The FAA has approved a new AVGAS standard for use for aircraft engines that currently use 100LL.
The new specification, called 100VLL (Very Low Lead) contains 19% less lead than the current specification.
It has determined that grade 100VLL meets all the performance requirements of grades 80, 91, 100, and 100LL and will perform identically in existing engines (aircraft). The color of VLL will be blue, and identical to 100LL.
Information taken from Nov. 2011 Business and Commercial Aviation, page 22.
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