In a move that may signal a further weakening of the coal tar sealant industry, one of their standards for residential applications recently lapsed. Interesting since one of the sealant industry's lofty claims is that their product has an ASTM standard. If you're not familiar with the organization, ASTM (American Society for Testing and Materials) develops standards for all kinds of products and materials.
In July the industry let the standard for residential sealants drop. The official title is: ASTM D6946-03 Standard Specification for Emulsified Refined Coal-Tar (Driveway Sealer, Ready to Use, Primarily Residential Grade) Apparently these standards need to be reviewed or updated every 8 years or they lapse. They call this being "withdrawn."
It is funny that a standard developed by industry chose to refer to it as "Coal-Tar" eight years ago, but has now all but dropped any reference to this term.
Additional standards that apply coal tar sealants include:
C136 Test Method for Sieve Analysis of Fine and Coarse Aggregates
C142 Test Method for Clay Lumps and Friable Particles in Aggregates
D140 Practice for Sampling Bituminous Materials
D490 Specification for Road Tar
D2939 Test Methods for Emulsified Bitumens Used as Protective Coatings
D5727 Specification for Emulsified Refined Coal Tar (Mineral Colloid Type)