ULC 632

This Standard applies to the construction and performance of heat shields intended to reduce the specified minimum clearances for heat producing appliances to combustible vertical construction assemblies (ie. walls, partitions). These requirements apply to regular and corner installations only. Alcove installations are not covered by this standard.
Heat shields are to be rated on a percentage clearance reduction basis (i.e. a 50 % rated heat shield is considered suitable for the reduction of required clearances by 50 %.)
Heat shields are to be designed for attachment to walls.
This Standard does not apply to heat shields for reduction of required clearances to combustible horizontal assemblies (ie. ceilings), radiant floor protection, or mantels.