1.1 本试验方法包括测量医疗器械上静态磁场梯度（空间磁场梯度）产生的磁感应位移力，并将该力与医疗器械重量进行比较。 1.2 本试验方法不解决其他可能的安全问题，包括但不限于:磁感应扭矩、射频（RF）加热、感应加热、噪声、设备之间的相互作用以及设备和磁共振（MR）系统的功能性问题。 1.3 本测试方法适用于可从字符串挂起的设备。本测试方法不包括不能从字符串挂起的设备。试验期间，悬挂装置的绳子的重量必须小于1 % 测试设备的重量。 1.4 本试验方法应在水平钻孔MR系统中进行，静态磁场水平定向并平行于MR系统孔。 1.5 以国际单位制表示的数值应视为标准值。 本标准不包括其他计量单位。 1.6 本标准并非旨在解决与其使用相关的所有安全问题（如有）。本标准的用户有责任在使用前制定适当的安全、健康和环境实践，并确定监管限制的适用性。 1.7 本国际标准是根据世界贸易组织技术性贸易壁垒（TBT）委员会发布的《关于制定国际标准、指南和建议的原则的决定》中确立的国际公认标准化原则制定的。 ====意义和用途====== 5.1 本试验方法是确定医疗器械的存在是否可能在磁共振检查期间或磁共振环境中对个人造成伤害所需的方法之一。应解决的其他安全问题包括但不限于:磁感应扭矩（见试验方法 F2213页 )和射频（RF）加热（见试验方法 F2182页 ). 实践中的术语和图标 F2503 应用于标记设备在磁共振环境中的安全性。 5.2 如果指定磁场条件下的最大磁感应位移力（参见 附录X3 )小于由于重力（其重量）作用在设备上的力，假设应用磁感应力施加的任何风险不大于地球引力场中正常日常活动施加的任何风险。本声明不构成验收标准；它是作为保守的参考点提供的。可能可以接受更大的磁感应位移力，并且在特定情况下不会伤害患者或其他个人。 注2: 例如，对于正在或可能受到大于重力力的磁位移力的植入装置，可以考虑植入物的位置、周围组织的性质和体内固定方式。对于磁感应力大于重力的非植入设备，应考虑减轻抛射物风险，这可能包括固定或栓系设备，或将其从磁共振环境中排除，使其不会成为抛射物。 5.3 最大静态磁场强度和空间磁场梯度随磁流变系统的不同而变化。 附录X3 为计算允许的静态磁场强度和空间磁场梯度提供指导。 5.4 仅此测试方法不足以确定设备在MR环境中是否安全。

1.1 This test method covers the measurement of the magnetically induced displacement force produced by static magnetic field gradients (spatial field gradient) on medical devices and the comparison of that force to the weight of the medical device. 1.2 This test method does not address other possible safety issues which include, but are not limited to: issues of magnetically induced torque, radiofrequency (RF) heating, induced heating, acoustic noise, interaction among devices, and the functionality of the device and the magnetic resonance (MR) system. 1.3 This test method is intended for devices that can be suspended from a string. Devices which cannot be suspended from a string are not covered by this test method. The weight of the string from which the device is suspended during the test must be less than 1 % of the weight of the tested device. 1.4 This test method shall be carried out in a horizontal bore MR system with a static magnetic field oriented horizontally and parallel to the MR system bore. 1.5 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard. 1.6 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use. 1.7 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee. ====== Significance And Use ====== 5.1 This test method is one of those required to determine if the presence of a medical device may cause injury to individuals during an MR examination or in the MR environment. Other safety issues which should be addressed include, but may not be limited to: magnetically induced torque (see Test Method F2213 ) and radiofrequency (RF) heating (see Test Method F2182 ). The terms and icons in Practice F2503 should be used to mark the device for safety in the magnetic resonance environment. 5.2 If the maximum magnetically induced displacement force for the specified magnetic field conditions (see Appendix X3 ) is less than the force on the device due to gravity (its weight), it is assumed that any risk imposed by the application of the magnetically induced force is no greater than any risk imposed by normal daily activity in the Earth’s gravitational field. This statement does not constitute an acceptance criterion; it is provided as a conservative reference point. It is possible that a greater magnetically induced displacement force can be acceptable and would not harm a patient or other individual in a specific case. Note 2: For instance, in the case of an implanted device that is or could be subjected to a magnetic displacement force greater than the force due to gravity, the location of the implant, surrounding tissue properties, and means of fixation within the body may be considered. For a non-implanted device with a magnetically induced force greater than the gravitational force, consideration should be given to mitigate the projectile risk which may include fixing or tethering the device or excluding it from the MR environment so that it does not become a projectile. 5.3 The maximum static magnetic field strength and spatial field gradient vary for different MR systems. Appendix X3 provides guidance for calculating the allowable static magnetic field strength and spatial field gradient. 5.4 This test method alone is not sufficient for determining if a device is safe in the MR environment.