Ø1996 GRI tested 6 models
of compliance level “Emission Analyzer”. Results of testing showed consistent
laboratory performance, typically within 1%.
Ø2000 EPA ETV tested
seven multi-gas models
Ø 6 within
about 1%
Ø 1 within
about 5%.
ØEuropean TUV – Approval
for official NOx testing since early 1990s (on-going approval
process)