It is recommended to use the string codes from the below table since this makes the data human readable.

Unit Code	Unit String
1	mmol/L
10	cells/µL
11	µkat/L
12	%
13	µg/L = ng/mL
14	mg/24h
15	mg/mmol
16	fl (Femtoliter)
17	µg/mL = mg/L
2	g/L
3	g/dL
4	mg/dL
5	IU/L (u/L)
6	µmol/L
7	INR
8	1E+9/L
9	1E+6/L
99	no units (e.g. for Dipstick results)