Section 864.8200 - Blood cell diluent(a)Identification. A blood cell diluent is a device used to dilute blood for further testing, such as blood cell counting.(b)Classification. Class I (general controls). This device is exempt from the premarket notification procedures in subpart E of part 807 of this chapter subject to the limitations in § 864.9 .45 FR 60635, Sept. 12, 1980, as amended at 54 FR 25045, June 12, 1989; 66 FR 38790 , July 25, 2001