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Re: Formula for calculating cat efficiency?
Posted to Emissions Forum on 7/8/1999 7 Replies

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Hello Norm,

Precat divided by the amount of change.

HC preCAT = 100 ppm, postCAT = 10 ppm, CAT HC eficiency = 90%. (100-10)/100 = 90/100 = .90 = 90 percent.

CO precat = 1.0%, postCAT = 0.1, CAT ... Login to read more.

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