At what engine speed may the catalytic converter stop working properly?

Common theory questions

If you exceed 3,000 rpm the catalytic converter can stop working properly. If this happens, the emission of substances hazardous to health and the environment, such as hydrocarbons and nitrogen oxides, increases.

Drive in the following way to not exceed 3 000 rpm:

Upshift early.
Skip gears.
Drive in the highest possible gear.
Do not accelerate at more than half-throttle.

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