A commercially manufactured metal blade with these characteristics: width – 1-1/2 to 3”; length
– 3 to 5”; thickness – 30 to 50 mils. The putty knife is acceptable for use if the thickness at end of
the blade is not less than 25 mils or 75% of its original thickness, whichever is greater. It shall not
be used if the edge is nicked or gouged, or if dry paint or other material is present along the edge
that would prevent the blade from making intimate contact with the surface. When used to test
paint, mill scale, or rust remaining on the surface after cleaning, the blade shall be held flat
against the surface and at a maximum of 45 degrees to the surface. The corners of the blade shall
not be used to dig at the residues.
