Phase 1 provided specific recommendations for minimizing the distraction potential from original equipment in-vehicle interfaces that involve visual-manual interaction. The Phase 1 Guidelines focus on recommending acceptance criteria for driver glance behavior in which single average glances away from the forward roadway are 2 seconds or less and in which the sum of the durations of all individual glances away from the forward roadway are 12 seconds or less while performing a testable task, such as selecting a song from a satellite radio station.

To the extent practicable, NHTSA said, the Phase 2 Guidelines apply the Phase 1 recommendations to the visual-manual interfaces of portable and aftermarket devices.

Flow diagram summarizing the overall recommendations for both portable and aftermarket devices. Source: NHTSA. Click to enlarge.

Pairing. Assuming that the original equipment in-vehicle interface conforms to the Phase 1 Guidelines, pairing would ensure that the tasks performed by the driver while driving would meet the time-based, eye-glance task acceptance criteria specified in the Phase 1 Guidelines.

Pairing would also ensure that certain activities that would inherently interfere with the driver’s ability to safely control the vehicle would be locked out while driving. These lock outs include:

• Displaying video not related to driving;

• Displaying certain graphical or photographic images;

• Displaying automatically scrolling text;

• Manual text entry for the purpose of text-based messaging, other communication, or internet browsing; and

• Displaying text for reading from books, periodical publications, web page content, social media content, text-based advertising and marketing, or text-based messages.

Driver Mode. The Driver Mode should present an interface to the driver that conforms with the Phase 1 Guidelines and, in particular, locks out tasks that do not meet Phase 1 task acceptance criteria or are among the specified lock outs.

The purpose of Driver Mode is to provide a simplified interface when the device is being used unpaired while driving, either because pairing is unavailable or the driver decides not to pair.

NHTSA recommends two methods of activating Driver Mode depending on available technology.

• Automatic. The first option, and the one encouraged by the agency, is automatically to activate the portable device’s Driver Mode when: (1) the device is not paired with the in-vehicle system, and (2) the device, by itself, or in conjunction with the vehicle in which it is being used, distinguishes that it is being used by a driver who is driving. The driver mode does not activate when the device is being used by a non-driver, e.g., passenger.

• Manual. NHTSA has learned that technologies to detect whether a driver or passenger is using a device have been developed but are currently being refined such that they can reliably detect whether the device user is the driver or a passenger and are not overly annoying and impractical. Accordingly, the agency is proposing a second means of activation: manual activation. NHTSA sees this being a temporary option in the Phase 2 Guidelines until driver-passenger distinction technology is more mature, refined, and widely available.

Due to the close relationship between the Phase 1 and Phase 2 Guidelines, the agency is considering combining the two phases into a single document when the Phase 2 Guidelines are finalized. The agency requests comment on whether a single combined document would be easier for industry to use and the public at large to reference, or whether separate documents would be simpler. The agency is seeking public comments on its proposed guidelines.