In health care, different artificial radiations are used in different fields for diagnostic and therapeutic purposes. In addition to the intended effects, their use can pose hazards to both patients and employees in various ways. This applies in particular to so-called ionizing radiation. This is when radiation is so energetic that it splits (ionizes) atoms or molecules as it passes through matter. Widely used in medical technology, especially X-rays and gamma radiation, a certain radioactive radiation. In order to keep the associated risks as low as possible, certain organizational, technical and personal protective measures are required, which can be summarized under the term radiation protection organization.
Using ionizing radiation
1.1. X-ray procedure
Classic X-ray and computed tomography (CT) examinations are diagnostic imaging procedures using X-rays. In most of these examinations, employees leave the so-called control area, where a certain intensity of X-ray radiation occurs during the exposure, and control the procedures from an operating room that is shielded against radiation. Even when using mobile X-ray equipment (z. B. in the case of non-transportable patients in the intensive care area) the device-specific defined controlled area must be left as far as possible for the moment of admission of employees.
However, there are quite a few situations in everyday medical life where employees are exposed to X-rays, z. B.:
- in case of assistance at the patient resp. Patients during the examination (support, hold, reassure)
- in a variety of invasive examinations and treatments performed on patients under X-ray control (div. cardiological and other endoscopic examinations and procedures, surgical procedures under X-ray control)
Here, medical personnel work directly at or in the radiation field. Even though the radiation doses used have become smaller and smaller in the course of technical development and modern devices can apply radiation more specifically and avoid scattered radiation, the high number of examinations and interventions performed means that the continuous or. keep the total exposure as low as possible.
In addition to the radiology departments, which mainly perform diagnostic imaging procedures u. a. with X-rays, this is typically also used in cardiology, urology, surgery as well as in operating theaters.
1.2. Nuclear Medicine
In nuclear medicine, mainly diagnostic, sometimes also therapeutic procedures are carried out with so-called open radionuclides. These are radioactive substances that are prepared and introduced into the body as medicines (radiopharmaceuticals). Their radiation can be precisely measured externally with appropriate equipment, allowing an imaging procedure to be used to examine body tissues, especially the metabolic processes that take place there (z. B. organ functions). Frequently used diagnostic procedures are scintigraphy, positron emission tomography (PET) and SPECT. In a similar way, therapeutic effects can also be achieved on certain target tissues (e.g., in the body). B. Radioiodine therapy for thyroid disease). Risks arise in nuclear medicine from handling the radiation sources with which pharmaceutically prepared radiopharmaceuticals are usually "charged" shortly before administration (often gamma emitters), as well as during transport and administration of the radiopharmaceuticals, z. B. in so-called therapy wards, where patients have to stay for a few days after administration until the administered radiation has subsided.
1.3. Radiation therapy
This refers to therapeutic procedures with different ionizing radiation (often so-called gamma radiation or electron radiation, rarely also other particle radiation). These radiations are either applied to the body from the outside (teletherapy) or encapsulated radiators are specifically inserted into the body at the sites where radiation treatment is to take place (brachytherapy). These procedures also fall under the Radiation Protection Ordinance.
Use of non-ionizing radiation in hospitals
Other artificially created radiations are also used in healthcare, z. B. electromagnetic radiation, laser radiation, UV and infrared radiation, micro and ultrasonic waves. In many cases, due to their effectiveness, these radiations can also cause side effects on the patient or. on the patient and injury or health risks for employees lead. Therefore, the application must always be recorded in a risk assessment and measures must be defined that make safe working possible. In addition, two common, non-ionizing radiation-based procedures have a specific legal framework that must be considered in a hospital’s safety organization, even though these topics are not classically understood under "radiation protection".
2.0 Occupationally exposed persons
Basically, all employees who are employed in the controlled area of an X-ray or CT system must be considered from a radiation protection point of view, e.g. B. in radiology, on mobile X-ray equipment, during endoscopic or surgical procedures under fluoroscopy (cardiology, endoscopy, surgical area, urology). No special radiation protection measures are required for employees who work in the above (or comparable) departments but are never in the examination or procedure rooms or in the controlled area of a mobile unit (usually within a 3 m radius) while X-rays are being used.
