And it's "Noack", not NOACK.
Yes, I'm sure people were confused over what NOACK was referring to
It makes you look more credible when you spell things correctly, that's all.
People don't seem to care if it's Noack or NOACK. All the letters are there in the correct order, capitalized or not. It doesn't mean different tests whether you capitalize the letters or not.
Also, there are 4 different types of tests can be performed in accordance to the ASTM spec.
Not all of them are completely interchangeable.
A uses the Noack evaporative tester
B uses the automated non-Woods metal Noack evaporative apparatus
C uses Selby-Noack volatility test equipment
D uses Noack S2 test equipment.
A & C provides equivalent results
B&D provides equivalent results
A/C provide slightly lower results than B/D on formulated engine oils
A/C provide slightly higher results than B/D on basestocks
All of this is in the ASTM