Section 211.1567  Critical Use and Line Sealer Maskant

"Critical use and line sealer maskant" means a temporary coating, not covered under other maskant categories, used to protect selected areas of aerospace parts from:

strong acid or alkaline solutions such as those used in anodizing, plating, chemical milling, and processing of magnesium, titanium, or high strength steel;

high-precision aluminum chemical milling of deep cuts; and

aluminum chemical milling of complex shapes.

Materials used for repairs or to bridge gaps left by scribing operations (i.e., line sealer) are also included in this definition.

(Source:  Added at 45 Ill. Reg. 3509, effective March 4, 2021)