Hardware costs and manpower costs
X-ray detectors for baggage are not cheap. Most appropriate for schools is a single-energy unit (one radiation source) costing about $30,000. There are much more expensive models on the market, ranging from $250,000 to $1 million, but these are used in applications concerned more with the detection of explosives. The detection of drugs is also possible, but the sophisticated equipment needed is too expensive for most schools. Schools will generally use a black-and-white monitor with the x-ray machine. Some models add the convenience of a color monitor, which may not add any valuable information to be used in decision making by the operator. Again, costs limit most schools to black-and-white monitors.
The conveyor belt needed to feed items into and out of the x-ray detector will generally be priced as part of the total system cost.
The manpower cost for operating this equipment is very high. For low-volume applications, in which baggage comes through slower than one bag per minute, one full-time operator will be sufficient to help with the placement of bags on the conveyor belt, operate the controls, view the monitor, make a judgment regarding each bag, and perform any needed manual searches. However, it is generally recommended that one operator work at the monitor of an x-ray machine no more than 2 hours at a time and preferably no longer than one-half hour at a time, trading tasks with another security person.
Most high-volume facilities, including airports and schools, will have two operators assigned to each x-ray detector. In this way, the operators can switch off the task of watching the monitor and of performing manual baggage searches as required. Airports will normally give these operators a break every 2 hours because of the intensity of the work, but most schools will not be engaged with intensive baggage scanning for more than 2 hours.
For schools, it is not the length of time an operator has to work that is of concern; rather, the issue is the number of operators needed during a relatively short period of time and the number of x-ray units required to maintain an adequate throughput during the morning rush. While it is probably a simple matter to hire one security aide to work 8 hours a day, it is much more difficult to find eight security aides to work 1 hour a day. (Eight or more security personnel would normally be required to support the equipment and processes in a complete weapon-detection program at a school with 2,000 students.) For this reason, it is not unusual for a school administration to use fellow administrators, teachers, and other employees to supplement the security personnel running the equipment each schoolday morning. Employees may be pleased to earn the extra money, but the administration must be certain that all receive adequate training.
Who will run the equipment the other 7 hours of the schoolday? This can be expensive and a somewhat low payback effort. An approach implemented by some schools is to enforce a policy that the school doors are basically locked one-half hour after school begins in the morning. Although this is a rather harsh stance, it may be necessary in a school where resources are limited but the threat of weapons is quite high.
Vendors will normally provide initial training at no additional expense. A 4-hour course will adequately introduce a new operator to the overall use and safety information of an x-ray detector, but practice and experience is equally important. Interesting training aids are currently available from some vendors. Prepared images of baggage going through the x-ray scanner can be played back on the TV monitor for operator practice. Another feature on some equipment will randomly superimpose the image of a suspicious (but fictitious) item over the actual images being captured during the normal work time. These phantom images may help operators to stay aware so that they are not lulled into complacency by the routine absence (hopefully) of any weapons coming into a facility.
Research Report: The Appropriate and Effective Use of Security Technologies in U.S. Schools