For all employees working in the controlled area, the following must be observed
- a suitable person-related measurement of the radiation doses must be carried out
- the necessary protective measures (technical, organizational, personal) are defined
- be assigned to predefined categories depending on the radiation exposure to be expected. This determines whether an annual medical examination is required.
The person responsible for radiation protection is responsible for this; implementation is carried out in each case by the radiation protection officers of the individual areas.
2.1. Magnetic resonance imaging (MRI)
Strong electromagnetic radiation is used for this imaging diagnostic procedure, which is produced in the MRI machine using electrical energy and helium as a coolant. There are specific risks associated with this, especially due to the strong attraction of magnetic metal parts, which must not be allowed to come into the vicinity of the MRI device, and due to the use of helium, which must be drained quickly in an emergency in the event of malfunctions without endangering patients or employees. From a radiation protection point of view, however, MRI procedures are less critical than z. B. X-ray-based procedures, because although strong magnetic fields can certainly have certain physiological effects, no harmful effects of magnetic fields on humans have been established to date. With regard to all occurring hazards, certain working conditions must be observed, which are summarized in the Ordinance on the Protection of Employees against Hazards from Electromagnetic Fields (Arbeitsschutzverordnung zu elektromagnetischen Feldern – EMFV).
2.2. Laser procedure
Laser radiation is a high-energy optical radiation. It is used in a variety of ways in health care, especially for the ablation, deposition and vaporization of body tissue in the course of surgical procedures. The penetration depth of laser radiation into matter is rather low, so that work can only be carried out on the surface of the body. Accordingly, risks from laser radiation are primarily for the skin and eyes, but with high-energy devices there may also be deeper tissue destruction. Laser equipment is classified into laser classes from 1 to 4 according to DIN EN 60 825-1 "Safety of laser equipment; Part 1: Classification of equipment, requirements and user guidelines" depending on the intensity and the associated risks. Medical devices are generally subject to classes 3 and 4, with which certain protective measures are associated. In addition to basic requirements such as safe equipment design, protection from scattered radiation to the greatest possible extent, etc. these are, above all, the use of laser protection officers and specific precautionary measures. The legal basis for this is the Occupational Health and Safety Ordinance on Artificial Optical Radiation (OstrV) and the associated Technical Regulation on Optical Radiation (TROS) Laser Radiation.
radiation protection organization in the hospital
The risks associated with the use of ionizing radiation are generally considered to be relatively high. Although the risk of acute radiation damage to employees during handling of ionizing radiation is low, it is not possible to prevent it. However, even very low levels of exposure that occur repeatedly over many years can cause long-term damage, especially with regard to radiation-induced cancers. As soon as procedures are used that fall under the Radiation Protection Ordinance or the X-ray Ordinance, certain specifications must therefore be observed, which u. a. controlled by the state occupational health and safety inspectorate.
3.1. radiation protection supervisor and radiation protection officer
According to the Radiation Protection Act § 69, the employer or. the employer himself or. a person authorized to represent the company as radiation protection supervisor or radiation protection officer. Radiation protection officer to be appointed. In the hospital, this is usually the or. a managing director. She resp. it thus bears the overall responsibility for the use of ionizing radiation and the associated protective measures. Among other things, it must or. he or she shall appoint radiation protection officers in all relevant areas who are responsible for "managing or supervising a [radiation protection-relevant] activity" "to the extent necessary to ensure radiation protection in that activity." In the hospital, these must be physicians or. Act doctors who are able to bear the professional responsibility for the procedures on site. For this purpose, they must acquire and regularly refresh the relevant technical knowledge. Care must be taken to ensure that, even in the event of personnel changes in the medical service and in addition to the many other medical tasks, the function of the or. of the radiation protection officer is manned and active in the relevant areas. As a rule, they are u. a. responsible for the radiation protection instruction and the radiation protection instruction (s. u.), but also for all other practical radiation protection measures.
The person responsible for radiation protection and the radiation protection officer must cooperate with the works council or the staff council and the specialists for occupational safety in the performance of their duties.
3.2. Radiation protection instruction
According to § 45 StrlSchV, this must be the responsibility of the or. 5 The results must be archived and submitted at least annually to the responsible company physician or radiation protection officer, but for conventional X-ray systems only on the instructions of the authorities . It contains all regulations on radiation protection, operating procedures, dosimetry, operating documentation, plant inspection and maintenance, accidents and malfunctions.
