y: The number of years (integer, >= 0, not restricted)
m: The number of months (integer, >=0, not restricted)
d: The number of days (integer, >=0, not restricted)
h: The number of hours (integer, >=0, not restricted)
n: The number of minutes (integer, >=0, not restricted)
s: The number of seconds or fraction of seconds (real or integer, >=0, not restricted). If fractions of a second are used, SCORM further restricts the string to a maximum of 2 digits (e.g., 34.45 – valid, 34.45454545 – not valid).
The character literals designators P, Y, M, D, T, H, M and S shall appear if the corresponding non-zero value is present.
Zero-padding of the values shall be supported. Zero-padding does not change the integer value of the number being represented by a set of characters. For example, PT05H is equivalent to PT5H and PT000005H.
Example
P1Y3M2DT3H indicates a period of time of 1 year, 3 months, 2 days and 3 hours
PT3H5M indicates a period of time of 3 hours and 5 minutes