Mercury Mariner 200, 225 Optimax Outboards Service Manual, 90-855348, Page 206Get this manual
Exhaust Emissions Standards Through the Environmental Protection Agency (EPA), the federal government has established exhaust emissions standards for all new marine engines sold in the U.S
is harmless gasBut carbon often combines with insufficient oxygen (one carbon atom with one oxygen atom)This forms carbon monoxide, COCarbon monoxide is the product of incomplete combustion and is dangerous, potentially lethal gas
Oxides of NitrogenNOx