Reformation of the Japanese Guidelines for Cellular Phone Use in Hospitals Eisuke Hanada
Takashi Kano
Graduate School of Science and Engineering Saga University Saga, Japan
[email protected]
Faculty of Health and Medical Care Saitama Medical University Hidaka, Japan
[email protected]
Abstract— The Electromagnetic Compatibility Conference Japan announced in August, 2014 its reforms to the 1997 "Guidelines for use of mobile phones and other devices in hospitals." The guidelines were amended because the medical electromagnetic environment has changed dramatically with the termination of second-generation cell phone service and the spread of wireless LAN, etc. Programs for the improvement of patient service and the operating efficiency of hospitals through the use of wireless communications have become the norm. Compared with the former guidelines, the hospital areas in which mobile phones can be used have been extended, with the condition that at least 1m be kept from a medical device. Also, the guidelines newly require the appropriate management of wireless communications and the electromagnetic environment. Our specialized research has led to these amendments. Here we explain the content and basis of the new guidelines. Keywords— Mobile phone, Electromagnetic interference, Wireless communication, Electromagnetic environment
I. INTRODUCTION The original Japanese guidelines for mobile phone use in hospitals were enacted in 1997 [1]. The Electromagnetic Compatibility Conference Japan (hereafter, EMCC) promulgated the old guidelines, according to which many hospitals and clinics have severely restricted the use of mobile phones. However, with advancements of cell phone technology and service and the spread of public wireless LAN, the electromagnetic environment of hospitals has greatly changed. Mobile and smart phone use has spread explosively in Japan. Therefore, permission for the expanded use of wireless communications in hospitals is expected to enable the improvement of patient service and to greatly improve the operating efficiency of the hospital and its staff. In response to the changing environment, updated guidelines were formally announced on August 19, 2014. Amendment of the guidelines was done by an expert committee formed by EMCC. The expert committee consisted of members selected from academic experts; staff from the Ministry of Internal Affairs and Communications; the Ministry of Health, Labor and Welfare; a cellular phone business operator; a medical device manufacturer; and a hospital
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administrator. The authors of this paper are the chairman and sub-chairman of the expert committee. Compared with the situation under the old guidelines, the new guidelines enable hospitals to expand the areas in which mobile phones can be used, on the condition that a safe distance to be kept between cell phone handsets and medical devices. The new guidelines also require hospitals to appropriately manage their wireless communication systems and electromagnetic environment. In this paper, we show the content and basis of the new guidelines. II. THE BASIS OF THE OLD GUIDELINES A report that was released along with the old guidelines presented the results of irradiation experiments on the effect of electromagnetic waves on medical devices. The irradiation sources were a “shoulder phone” (using the 800 MHz band), an analog cellular phone (800 MHz band), a digital cellular phone (800 MHz and 1.5 GHz bands), and a Personal Handyphone System (PHS, 1.9 GHz band). About 360 models of 78 kinds of devices were subject to irradiation. These included medical devices such as pumps, respirators, electric knives, and X-ray CT scanners. The procedure of the irradiation experiment was as follows. The object subject to testing, in the operating state, was placed in an anechoic chamber. The researcher brings a radiation source ever closer to the test object, stopping at the point at which it malfunctions, then records the distance and type of malfunction. Cellphone handsets and half wavelength dipole antennas were used as radiation sources. The report also included the results of an irradiation experiment for 228 models of cardiac pacemakers. Irradiation experiments were done on some medical devices using the electromagnetic wave of the ham radio frequency band, and the results were also included in the report. Based on these results, the fundamental posture of the old guidelines was to forbid all use of the mobile phones in hospitals, except in "areas specially permitted by the hospital, such as in waiting rooms." Also, the use of transceivers in hospitals, other than those of a specified low power, was forbidden, except for in emergencies or at the time of a disaster. Because the maximum output of a PHS was as weak as 0.08 W, their use was allowed in special zones managed so that a
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distance of several centimeters was kept between them and other devices [3]. The old guidelines stated that a carried-in PHS terminal should be treated in the same way as a mobile phone, not allowed in designated areas, because they are so alike in appearance. The old guidelines also required that a cell phone terminal should be 22 cm or more from a cardiac pacemaker. III. PRESENT ELECTROMAGNETIC ENVIRONMENT OF JAPANESE HOSPITALS
