Octets Key Type Content
1-4 section6Length unsigned Length of section in octets (nn)
5 numberOfSection unsigned Number of section (6)
6 bitMapIndicator codetable Bit-map indicator (see Code Table 6.0 and Note 1)
7-nn Bit-map - Contiguous bits with a bit to data point correspondence, ordered as defined in Section 3. A bit set equal to 1 implies the presence of a data value at the corresponding data point, whereas a value of 0 implies the absence of such a value.

( 1) If octet 6 is not zero, the length of the Section is 6 and octets 7-nn are not present.