The airport scanner

El escáner del aeropuerto

Since the last failed attempt at a terrorist attack with explosive underpants, many airports have decided to further strengthen their security measures through body scanners.

These measures have ignited a heated debate about what is the limit on the violation of our privacy to guarantee security. At the same time that this debate is gaining momentum, the population's fear of the health risks that scanners at airports could have increases. Do they increase the risk of cancer in people or are they harmless?

To answer the previous question, it must be clear that, currently, two very different scanner systems are used at airports, which are the following:

  1. Millimeter wave or T-ray radiation scanner: It does not emit ionizing radiation (and therefore, neither X-rays). It uses electromagnetic waves, in a range higher than that of microwaves, to create images of the surface of the human body when seen reflected by it. Its penetrating power is low (millimeters or centimeters) which allows it to pass through clothing but does not go through human skin. Its energy emission is 10,000 times less than a mobile phone.
  2. Backscatter X-ray scanner: It uses ionizing radiation, specifically X-rays. Like the millimeter wave radiation scanner, the X-ray scanner emits low-intensity radiation that does not pass through human skin, but bounces off allowing a peek through clothing and accessories. The backscatter X-ray scanner is an older system than the millimeter wave radiation scanner.

What are the risks associated with each type of scanner?

Millimeter Wave Radiation Scanner

Because it does not emit ionizing radiation, but only electromagnetic waves in the terahertz radiation range and with little penetration, these waves are not capable of altering molecules or atoms in the human body and there is no evidence that it represents any danger to the population.

Backscatter X-ray Scanner

Although it emits X-rays (ionizing radiation capable of causing changes in molecules or atoms in the human body), they are of low energy and the emitted radiation dose is minimal. In fact, one airport scanner session is equivalent to 15 minutes of natural radiation (remember that we are constantly exposed to cosmic radiation). For the radiation dose from an airport scanner to reach the dose from a chest X-ray, a person would have to go through it 1,000 times. If we compare it with the radiation dose received in a CT scan, it would take around 100,000 times through the airport scanner to receive an equivalent dose. Thus, the increased risk of cancer from using this scanner is practically nil.

One last piece of information, did you know that the radiation dose received in a 30-hour flight is equivalent to a chest X-ray? Why are so many people obsessed with radiation from scanners and not radiation from flights (which, despite being much higher, is still safe, although frequent flyers or crews should take this factor into account?) ). In short, paradoxes of the human being and his partial perception of the world.

Practical questionnaire, if you need to travel by plane, it will be very useful

Have you ever traveled by plane? If you have not done so, you will need the help of someone who has traveled by plane.

True-False Question

1. The T-ray scanner emits ionizing radiation of the electromagnetic wave type, very similar to x-rays.

True
False

2. When we travel by plane we receive more doses of natural radiation, this is because there is a positive relationship between altitude and radiation dose.

True
False

3. One millimeter wave scanning session is equivalent to 15 minutes of natural radiation.

True
False

4. In the article they talk about the terahertz unit. This measures the frequency, and is equivalent to 10 9 Hz.

True
False

5. Going through a scanner at the airport can pose a health risk.

True
False

6. The CSN is the competent body for all issues related to nuclear safety and radiological protection in Spain.

True
False

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