CFR › Title 21 › Part 868 › §868.188021 CFR §868.1880Verified against eCFR.gov as of June 20, 2026View official text on eCFR.gov ↗Copy link(a)Identification. A pulmonary-function data calculator is a device used to calculate pulmonary-function values based on actual physical data obtained during pulmonary-function testing.(b)Classification. Class II (performance standards).