What can be substituted for CMP?

The correct choice is CMR, which stands for Communications Multipurpose Cable, Riser. It is a type of cable that is suitable for vertical spaces in buildings, where fire safety is a concern. CMR cables are designed to prevent the spread of fire between floors in a building, making them a viable substitute for CMP (Communications Multipurpose Cable, Plenum), which is rated for use in plenum spaces, where air circulation for heating and air conditioning systems occurs.

Substituting CMP with CMR is acceptable because CMR meets certain fire safety requirements, though it is less stringent than the CMP rating. This means that while it can be used in certain applications, there are specific conditions that should be observed, such as the placement and types of wiring.

The other options, while relevant in different contexts, do not adequately meet the same safety standards as CMR. As such, recognizing the appropriate circumstances in which to use these alternative cable types is essential for compliance with building codes and fire safety regulations.