The hottest part of the security detectors in Beij

2022-08-23
  • Detail

Recently, some citizens in Shenzhen and Shenzhen said they were worried that the radiation of subway X-ray security detectors would cause harm to human body. More importantly, some manufacturers and users of security detectors did not have a radiation safety license

yesterday, the Beijing Municipal Environmental Protection Bureau said that the capital airport and some public places that used baggage X-ray security detectors regularly earlier had obtained the radiation safety license, and Jakob von Wolff, the global performance director of the packaging branch of kiefel Co., Ltd., which added such equipment in public places, said that the unit was also handling the radiation safety license according to the prescribed procedures

production and use should be licensed

recently, Shenzhen citizens complained that the three manufacturers of 286 subway X-ray security detectors did not have a radiation safety license issued by the environmental protection department and did not conduct an environmental impact assessment; The radiation supervision and Administration Office of Shanghai Environmental Protection Bureau also said that the use of Shanghai rail safety detectors has not obtained a radiation safety license. During the subsequent visit, it was found that there were no warning signs of radiation safety in the baggage security detector of Beijing subway

according to the measures for the administration of safety licensing of radioisotopes and radiation devices issued by the Ministry of environmental protection, units that produce, sell and use radioisotopes and radiation devices in China should obtain a radiation safety license

according to the investigation of subway baggage security detectors in the city, it is learned that their manufacturers have obtained the qualification of radiation safety license, but some users have not obtained the license at present

Beijing manufacturers are qualified

according to an unnamed person in charge of the marketing department of small luggage X-ray machine explosion detection security inspection products of Tongfang Weishi Technology Co., Ltd., its company has produced two-thirds of the luggage security detectors on the Beijing subway line and half of the luggage security detectors on the Shanghai subway line. The company has the radiation safety license issued by the environmental protection department, It has been confirmed in the radiation safety license management system of Beijing Environmental Protection Bureau

yesterday, the Beijing Municipal Environmental Protection Bureau said that the luggage X-ray security detectors used in Beijing are all products of regular manufacturers, and the manufacturers have obtained the "radiation safety license"

early users have been licensed

according to the management measures, not only the production units with good transaction conditions need to obtain environmental protection qualifications, but also the users need a license

it is understood that after the 2008 Olympic Games, Beijing began to generally use security detectors on the subway. The users are Beijing subway operation company and Beijing Hong Kong subway company respectively. However, in the radiation safety license management system of Beijing Environmental Protection Bureau, no information about the two units obtaining radiation safety licenses was found

yesterday, the Beijing metro operation company and the Beijing Hong Kong Metro Company did not respond to questions related to the radiation of Beijing Metro security detectors

■ dispel doubts

1 radiation does not harm health

guoqiuju, associate professor of Technical Physics Department, School of physics, Peking University, said that people are exposed to a certain degree of natural radiation every day, and the amount of radiation reaches 2.4msv, while mSv is the unit ratio μ Gy/h differs by three orders of magnitude, far greater than the latter. If it meets the national requirements, it is less than 5 μ Gy/h, its dose is very low

the Municipal Environmental Protection Bureau said that the radiation dose of a hospital chest X-ray examination was about 50 μ Gy, according to this calculation, it is equivalent to a medical X-ray chest X-ray if you stay for 50 hours at 5cm close to the baggage X-ray security detector. "It is safe to use the baggage X-ray security detector, which will not cause physical injury to the public passing nearby"

2 there is no need to warn if the instrument is qualified

according to national regulations, radioisotopes and ray devices should have obvious radioactive signs, but the interview found that the subway security inspection instrument did not have this sign

Tongfang Weishi responded that the principle of the security detector comes from the electronic collision, which produces X-rays after acceleration, which is different from the old hospital X-ray machine, which produces radiation through radioisotopes, and it is necessary to set warning signs for radioactive sources. It is said that the qualified security inspection equipment has a lower dose than the natural marble decorated in the office, and there is no need for warning signs

