I don't see why they can't be - you can make cables sheathed with the same basic material (PE) that many water pipes are made of after all.
The Americans have been using building air ducts to route data cables for generations - and have a special 'plenum grade' cable sheaths to suit (mostly to stop poisonous fumes be created during a fire that could then be carried to people's lungs throughout the building by the air duct), so the idea of slightly specialised cables for routing in human supply routes isn't new.
I don't see why they can't be - you can make cables sheathed with the same basic material (PE) that many water pipes are made of after all.
The Americans have been using building air ducts to route data cables for generations - and have a special 'plenum grade' cable sheaths to suit (mostly to stop poisonous fumes be created during a fire that could then be carried to people's lungs throughout the building by the air duct), so the idea of slightly specialised cables for routing in human supply routes isn't new.
