The internal structure of a Boolean operand is illustrated in Boolean Operand.

Boolean operations are performed on a bit-by-bit basis on all 48 bits of a Boolean operand. The one exception is the NOT operation performed on an arithmetic relation, where NOT is performed on the low-order bit (bit zero), but not necessarily on the other 47 bits. However, when a Boolean operand is referenced as a whole, only the low-order bit (bit zero) is significant (0 is FALSE, 1 is TRUE).

In Boolean Operand, the V's indicate that each bit of the entire 48-bit Boolean operand can be used to store an individual Boolean value. The individual bits can be referenced by using the <partial word part> and <concatenation> constructs.