In 1997, when the old guidelines were promulgated, the available public mobile communication systems technologies included car telephones, shoulder phones, analog cellular phones, and the second-generation (PDC) digital mobile phone. The first three were terminated by 2012, so they are no longer problematic. PHS is still in use. The generation classification of Japanese mobile phones is shown in Table 1. At present, the Japanese standard for cell phone service is shifting from the third generation to LTE. TABLE I. GENERATION CLASSIFICATION OF PUBLIC MOBILE PHONE SERVICES IN JAPAN Generation First generation Second Generation Third Generation Fourth Generation
Status of Service Terminated Terminated In service In service
Main Standards Analog PDC, CDMA-1 CDMA2000, W-CDMA LTE, WiMAX
The maximum outputs from mobile phone terminals in Japan were 2W for a car telephone or a shoulder phone and 0.8W for a second-generation mobile phone (PDC). The maximum output of a third generation mobile phone terminal has decreased to 0.25W. From a wireless LAN apparatus it is about 0.2W, and the output of a PHS terminal is the same as before, as weak as 0.08W. In addition, it is important to note that the output of base stations has not changed. Currently, the base station of a mobile phone has a maximum output of 10-20W. As mentioned above, the maximum output from terminals such as mobile phones and smart phones that are likely to be used in a hospital has become lower than before, which was a major factor leading to the amendment of the guidelines. At present, a large number of Japanese children have mobile or smart phones. Mobile phone use is now around 90% compared with about 30% in 1997. Mobile phones can be used anytime, anywhere. This has created problems related to the manners of users, which must be taken into consideration as a factor that can interfere with the functioning of a hospital. Furthermore, although the protection of the private information of patients and the hospital staff has improved, improvements in technology, such as photography and video recording capability on mobile phones, make it imperative that constant awareness be given to protecting personal information from new threats. IV. CONTENTS OF THE NEW GUIDELINES
The frequency bands of the electromagnetic waves used by mobile phones include the traditional 800 MHz and 1.5 GHz bands, with the 1.7 GHz and 2.0 GHz bands now coming into use. Communication using wireless LAN has been standardized, and it is being used not only as a data communication medium but also for voice communication. In addition, new communication standards for electromagnetic wave radiation, such as for Radio Frequency Identification (RFID), ZigBee, and Ultra Wide Band (UWB) communication have been enacted and systems using these new technologies have been developed. These will be useful in the materials management systems and sensor networks of hospitals. As stated in a report concerning the old guidelines, almost all electromagnetic interference (EMI) with medical devices caused by mobile phone use is from the electromagnetic field emitted by phone terminals. From the viewpoint of the frequency band used in mobile communication systems, magnetic field components can be ignored as a causal factor. Although the magnetic field is of concern when using RFID, the maximum output allowed in the RFID standards is only 13.56 MHz, which means there is no possibility of electromagnetic interference by a RFID instrument, unless the instrument is used at an extremely short distance from a medical device. While electric field intensity is in inverse proportion to the distance from the emission source, it is proportional to the square root of the antenna output. Advancements in mobile phone technology have decreased the output from the terminal.
A. Rules for mobile phone use in designated areas The new "Guidelines for Use of Mobile Phones and Other Devices in Hospitals – For Secure, Safe Use of Wireless Communication Devices in Hospitals –" [2] in principle permit mobile phone use, with two assumptions: The observance of good manners and the maintenance of a fixed distance from medical devices. The main content is summarized in Table 2. A report about the new guidelines (hereafter, new report) [5] describes the conditions for use of terminals in wards and consultation rooms, Table 2 and as follows. There is comparatively little potential for interference by cell phone use with the types of medical devices usually used in wards; therefore, their use in wards is now allowed. However, the cell phone terminal must be kept outside the “designated distance” from any medical devices for which the possibility of EMI has been demonstrated. This is fairly simple in single patient rooms, but is more complicated in the case of multi-patient rooms, in which it may be desirable to make restrictions to avoid EMI and/or to promote good manners. From a privacy standpoint, because telephone calls and the use of E-mail and the WEB create noise that can disturb other patients, it may be necessary to set up restrictions to or forbid the use of certain functions, especially at night. The guidelines for the use of medical devices in general wards can be summarized as follows; From the viewpoint of EMI prevention, if separation can be maintained cell phones can be used safely, and the only restrictions should be made from the viewpoint of manners.
