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Are all hot tub covers you get with a hot tub astm covers.
ASTM uses UL guidelines I believe in safety testing. Not 100%, but I've noticed that every tub that is ASTM approved also has UL logo as well.
That's an expensive marketing driven plan since most people don't even question cover quality before the purchase. UL has a hefty charge. I would think they would just bypass altogether since already ASTM.
Yeah it looks like they are by choice and separated. I wonder if the standards are the same?