without stating that the video is for security purposes only.
Facilities often imply some form of protective measure in normal daily operations as well. An implied expression is one that is made indirectly. For example, when a school installs a video camera, it is implying that some form of surveillance is being conducted. Perceptions (made up of personal experiences and knowledge) drive an individual's conclusions about the implied expressions; many automatically will perceive that a camera is watching, even without actual knowledge that it is. For example, most bank patrons perceive that their financial institution records activity continuously, even if they never see a camera.
Selecting the right equipment
After defining a school's security goals, gathering information from officials, and considering the legal parameters, administrators must choose appropriate equipment.
A school should evaluate each device selected for its potential contribution toward security goals. For example, cameras are available in two basic styles: stationary and pan, tilt and zoom. Which will best meet the school's security needs? Will the cameras need to perform general or object-specific surveillance? Camera resolution and frame rate capabilities should be evaluated at this point as well.
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Resolution indicates the amount of lines or pixels of video information contained in each frame. This can be understood by comparing a high-definition television (HDTV) to a standard-definition television. The HDTV has more lines of resolution, thus producing a sharper, clearer image. The same applies to video-surveillance equipment; different applications call for different levels of resolution. For example, recording a high school hallway during a passing period will demand high resolution because of the elevated incident rate at that time. However, at night, the same resolution is not needed.
Using equipment effectively
Most digital surveillance cameras and recording systems can be programmed to automatically lower resolution when there is little or no activity. This saves video storage space. And if a camera does detect activity during a lower-resolution period, it can be set to automatically increase its resolution as needed.
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Frame rate is the amount of pictures a camera takes every second. The human eye views an equivalent of 30 frames per second (fps); similarly, TV and movies (i.e. full motion, real-time video) appear in 25 to 30 fps as well. But, security equipment typically doesn't record at such a high frame rate; that consumes a tremendous amount of memory. The higher a camera's frame rate and resolution, the greater its storage capacity must be, requiring more expensive infrastructure to support the recording demands.
Camera-recorded video typically is viewed in real time (30 fps), but is actually recorded at a slower speed in order to maximize video storage. An average public venue or school cafeteria will provide adequate surveillance by recording at only 5 to 7.5 fps at standard resolution. During an alarm event, however, with the simple push of a duress button, a camera can increase its resolution and recording speed to 30 fps in order to capture the moment in real time with greater detail.
One of the biggest school security issues is the lack of real-time information provided by surveillance equipment. Many schools install cameras and then watch an incident in hindsight.
To make schools safer, education security systems must be designed to respond to building conditions as events are actually happening. For example, video monitors should be programmed to call up and display cameras based on unusual or alarming activity. If a back door not used for building entry is opened unexpectedly, a camera should automatically position itself and display the area on a video monitor.
Justifying the expense
One way to keep track of multiple video displays is by using an audible alarm to draw attention to an activity being displayed on a particular monitor, alerting staff members to check the screen and determine if further action is needed. Also, installing duress buttons in high-incident areas allows the supervising staff to increase camera recording speed and simultaneously alert administration of a potential emergency.
In addition to obtaining and responding to real-time information, school employees must be trained to successfully navigate among cameras in different areas of the building and retrieve recorded video.
Where is video surveillance allowed?
Schools should conduct systems testing monthly and maintenance quarterly, so that deficiencies can be addressed before an incident occurs. Maintenance staff can use cameras for non-security purposes, too. For example, a supervisor can log in from remote locations to view school grounds and confirm that snow has been removed properly or that maintenance work is being done.
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