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TABLE II. REFERENCE CASES: ESTABLISHMENT OF RULES FOR USING MOBILE HANDSETS BY AREA [2] Areas
Calls
E-mail, Web, and Other Applications
(1) Cafeterias, waiting rooms, corridors, elevator halls, etc.
Allowed
Allowed
(2) Patient rooms, etc.
Partially allowed*
Area-specific Precautions Mobile handsets in use should be separated by at least the specified separation from medical electrical equipment. Use should be restricted as necessary if mobile handsets in use are in the vicinity of the restricted areas. Texting while walking is dangerous and should be avoided.
Allowed
Mobile handsets in use should be separated by at least the specified separation from medical electrical equipment. In a patient room for multiple patients, certain consideration is necessary from a perspective of public manners, such as placing restrictions on Calls.
(3) Consultation rooms
Not allowed
Partly allowed (No need to switch off)
(4) Operation rooms, ICUs, laboratories, treatment rooms, etc.
Not allowed
Not allowed
(5) Space for mobile phones, etc.
Allowed
Allowed
There is no need to turn off mobile handsets (provided that mobile-phone users keep distance from medical electrical equipment for at least the specified separation.) Consideration is necessary. For example, use should be avoided to prevent the disturbance to medical examination or other patients. Mobile handsets should not be used and should be turned off. (Or they should be switched to the mode that does not emit radio waves.
*Which matters should require attention from the perspective of public manners cannot be decided in a single, uniform way. Note that the above cases are for reference only; specific rules are left to the discretion of individual hospitals.
A description of cell phone restriction in consultation rooms is as follows. It is desirable to refraining from cell phone use to insure that they not hinder medical examinations or interfere with other patients. Also, many medical devices used in this area are used for diagnosis, and any extraneous noise can interfere with and affect the quality of the diagnosis, which in turn can reduce the effectiveness of treatment. Moreover, although use may be restricted, the power of cell phones does not need to be turned off. Although comparatively many medical devices used in consultation rooms have electromagnetic immunity, it is thought that simple solutions to problems are possible even if interference occurs. Therefore, when separation can be maintained, there is no reason to require people to turn off the power on their devices and telephone calls should only be restricted from the viewpoint of manners. B. Designated distance The 1 m "designated distance" in the guidelines, as indicated in Table 2, is the minimum safe distance that must be kept between a mobile phone terminal and a medical device. In the report, the distance is written as a “recommended separation distance.” The reasons behind this are as follows. The standard for the recommended separation distance in the guidelines is based on the Electromagnetic Compatibility standard for medical devices (JIS T 0601-1-2:2012) and the results of experimental investigations. With the current mobile phone systems, when the 250 mW maximum output power is applied at the recommended separation distance formulated in the standards, the recommended separation distance would be 1.15 m (the relative gain was 0 dB). However, the
recommended separation distance in the standards was set at 1 m for the following reasons. 1) Because the relative gain is about -2dB for most cell phone terminals, the recommended separation distance will be set at 0.92 m. 2) In our experimental investigation, the maximum distance at which "a phenomenon that affects medical treatment" was observed was 18 cm. (This investigation was a limited, not comprehensive, experimental investigation into medical devices for which we were anxious about influence. Also, "a phenomenon that affects medical treatment" does not include phenomen such as confusion caused by allophones or the bluring of labeling. 3) "The recommended separation distance" should be easy for a user to understand 4) In addition, the immunity of older medical devices in hospitals needs to be confirmed because there may be products that follow JIS T 0601-1-2:2002 (1st edition, old edition) or a product from before JIS came into existance. In JIS T 0601-1-2:2002, no evaluation has been done of all the frequencies currently used by mobile phones.” JIS T 0601-1-2:2002 is almost the same as IEC60601-1-2 Ed.1, and JIS T 0601-1-2:2012 is almost the same as IEC60601-1-2 Ed.2. The recommended separation distance is computed using the theoretical calculated value and a value that combines the relative gain of an antenna that is used by a terminal. The previously quoted standards require that the normal operation of general medical devices be maintained in an electromagnetic field of 3 V/m and that normal operation of a life support system be maintained in an electromagnetic field
