Operating Procedures
The information about Operating Procedures is provided here as a guidance only to compliment and not to replace procedures and guidelines used at your own locality/facility.
- Before operating an X-ray machine, a formal testing programme of safety measure checks should be undertaken to ensure that all radiation shielding components and safety devices, including interlocks, switches, warning lights, and indicators are installed and functioning. The Emergency OFF switch should be in released OUT position and no objects should be in the inspection channel. All service panels should be closed and locked, without any signs of damage that could compromise barrier protection; and all warning signs should be legible. Check the unit for any sign of damage to the housing panels, monitors, keyboards and visible cables.
- If an X-ray machine is operating constantly, the aforementioned formal testing programme of safety measure checks should be carried out at least once every 24 hours.
- If any of the tunnel curtain flaps are missing or damaged, report the fault. Some machines may still be safe to operate with one flap missing, but you should confirm this with your supervisor. If two flaps are missing, do not operate. Also look out for tears/damage in the curtains.
- Check the conveyor system of your X-ray unit for tears and dirt in the conveyor belt or the driving chains and rollers, as well as for items caught in the conveyor system. Tears, especially on the edges of the belt can lead to major damage.
- If any of the X-ray machine panels are loose, punctured, dented or missing, do not operate the machine. Report the fault immediately. Never attempt to remove surface panels from any X-ray machine.
- X-ray equipment must be so arranged that the operator who initiates the X-ray exposure must be in a position where he can readily observe all ports and doors during generation of X-rays. In the case of equipment in which the X-ray beam is activated by an automatic device, this requirement should be met by the primary viewing position for the X-ray image permitting all ports and doors to be readily observed during generation of X-rays. Operating an X-ray screening point is very much a team effort. Communication between all personnel in the screening operation is vital in order for it to operate effectively.
- Adjust the monitor screen for maximum efficiency and ensure you are seated comfortably at the correct viewing height. Take care not to catch any parts of the body when moving the operating unit.
- Never touch the conveyor belt when the machine is operating, or lift the lead drapes for any reason when the x-ray beam is on, or expose any part of the body to the x-ray beam, or cover the x-ray ON lights or x-ray warning signs.
- Never reach inside the unit when the X-ray is operating, or let anyone else do it.
- It is important that all bags loaded onto the conveyer are loaded in the “optimum position” in order to obtain the best image for the X-ray operator to scrutinise. Bags should initially be loaded in the flattest position possible, one at a time. In order to identify unknown objects, bags should be rescanned at different angles. In order to assign X-ray images to scanned baggage, you should keep an appropriate distance between the subsequent items.
- Bags should be loaded far enough apart to allow sufficient time to screen each item. Allow the lead safety curtains to drop back into position before another item is loaded. When scanning items which have been very close to one another, the image quality will become reduced after some time. Therefore keep items correctly spaced to optimise image quality. The image of a subsequent baggage item will remove the image of the previous item from the screen. Therefore the time to evaluate the image is limited. If a longer period of time is required, you must stop the conveyor.
- You should not continuously monitor images for periods longer than 20 minutes in any hour.
- If the conveyor is stopped manually or automatically though the inspection of a baggage item has not finished, the conveyor may possibly reverse a short distance automatically. This prevents cuts in the X-ray image. In this case, pay attention to baggage items which have been placed at the entrance side of the conveyor during the stop. These items could fall down when the conveyor is reversed.
- Very flat items, liquids, dirty items, items equipped with slack belts, or items with damaged packaging, etc., should always be put into appropriate plastic containers before being X-rayed.
- Never interfere with baggage on the conveyor belt, even if a jam occurs. Press the conveyor STOP button, remove the key and then rectify. If a person or item is becoming trapped in the machine, press the Emergency STOP button E-STOP immediately.
- Obviously, a baby should never ever be left in an infant carrier while it goes through an X-ray machine. In 1988, an infant in a car seat went through an X-ray machine at Los AngelesInternational Airport. Also that year, screeners at Winnipeg International Airport inCanada accidentally sent a 2-month-old wrapped in blankets through an X-ray machine. In December 2006 a woman put her month-old grandson into a plastic bin intended for carry-on items and it went through the X-ray machine at Los Angeles International airport. So to prevent serious incidents like these occurring, an X-ray machine’s tunnel entrance must be supervised at all times to ensure that a parent cannot inadvertently place an infant in a cot or carrier onto the conveyor belt.
- Children must be removed from strollers and infant carriers, so that these can be collapsed ready to undergo visual, physical and X-ray inspection. All baggage, including children’s bags, should be put through the X-ray machine, including all child seats, baby carriers, nappies, diapers, bags, blankets, toys, etc., – anything that is carried onto the plane or into the high-security facility. Make sure all bags hanging on and slung under child-related equipment are removed from the equipment and put through the X-ray machine.
