A severe tire damage device is the row of spikes, blades, etc. used to keep people from driving over something, or to make sure they only go over it one way. It may be abbreviated oh-so-cleverly as STD, as is seen in army driving manuals.

One way STDs are composed of triangles, where the long side can be safely driven over and the short, concave side destroys an offending tire. Like so:

             \''''~~~~,,,,          
______________\           ''''~~~~,,,,_______________  

Two way STDs are more spike shaped, but with enough thickness to support the weight of a car:

            /\                          
           |  |            
__________/    \_____________

Severe tire damage devices are commonly found on military bases, outside of prisons, and in other high security environments. They are also an alternative for controlling entrance and exit from a parking lot, as they are much more effective than barriers that raise and lower (and can be driven right through). STDs on parking lots are often marked with the sign Do Not Reverse! Severe Tire Damage Will Result! An STD turned the wrong way can lead to all sorts of wonderful anarchy, as shown in Fight Club.

The stinger is an STD device used by police to deflate tires during a car chase. See TallRoo's writeup under stinger for more.

Log in or register to write something here or to contact authors.