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of 10 V/m. In order to use a medical device in Japan, the Pharmaceutical Affairs Law must be followed. In an environment in which 1 m of separation can be maintained, almost all medical devices will operate normally. C. Use of mobile communications equipment in hospitals, other than mobile phones The new guidelines concerning mobile communications equipment other than mobile phones refer to such instruments as PHS, wireless LAN, and RFID. The output of these instruments is weaker or the same as that of a standard cell phone terminal, except for some high output type RFID tag readers. The new guidelines basically permit the use of these instruments. However, they recommend that some situations be avoided. One is when a radiation source is placed so close to a medical device that the device will be in the near field of the radiated electromagnetic field. Another situation is when the radiation source touches a medical device. Specifically, "it is forbidden to place a radiation source on a medical device." Also, the new guidelines caution against new smart phone models that have both a wireless LAN function and a cellular telephone function. D. Construction of an Electromagnetic Environment Management System The new guidelines comment on "the substantial electromagnetic environment management system of the hospital," an item that is not in the old guidelines. Since the introduction of wireless communications, advances in Information and Communication Technology (ICT) have been remarkable in Japanese hospitals. It is recommended that an administrator ("EMC administrator") be assigned in the hospital to support efforts to keep the electromagnetic environment safe. The guidelines list the possible duties of an EMC administrator, as follows 1) EMC evaluation of wireless communication instruments and the medical devices that are used in hospitals. 2) Evaluation and the improvement of the radio wave environment of hospitals 3) Formulation of rules about mobile phone use, for patients, guests, and staff members 4) Organization and construction of a system for the supply, introduction, employment, and management of medical devices and the instruments for wireless communication in order to build a safe EMC environment 5) Promote public awareness activities for hospital users and develop education programs for the staff 6) Continuous collection of the latest technical information E. Other recommendations in the new guidelines In addition to the above, the new guidelines recommend that medical device producers and suppliers develop devices with higher immunity, to investigate the cause of problems in cooperation with the hospital staff when a problem occurs, and to disclose all of the information they have pertaining to EMC. Similarly, the guidelines request cellular phone business operators to make their specifications and warrantees
transparent and available to users, while asking for cooperation and the provision of information that would be useful in the investigation of problems that might occur. F. New guidelines and the electromagnetic environment of a hospital In Japan, there are strict regulations for the use of electromagnetic waves, as in the U.S. and Europe. Only use of mobile phones that follow the standards of the third generation or later, shown in Table 1, is permitted in Japan. If a wireless LAN apparatus does not meet the standards set by Japanese law, its use is prohibited. The output of each instrument is regulated by the Japanese radio law. Thus, if someone brings a mobile phone to Japan from another country, it can only be used if it follows the Japanese standards. The new guidelines have been created based on this premise, which is one of the factors that enabled expansion of the range allowed for the use of mobile phones. Fears of EMI with medical devices by the waves generated by mobile phones have decreased because of the termination of older types, second generation or earlier, of mobile phone services. In the near future, it will be more important to concentrate on electromagnetic fields that leak from instruments used in daily life and electromagnetic noise radiation from medical devices. These include things like microwave therapy equipment [6] and instruments such as microwave ovens and personal computers that could be electromagnetic field emission sources when used in a hospital [7]. The output of these instruments can be much stronger than that from communication apparatus. Few investigations of such technologies have been done to present. With the increased spread of radio wave use, we think that investigation of electromagnetic fields that invade from outside hospitals is important [8], along with the investigation of electromagnetic noise, as mentioned above. Solutions to maintaining a safe environment for medical devices include electromagnetic shielding of the device and keeping a set distance between a device and a radiation source, based on the results of investigation. V. PUBLIC COMMENTS AND OUR REPLIES The final draft of the new guidelines was made in June 2014. Public comment to the final draft was invited through the Ministry of Internal Affairs and Communications [9]. In response, 14 comments were made. One comment was to caution against the misuse of the marking of products to verify that they conform to the technical requirements. This was added to the final draft. About half of the comments supported maintaining the old guidelines or to more severely restrict the use of mobile phones, mainly due to anxiety about the influence of electromagnetic fields on the human body. Our response to these comments was that "the influence on the human body is outside the subject of these guidelines." This was done to avoid conflict with the "Guidelines for Radio Wave Exposure on the Human Body," which are responsible for this topic [1]. Our new guidelines are limited to concerns about electromagnetic influence on medical devices.