3 the license is only for enterprises

Tongfang NUCTECH responded that the radiation safety license is only issued for production enterprises, similar to the business license, not for products

Guo Qiuju said that natural radiation exists everywhere, but the degree of danger is different. The fetus of pregnant women is very sensitive and can be avoided as much as possible, but the risk is extremely small

Tongfang Weishi said that the security detector is a closed device, and there is no external radiation risk. The purpose of the security detector is to check whether the things carried are dangerous. For public places such as airports and subways, it is necessary to use the security detector for everyone's luggage

4 the radiation of the instrument is less than that of TV

the Municipal Environmental Protection Bureau said that the working principle of the subway baggage security detector is the same as that of the ordinary medical X-ray diagnostic instrument, which uses X-rays to irradiate the detected object to obtain its internal image. The maximum radiation dose of the baggage X-ray security detector used in public places at 5cm from its outer surface should be less than 5 μ Gy/h。 According to the monitoring data, the maximum radiation dose at 5cm from the outer surface of the lead curtain on both sides of the security detector channel has been less than 1 μ Gy/h。

according to Tongfang Weishi, the radiation of its security detector is far below 5 μ Gy/h, only 0.25 μ Gy/h, less radiation than the old TV. It said that the security inspection instrument produced by the company for domestic use also met foreign standards

5 how to obtain the license for the security detector

according to the measures for the administration of safety licenses for radioisotopes and radiation devices issued by the Ministry of environmental protection, the licenses of radiation work units that produce radioisotopes, sell and use class I radioactive sources, and sell and use class I radiation devices are approved and issued by the department such as the environmental director of the State Council, which displays the latest fiber material technology and products of the company. In addition, the licenses of radiation work units are issued by the provincial Approved and issued by the competent department of environmental protection of the people's Government of autonomous regions and municipalities directly under the central government

before applying for a permit, radiation work units need to organize the preparation or filling in of environmental impact assessment documents, and submit them to the competent department of environmental protection for approval in accordance with national prescribed procedures. The environmental impact assessment report must be prepared by institutions with corresponding environmental impact assessment qualifications. In addition, the unit obtaining the license should prepare an annual assessment report on the safety and protection of radioisotopes and radiation devices, and report it to the original license issuing machine 1 to have a look! Off

Tongfang Weishi said that it was issued a radiation safety license by the Municipal Environmental Protection Bureau and organized an annual report on the protection status every year. In addition, it said that radiation device units also need the inspection and certification of the CDC, that is, the radiation safety inspection report

■ voice

passengers can carry out manual inspection at their request

yesterday, a security inspector of Beijing subway said that the radiation dose of the security detector is limited, and there are lead curtains at both ends of the security detector, which are two layers thick, which can block X-rays. If the lead curtain is worn, it will be replaced at any time

"if a pregnant woman asks, we can have a manual examination." The security inspector said that many pregnant women will be more worried about the radiation of the security detector. When passing the security check, they either bypass the security detector or ask the security inspector to check manually instead of the security detector

the security inspector also mentioned that some passengers will try to be quick at security inspection and reach into the security detector to pick up their bags. Therefore, passengers should be reminded to accept the security check correctly

■ link

the X-ray security detector used in the subway is consistent with the X-ray security detector used in the airport, which uses electronic acceleration to generate x-rays in the enclosed space to penetrate the luggage. When the baggage enters, infrared induction is excited, and X-ray is generated inside. It starts from one side in a straight line and receives from the other side. Because it is not an isotope radiation source, it will not be emitted. Once there is a leak, it will also be blocked by a lead curtain

the security door that people pass through has nothing to do with X-ray radiation. It is similar to an electromagnetic field. When metal passes through, the magnetic line of force is cut and induction is generated

note: the reprinted content is indicated with the source. The reprint is for the purpose of transmitting more information, and does not mean to agree with its views or confirm the authenticity of its content

Copyright © 2011 JIN SHI