Expected breaker temperature on a 208V 30A circuit with continuous 80% load
The breakers are likely rated for 40C (104F) ambient.That would be the meaning of 40C marked on the breaker. They are likely rated for connection to wire that has a 60/75C insulation temperature rating. That would also be marked on the breaker. The surface temperature of the breaker can be expected to be higher than the ambient temperature. A surface temperature of 47C should not be a problem if the ambient temperature is 40C, but 47C surface temperature in a 20C ambient could be a problem. That would mean the surface temperature has a 27C rise and would reach 67C in a 40C ambient. However the following information seems to indicate that the breaker is allowed to get hotter than the wire.

UL Surface Temperature Rise Limits

Non-metallic 60 deg. C

Metallic 35 deg. C

UL Terminal Temperature Rise

80% Rated CB 50 deg. C

100% Rated CB 60 deg. C

The above information was found in another forum, not directly from UL.