- If an item is too light to push aside the tunnel flaps, stop the conveyor and push the item past the flaps. Never push an item through the flaps by hand when the X-ray system is operating.
- If you need to put a delicate or fragile item through the X-ray machine, you should put it in a tray or ensure that there is no baggage immediately before or after the item so that it will not be damaged. If it is a particularly delicate or valuable item – or a sensitive religious, cultural or ceremonial item – you should conduct a hand-inspection if this is requested. You should also perform a hand inspection of photographic film and extremely sensitive electronic equipment such as Braille note-takers, if the owner fears that X-ray could damage them.
- All equipment like crutches, sticks and walkers should go through the X-ray machine, or be carefully visually inspected.
- Always inspect a person’s shoes, and ask the person to remove their shoes, and pass them through the X-ray machine if there are any suspicions. In a past incident a terrorist Richard Reid, known as the Shoe Bomber, attempted to explode an IED concealed in his training shoe on board an aircraft.
- If a bag is selected for search, the owner should be requested to open the bag. This will allow you to see if the person appears familiar with the bag and its contents. Perhaps the person may become nervous, uncooperative or hesitate, which may indicate that it is not their bag, or that they may know the bag contains something illegal or dangerous. When an item has been hand searched it is important that the searcher informs the operator of what the object was that caused the rejection.
- Make sure members of the public follow safety instructions, and ensure they do not spend time around the x-ray inspection system longer than is warranted.
- Every baggage x-ray inspection system should be located in such a way that under conditions of use, individuals whose baggage is to be screened with the x-ray inspection system must be more than 1 metre away from the access openings of the irradiation chamber while the x-ray beam is on. Members of the general public, excluding staff authorised to work with the systems and those individuals whose baggage (or belongings) is to be screened, must be more than 2 meters away from the x-ray inspection system.
- Never engage in conversation or become distracted by anything, when operating an X-ray machine. Always bear in mind that an unusual item in a bag may be intended as a diversion – to draw attention away from a smaller true threat concealed in the same bag. Do not get distracted from evaluating a whole image by some easily recognisable details. Pay as much attention to framework and appendages of baggage as to the contents.
- Never work under time pressure when evaluating X-ray images. Security depends decisively upon your work. Stop the conveyor if you do not have time to evaluate any image properly. Always be aware that your X-ray unit does not automatically detect dangerous items.
- Dark objects, which cannot be brightened up with image enhancement features always need a manual check. Dangerous objects may be hidden behind. Always reject anything that cannot positively be identified.
- Report anyone who seems to be taking an unusual interest in your organisation’s security system, as terrorists have been known to carry out “practice runs” on a facility prior to an actual attack. Remember, the 9/11 terrorists visited several airports prior to their attacks, to study the organisation and proficiency of the security regimes. Terrorists and saboteurs will generally carry out a reconnaissance of potential targets for whatever type of operation they are planning. An unprotected target is more likely to be attacked than a better protected one and terrorist groups will often be deterred by visible security arrangements and procedures which are seen to be effectively conducted. An installation whose personnel are obviously vigilant is less likely to be selected as a target for a terrorist attack than one with personnel whose security procedures are neither comprehensive nor diligently enforced.
- X-ray equipment should only ever be moved by qualified personnel using integral wheels; or forklifts, or lifting jacks. Radiation leakage can result from damage through mishandling. If an X-ray machine is ever bumped or jolted, it should be examined for radiation integrity by qualified staff before being operated.
- Machinery which is not radio-screened or walkie-talkies can interfere with the X-ray unit. Don’t operate machinery which is not radio screened in the vicinity of an X-ray unit and don’t put walkie-talkies onto the unit or let others use them within 1 metre of the unit and the monitor.
- Don’t put metallic objects, including keys onto the unit. They can damage it.
- X-ray machines should never be left unattended in an operational mode. For operations not requiring constant user supervision or surveillance, the X-ray machine must be adequately secured to prevent tampering by unauthorised individuals.
- When shutting down your X-ray machine, the unit will still remain active for a short period until it shuts down. During this time, the power-on indicator will be illuminated.
- If, for some particular reason, your X-ray unit is to be completely disconnected from the mains supply, you must wait until the power-on indicator has extinguished before withdrawing the mains plug or deactivating the mains supply. Failure to do observe this procedure could severely damage your equipment.
- It is not possible to provide guidance in this presentation for all scenarios that could cause unsafe events. When unusual events occur, always shut down your operation immediately and inform your Supervisor.
In some airports, passengers are offered a choice of screening environments. Frequent travellers, known as ”expert” travellers with little of no carry-on luggage who want to get through the checkpoint quickly can elect to join a screening line marked by a black diamond sign. Less experienced “casual” travellers with multiple carry-on bags can elect to use a special screening line with a blue sign where they can take more time and avoid feeling pressurised; and families, groups and those with special needs can use a very leisurely screening line designated by a green sign.
