What measure is relevant to minimize risks associated with reflections in laser use?

Implementing barriers and protective curtains is an effective measure to minimize risks associated with reflections in laser use. These barriers can help prevent laser beams from bouncing off reflective surfaces and potentially reaching unintended areas or individuals. By creating a physical block to the laser's path, barriers and curtains significantly reduce the chances of accidental exposure from reflections, thus enhancing overall safety in environments where lasers are utilized.

The other options, while they may have relevance in a general sense, do not specifically address the issue of reflections. Conducting regular eye tests is important for monitoring potential damage from laser exposure, but it doesn't prevent the risk itself. Increasing the laser's intensity would actually heighten risks both from direct exposure and reflections. Reducing operating hours may decrease exposure time, but it does not directly tackle the problem of reflections in the laser environment.