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Two words are used interchangeably, level and flatness. The American Institute of Architecture, and most materials manufacturers specify the amount of difference off of plane that is acceptable for their product. But this doesn’t account for undulations common in concrete.
An acceptable tolerance of 3/16 inch in 10 feet does not leave a lot of room. When a sub-floor slopes down ¼ inch in 2 feet and then up a gain, this represents a slope of 1-1/4 inch in 10 feet, a violation of the standard.