A security category is a designation given to an airport to mark the amount of traffic flow, security strategic importance and personnel need. If an airport has high traffic, a large amount of commerce or hotels or major infrastructure such as dams, military bases or historical landmarks, the chances of an airport going into a higher category increases. Traffic flow is also a major determining factor, an airport in a large city will have a higher category while an airport in a small city with a population of less than 100,000 is likely to have a low category number.
Airports with this category designator has achieved 100 percent Advanced Technology X-Ray screening at all lanes at all check points, for example, DEN – Denver International Airport (www.tsa.dhs.gov). Such airports are required to have all resources available to them. Airport Police, Aviation Administrators and the personnel and equipment required to detect explosives are required to be readily available at any time and required to have a high level of staffing.
Smaller communites near large cities (such as Ontario, Calif) are often given a category I designation. These airports, as the category X airport are required to have all resources available, but do not necessarily need have them available on demand. A staffing shortage could result in a delay of staffing, but all the services need to respond to and prevent security breaches is available, but may not be readily available.
Small communities are sometimes given a category II designation. This designation is given to a lower amount of traffic than one would see at a category I. Some resources may not be available at the airport and have to be sent in from the city. Bomb sniffing equipment and heavy weapons may not be available to the police at these airport and any situation requiring these means that the SWAT team would have to be called in from the city. Staffing emergencies are more likely at these airports and the security checkpoint can not guarantee that an officer of the same gender is available.
Small Communities (such as Grand Junction, CO) are sometimes given a category III designation. This is given to communities too far from large airports to be of any large interest as a potential target. These communities often do not have the resources to cope with severe attack and heavy staffing of security personnel is not required. As with category II airports, personnel of both genders is not always available.
Any city that flies into a category X, I, II or III airport is required to have security screening no matter how small that airport is. Category IV airport are the smallest airports. Category IV Airports often only have 1 security lane (while other airports may have several) and may have fewer than four gates for airplanes to fly into. Category IV airports often have no special secured areas. Airports in this category are about the size of a municipal airport.