It was my first day of Clinicals. My preceptor at Detroit Receiving presented me with a lipoma to gross and a brand new ruler. I dictated out "5.2 x 4.3 x 3.7 cm" for the well-encapsulated glistening yellow adipose tissue. The outer surface was inked black and the specimen was serially sectioned to reveal glistening yellow cut surfaces. One section per cm with two sections submitted per cassette. I closed the cassettes and turned to my preceptor. She looked back with a face that said "you missed something". I started rambling off things like "three patient identifiers, asset reconciliation, 3mm section thickness." I pulled the specimen back out and reexamined the cut surfaces. Stumped, I turned back to her in defeat. "You weren't measuring starting from zero", she said as she put the ruler back in my hand. I looked down at the ruler and it had 0.3 cm of blank plastic before the scale started. My preceptor took out a pair of scissors and trimmed off the 0.3 cm, "always check that your instruments are ready for service." She went on to explain that every mm matters.
The end of each Yaamo ruler is through the 0 cm and 15 cm markings. But don't take our word for it, inspect your instruments' readiness.