Introduction: Accreditation agencies mandate continualbmonitor of pre-analytical, analytical and post-analytical processes. The laboratory process at Histopathology is complex and involves multiple steps. Since interpretation of slide requires good microscopic section, floaters on glass slides can be a source of error. Our study is designed to compound frequency, identify location and processes for origin of floaters and to formulate measures to reduce their incidence. Material And Methods: Twelve various commonly encountered tissue bits/ biopsies were processed together on a same day. Imprint smears taken from the sediment of water bath fluid utilized. The section were stained and examined for number, size, location and tissue type of the floater tissue wherever found. Results: All of the 12 slides revealed floaters with average of one in each section. Most (7/13) were located at edge of slide; most common tissue type of floater was displaced native type (5/13). An ovarian tumor floater found adjacent to endometrium could have led to misinterpretation. Comment: Detection of extraneous tissue contamination in slides rather than blocks implies water bath as the commoner source. A suspect tissue fragment at edge of slide is more likely to be a floater. The study highlights importance of cleaning the water bath to reduce the contamination of slides with floaters.

Keywords: Tissue Floaters; Diagnostic Errors; Contamination.