It is true that UVA (315-380 nm)is the least damaging band and that this is where most hand held lights fall. It is also true that amber lenses enhance the flourescent image by blocking violet and blue light. The flourescence is not in ultraviolet, but other (yellow and green) bands, excited by the UV energy. Seeing the flourescence is okay.
However. UVA is cumulatively damaging to the cornea and blue light at and above the 380 nm band is cumulatively damaging to the retina and is a cause of macular degeneration. Even daylight has fairly high levels of both and UV lights have them in concentration.
It is true that carpet fiber diffuses any light, but just seeing the violet light is proof that a portion is being reflected to one's eyes. In addition, the momentary reflection off chrome, glass, porcelain or even ceramics can be as intense as having the light flick across your eyes.
Amber or blue/UV blocking lenses prevent all of that from happening. These excellent lights are far more intense than the usual flashlights and illuminate in daylight. They are far and away brighter; that is good!
But they are not harmless. No doubt any effects may happen over time, but wear eye protection for the sake of your old age. I offer glasses to customers who want to walk the rooms with me; in fact I insist. It is a matter of common sense.
Here is a good overview of the topic:
http://www.reviewofoptometry.com/continuing_education/tabviewtest/lessonid/109744/
