New International Standard for Safety Requirements of Medical Robots for Rehabilitation Issued
Effort for developing an environment toward worldwide dissemination of advanced medical technologies
July 23, 2019
Industries in many countries have been developing medical robots for rehabilitation and people worldwide have begun using them. However, as these robots have unique mechanical features which require patients to integrally attach the robot in treatment and as the interpretation of the existing and multiple requirements for developing medical robots for rehabilitation varies depending on organization and authority, standards for examining such robots for approval are inconsistent among countries worldwide. To solve this problem, Japan filed a proposal for establishing new international standards for safety requirements of medical robots for rehabilitation with the International Electrotechnical Commission (IEC) and, based on this proposal, the IEC issued new international standard for such purpose. This issuance is expected to encourage Japan-oriented advanced medical technologies to enter global markets.
Industries in many countries have been developing medical robot equipment intended to rehabilitate patients’ movement and other functions (hereinafter referred to as “medical robots for rehabilitation”) and some such robots have already been approved by authorities and commercialized. Types of medical robots for rehabilitation include:
- Those for improving movement functions for patients who face an impairment of such functions;
- Those for assessing patients’ movement functions in a quantitative or qualitative manner;
- Those for compensating for patients’ impaired movement functions by supporting or replacing those functions; and
- Those for alleviating patients’ secondary symptoms caused by an impairment of certain functions.
As for reasons for using such robots, the following are well known:
- To reduce the burden on physical therapists and occupational therapists or address an increase in the number of patients that medical facilities can treat at the same time;
- To gain the effects of treatments which can be brought about only by using medical robots for rehabilitation;
- To formulate treatment plans with scientific grounds based on effective quantitative measuring of data and to ensure the progress in such treatments; and
- To perform assistance of and compensation for patients’ movement functions, which cannot be achieved without medical robots for rehabilitation, and thereby alleviating patients’ symptoms.
Safety requirements of medical robots for rehabilitation, which is a requirement for commercialization of such robots, are examined by respective countries under their domestic laws and regulations. In such examination, countries have been referring to the standard of IEC 60601-1 (corresponding domestic standards: JIS T 0601-1) for medical electrical equipment - general requirements for basic safety and essential performance as well as using the collateral standards of IEC 60601-1. Nevertheless, as these robots have a unique mechanical feature which requires patients to integrally attach the robot in treatment, there seems to occur a gap among countries in their interpretation of the general standards and collateral standards, and this causes inconsistency in examination standards between countries. To solve this problem, Japan considered the need of developing international standards for safety requirements of medical robots for rehabilitation.
Figure: Examples of medical robots for rehabilitation (source: IEC 80601-2-78)
2. Background to the issuance of the new standards and outline thereof
In developing standard for safety requirements of medical robots for rehabilitation, it was considered necessary to take into account both the knowledge on the safety requirements of personal care robots, in particular, physical assistant robots, and the knowledge on the safety requirements of medical equipment. Based on this awareness, seven countries, including Japan, proposed and ultimately established a joint working group of the International Organization for Standardization (ISO) and IEC, bringing together experts in the two types of knowledge.
Following this, in July 2015, the working group started a series of deliberations on new standard for safety requirements of medical robots for rehabilitation. As representatives of Japan, experts from manufacturers and other companies in the fields of service robots and medical robot equipment participated in the deliberations and coordinated new standard with experts from Canada, China, France, Germany, the ROK, the United Kingdom, the United States, Spain, Switzerland and other countries. As a result of these deliberations, the IEC decided to issue international standard therefor in August 2019. Thanks to this achievement, Japan became a Convenor of the working group. This is the first case where Japan serves as a Convenor in advancing deliberations on international standardization for service robots and medical robot equipment.
Highlights of the newly issued international standard (IEC 80601-2-78: 2019 Medical electrical equipment - Part 2-78: Particular requirements for basic safety and essential performance of medical robots for rehabilitation, assessment, compensation or alleviation) are as follows:
- Introduction of the idea of actuated applied parts, which makes the standards applicable to any medical robots for rehabilitation beyond the forms thereof, e.g., exoskeleton-wearable type, robot arm type and cane type.
- Addition of safety requirements in light of ISO 13482 for safety requirements for personal care robots and JIS B 8446-2 for safety requirements for low power restraint-type physical assistant robots.
- Subdividing the standards for “unintended movement” under Item 18.104.22.168 of the general standards into more specific ones;
- Clarifying safety requirements for unintended movement derived from shared control between a patient and a robot (and an operator);
- Providing new requirements for preset values of output limits to address the difference in patients involving risks of injuries caused by passive movements or external force;
- Improving the concreteness of the safety requirements for “release of patient”;
- Adopting the idea of “protective stop”; and
- Adopting risk management for preventing mis-alignment of an actuated applied part of a robot and a patient.
- Clarification of the standards for methods of estimating the total load of the respective parts of a robot and those for determining whether or not the respective parts of a robot fall into the category of support systems under Item 9.8 of the general standards, both of which take into consideration the dynamic interaction between an actuated applied part of a robot and a patient;
- Creation of a new classification of “walking” under the category of robots moving on a floor to which part of the robot repetitively touches so as to provide new safety requirements unique to walking-type robots.
- Adoption of risk management for preventing “loss of situation awareness” for the purpose of permitting the use of robots in the following situations:
- Where no operator exists next to the target patient and robot; and
- Where the target patient becomes the operator for him/herself for certain operations.
3. Expected effects
The EU, the United States and many other countries and regions have shown their intention to introduce the standard into their domestic standard. This introduction is expected to facilitate smooth assessment and approval, in other countries, of medical equipment derived from Japan-oriented innovative technologies. Japan expects that Japanese medical equipment industries will design and produce medical equipment in compliance with the standards and disseminate their made-in-Japan, safe and secure medical equipment to medical sites worldwide and that these efforts will contribute to enhancing such industries’ competitiveness in global markets.
To encourage Japanese industries in the field to smoothly provide Japan-oriented advanced medical technologies to the rest of the world, METI will strive to assist rule-making activities, including international standards. In addition to the standard for safety requirements of medical robots for rehabilitation, on the same date, the IEC also issued international standard IEC80601-2-77 for safety performance of surgical robots.
- New International Standards for Safety Requirements of Surgical Robots Issued (METI press release on July 16, 2019)
Note: This successful international standardization is partly due to the achievements under the project titled “Project for Accelerating Strategic Development of International Standards: Activities for Development of International Standards in the Fields involving Governmental Strategies (international standardization for safety requirements by type of service robots).”
Division in Charge
International Standardization Division, Industrial Science and Technology Policy and Environment Bureau