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VI. POSSIBILITIES CREATED BY AMENDMENT OF THE GUIDELINES
Amendment of the guidelines does not mean absolute permission is given for mobile phone or wireless LAN use in hospitals. The main purpose of the old guidelines was to prevent EMI with medical devices resulting from the electromagnetic field induced by cell phones. In contrast, the new guidelines support the management of the electromagnetic environment by presenting new and updated viewpoints on matters such as manners, patient safety, and personal data protection, while at the same time somewhat loosening the former regulations designed for EMI prevention. Proper management of the electromagnetic environment is important to the smooth functioning of the modern medical service industry. We feel that the new guidelines will contribute to the smooth, safe introduction of new technologies such as the portable radiographic apparatus that has been recently introduced, and that they will contribute to improved management of the patient monitoring and treatment systems that are already in use. A report released at the same time as the new guidelines illustrates three examples of advanced technological integration in Japan (Shimane University Hospital, Fukui University Hospital, and Allied Telesis, Inc.). All realized the safe integration of the electromagnetic environment and wireless communications through the great efforts of talented, forward thinking staff members hired by these universities. Shimane University Hospital is an example of the successful ICT-ization of a previously somewhat randomly implemented environment. This was done as follows.
Introduction of an example of the data communications infrastructure using the IEEE802.11 series and an electromagnetic field propagation simulation Enabling an ubiquitous environment through integration of the hospital information systems Introduction of portable radiographic apparatus with a wireless communication function Introduction of a management system that uses RFID tags attached to surgical implements Development of an active RFID tag system for the management of medical devices Fukui University Hospital is an example of what the future holds. In their system, virtualization (virtualization of clients and virtualization of servers) of the hospital information system includes the introduction of the smart phone as a hospital information system terminal. The system also includes sensor networks constructed using ZigBee and Bluetooth. The Allied Telesis, Inc. case illustrates the wireless communications technology now available to hospitals. It reports on wireless LAN technology that covers all of the domains with a single channel. It also shows a nurse call system that uses IP communication.
11]. Similar technologies will be introduced in Japan in the near future. To insure that communication is possible at the required speed and range, it will be necessary to take steps to minimize noise and interference while at the same time maintaining security. VII. . CONCLUSION Revised Japanese guidelines for EMI were recently announced. Although they have received some mention in newspapers and on television, continuing public awareness activities are important. The new guidelines allow each hospital to determine their own rules in accordance their specific conditions, as in the notes to Table 2. This is because the kinds of medical devices used, their number, and the needs of their patients differ based on their clinical specialties, equipment, and the functions required by each hospital. While some hospitals permit the extensive use of mobile phones, others do not in most areas of the hospital. Because of the complexity, the construction of an EMC department and the training of an EMC administrator will be important to creating a safe, efficient hospital environment. We think that the introduction of ICT to hospitals will continue to increase tremendously. We also think that these amendments to the guidelines should not be thought of as final, but that they should be constantly updated when necessary in order to promote the safe, timely introduction of new technologies as they emerge. ACKNOWLEDGMENT The authors wish to deeply thank to the other members of the expert committee and the Electromagnetic Compatibility Conference Japan. This work is partly supported by JSPS KAKENHI, Grant-in-Aid for Scientific Research (B) No.15H04794). REFERENCES [1]
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