Section 892.1970 - Radiographic ECG/respirator synchronizer(a)Identification. A radiographic ECG/respirator synchronizer is a device intended to be used to coordinate an x-ray film exposure with the signal from an electrocardiograph (ECG) or respirator at a predetermined phase of the cardiac or respiratory cycle.(b)Classification. Class I (general controls). The device is exempt from the premarket notification procedures in subpart E of part 807 of this chapter subject to § 892.9 .55 FR 48444, Nov. 20, 1990, as amended at 65 FR 2323 , Jan. 14, 2000