What should technicians refer to for determining the correct distance for installing an overfill-prevention device?

Technicians should refer to a placement chart to determine the correct distance for installing an overfill-prevention device. A placement chart provides specific guidelines and measurements that are critical for the proper installation of these devices, ensuring they are positioned at the appropriate heights and distances to effectively prevent overfilling during tank operations. By adhering to the specifications outlined in the placement chart, technicians can maintain compliance with safety regulations and enhance the overall reliability of the system.

Other resources, such as a measuring chart, gauging chart, or units, do not specifically address the installation distances needed for overfill-prevention devices. While they may provide helpful information in other contexts, the placement chart directly targets the requirements for these particular devices, making it the most relevant choice for technicians in this scenario.