The most common common I get whenever I build a radiator cover - “that’s a fire hazard”.Heat can be scary. And putting something over something that’s hot can indeed be dangerous. We checked with our local heating specialist before I built any of these and luckily for us we’ve got a source of heat that is the least hazardous when it comes to radiators and baseboard heating. We get our heat from hot water like hot water from the tap. So the radiators don’t get super hot, but they retain the heat

When two types of coolant been mixed, it will result of this substance in the radiator reservoir and needs to be flushed completely | Alimech