Class I may refer to:
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Class I antiarrhythmic
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Class I electrical appliance, a device constructed according to electrical grounding specifications in the
IEC 60536-2 standard
*
Class I bacteriocin, a type of toxin produced by some bacteria
*Class I
biosafety cabinet
*Class I laser, a type of eye-safe laser defined in the
ANSI Z136 standard
*
Class I rail carrier
In the United States, railroad carriers are designated as Class I, II, or III, according to annual revenue criteria originally set by the Surface Transportation Board in 1992. With annual adjustments for inflation, the 2019 thresholds were US$ ...
, a type of major freight railroad company in Canada
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Class I railroad, a type of major freight railroad company in the United States
See also
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Class 1 (disambiguation) Class 1 may refer to:
* Class I railroad, a term used in North American railroad size classification
* Class 1 Touring Cars, an FIA classification for cars in motor racing
* Class 1 World Powerboat Championship
* Classes of U.S. Senators
* SCORE ...
*
I class (disambiguation)
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