3.3. Radiation protection training
Because of the comparatively high risks, also and especially in the long-term handling of ionizing radiation, radiation protection-related instruction must be documented and carried out at least once a year (§ 63 StrlSchV).
3.3.2 Medical surveillance
Employees who are assigned to category A must be examined by a physician authorized in accordance with the Radiation Protection Ordinance before starting work and once a year thereafter. be examined by an authorized physician, certifying that there is nothing to prevent continued employment under occupational exposure (§ 77 StrlSchV). The examining physician must be provided with. the dosimeter evaluations are available to the examining physician.
According to § 35 64 StrlSchVRoV, the absorbed radiation dose (body dose) must be measured and documented on all "persons who are in a radiation protection area [here this corresponds to the controlled area]for reasons other than for their medical or dental examination or treatment". Therefore, it must be ensured that all employees working in the controlled area wear dosimeters (usually on the front of the body under the X-ray protective clothing, for certain procedures also as ring dosimeters on the finger of one hand). These are sent regularly (usually monthly) to approved monitoring sites for evaluation. This is to check that certain body part-related annual doses and a maximum lifetime dose are not exceeded. Significant exceedances of the permitted radiation doses are very rare in the practice of normal hospital operation. The results must be archived and reported at least once a year to the responsible company physician or radiation protection officer. be made available to the responsible company physician so that the results can be taken into account in the radiation protection examination. Occupationally exposed persons are listed under a personal identification number in the Radiation Protection Register, which exists at the Federal Office for Radiation Protection BfS. If employees are occupationally exposed to radiation for the first time at the hospital, the hospital is responsible for registering them there.
3.5. Occupational health precautions
According to § 77 StrlSchV, an occupationally exposed person who is regularly in the controlled area of an X-ray facility near the radiation aisle during fluoroscopy (category A according to § 71 StrlSchV) may only perform tasks there if, within one year prior to the start of the performance of the task, he or she has been instructed by an authorized physician or. has been examined by a physician authorized to do so and the person responsible for radiation protection has a certificate issued by this medical specialist stating that there are no health concerns for the performance of the task. This examination must be repeated annually. Category A includes z.B. medical and assistant staff regularly employed directly on patients in interventional radiology, surgery or cardiology examinations or treatments under fluoroscopy. The radiation protection supervisor must ensure, via the responsible radiation protection officers, that there is always an up-to-date overview of the employees to whom this applies.
3.6. Plant safety
From a medical technology perspective, there are a number of regulations that must be complied with in the planning, construction and operation of radiation protection-relevant facilities and equipment. This relates to the condition of the space (z.B. shielded operating rooms of X-ray equipment), safe supply of energy and operating materials as well as safe control, furthermore extensive reporting, documentation and regular testing requirements. These are usually carried out by the medical technology department of a hospital or. coordinated.
3.7. Technical protective equipment
In the case of devices used in the controlled area or. If the patient is working under fluoroscopy, the construction and design have a great deal to do with whether, where and how much radiation has an effect on patients and employees outside of the intended useful effect. Radiation doses, the controllability of the intended effect and the quality of the shielding are constantly being optimized. However, the service life of complex medical technology devices is often long due to the very high investment sums involved. Therefore, it cannot be assumed that an operated device always has the current best possible level of system safety.
In some circumstances, occupational safety-related retrofits to equipment may be considered, such as. B. improved shielding for areas where employees are regularly exposed to stray radiation during procedures under fluoroscopy.
In addition, there are mobile shields such as lead glass panels and curtains that can be used to minimize radiation exposure for employees.
3.8. Personal protective equipment
The use of X-ray protective clothing, which is also used in the field of nuclear medicine and radiation therapy, is common and unavoidable. Depending on the type and dose of radiation, lead aprons are worn, and in addition, depending on the procedure, thyroid protection or. Protective gloves and X-ray goggles or visors. This protective equipment is unavoidable, but its weight and wearing characteristics make a not inconsiderable contribution to the strain on employees. The wearing of radiation protective clothing must therefore always be taken into account in the risk assessment.