SPD is an acronym we don’t see too often, but it’s good to be aware of this code. It stands for Security Precaution Designator, and you can see a little more about it here. Generally, an SPD indicates someone is a risk for escape or staff assault.
SPDs can impact eligibility for housing assignments and programs. We don’t know enough about these, and we are pretty certain there are other designators used in a less formal manner.