Mantel shields - anyone know the regulations?

Does anyone know the particular regulations for mantel shields? Required dimensions? My stove is a bit too close to my mantel. I tried it without a shield and it is getting a bit too toasty for my liking when I run her up around 600 degrees. I have been playing around with temporary shields from

HomeSaver Mantel Shield- We have an exellent selection of Fireplace mantels. Find luxury mantles and economy mantels to fit every style or budget.

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Why does Captain America so often throw his shield while (at least, as I know) his shield is not the same as Thor's hammer? It returns when Thor summons it. - Quora

HomeSaver Mantel Shield- We have an exellent selection of Fireplace mantels. Find luxury mantles and economy mantels to fit every style or budget.

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Non factory heat shield for mantel

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How to Protect Your Fireplace Mantel From Heat - Dengarden

Custom Fireplace Hood - 24 Gauge Steel. Transform your fireplace into the centerpiece it deserves to be with our exquisite Custom Fireplace Hood.

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Heavy-Duty Construction - Premium design for long-term durability Convenient - Directs heat around mantels and surrounds to efficiently protect

Kingsman I33CS Mantel Clearance Shield for IDV26 Direct Vent Gas Insert

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HomeSaver Mantel Shield- We have an exellent selection of Fireplace mantels. Find luxury mantles and economy mantels to fit every style or budget.

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