Over the course of the last year, Amazon began rolling out a new worker safety wearable to 25+ sites. From the looks of it, the Robotic Tech Vest is really more like a pair of suspenders attached to an electronic utility belt. The Amazon Robotics-designed product was created to keep workers safe when they need to enter a space in order to fix a robotic system or retrieve fallen items. Built-in sensors alert Amazon’s robotic systems to the wearer’s presence, and they slow down to avoid collision.

The vest is designed to work in tandem with the robots’ existing obstacle avoidance detection.

“All of our robotic systems employ multiple safety systems ranging from training materials, to physical barriers to entry, to process controls, to on-board,” Amazon Robotics VP Brad Porter told TechCrunch. “In the past, associates would mark out the grid of cells where they would be working in order to enable the robotic traffic planner to smartly route around that region. What the vest allows the robots to do is detect the human from farther away and smartly update its travel plan to steer clear without the need for the associate to explicitly mark out those zones.”

Safety has, of course, become a major concern when it comes to dealing with human/robotic interactions at the work place. As OSHA notes, “Studies indicate that many robot accidents occur during non-routine operating conditions, such as programming, maintenance, testing, setup, or adjustment. During many of these operations the worker may temporarily be within the robot’s working envelope where unintended operations could result in injuries.”

In December, two dozen Amazon warehouse employees were sent to the hospital in a bear repellent-related incident in which a robot may have been involved. As robot and human collaborations become increasingly commonplace, it’s a good idea to take a better-safe-than-sorry approach to working alongside these big metal machines.

Porter notes that tests with the vest have a “huge success,” with “more than one million unique activations” having been recorded with the systems it’s deployed thus far.