When you have a pacemaker implanted, stay away from devices with large magnets or magnetic fields that can be created from motors of cars or boats. An MRI is a diagnostic imaging tool used to take images of your body using magnets. Some pacemaker and ICD devices are approved to have an MRI but always talk with your provider before having this test to make sure it is safe for you. Magnetic fields can be created by other machines which could affect the normal function of your device. Avoid high-voltage radar machines, such as radio or T.V. transmitters, electric arc welders, high-tension wires, radar installations, or smelting furnaces.