We have many Customers who have installed their CableClear around the back of their fireplaces where the materials will get warm, but are not exposed to naked flames.
The CableClear hose is made from polyurethane material and has a recommended temperature operating range of -40°C up to +90°C (short term up to +125°C). We carefully selected the material to meet all the engineering performance requirements for flexibility and durability in both very warm and very cold climates.
In addition the CableClear hose has a flammability rating of UL94 v-0 which exceeds (is better than) the V-1 flammability standard for normal PVC electrical conduits.
Please note that if there is any chance of your in-wall cable management solution being exposed to a naked flame we would strongly recommend you to explore other ways of achieving your purpose.