What is the maximum distance between devices that must be "in sight from" one another?

The maximum distance between devices that must be "in sight from" one another is typically defined as 50 feet. This requirement is often applied to ensure proper visibility and communication between devices in systems such as alarm signals or fire alarm systems, where clear visual identification is necessary for safety and operational efficacy. Keeping devices within this specified distance helps to maintain immediate awareness of alarms or indications and facilitates prompt action when needed.

Maintaining this distance is crucial in scenarios where visual confirmation is important, such as manual activation or monitoring. This guideline is in place to prevent situations where devices may be out of sight, which could lead to delays in response or the failure to act, potentially compromising safety or the efficacy of the system.

In contrast, other distances mentioned in the choices either fall short of this requirement or exceed it without being standard practice under most applicable codes and regulations. Thus, the chosen answer aligns well with established safety protocols in the industry.