The NASA Standard Detonator (NSD) is a device used by NASA

NASA

The National Aeronautics and Space Administration is the agency of the United States government that is responsible for the nation's civilian space program and for aeronautics and aerospace research...

 for applications where a charge must be detonated, usually in conjunction with frangible nut

Frangible nut

The frangible nut, commonly confused with an explosive bolt, is a component used in many industries, but most commonly by NASA to sever mechanical connections. It is, by definition, an explosively-splittable nut...

s as a release mechanism. NSDs have been used since the Gemini

Project Gemini

Project Gemini was the second human spaceflight program of NASA, the civilian space agency of the United States government. Project Gemini was conducted between projects Mercury and Apollo, with ten manned flights occurring in 1965 and 1966....

 program, and were used for the Space Shuttle program

Space Shuttle program

NASA's Space Shuttle program, officially called Space Transportation System , was the United States government's manned launch vehicle program from 1981 to 2011...

, including the Solid Rocket Booster

Space Shuttle Solid Rocket Booster

The Space Shuttle Solid Rocket Boosters were the pair of large solid rockets used by the United States' NASA Space Shuttle during the first two minutes of powered flight. Together they provided about 83% of liftoff thrust for the Space Shuttle. They were located on either side of the rusty or...

 (SRB) separation from the External Tank

Space Shuttle external tank

A Space Shuttle External Tank is the component of the Space Shuttle launch vehicle that contains the liquid hydrogen fuel and liquid oxygen oxidizer. During lift-off and ascent it supplies the fuel and oxidizer under pressure to the three Space Shuttle Main Engines in the orbiter...

, as well as the SRB Range Safety System. Hi-Shear is the primary provider for the NSD's which were used on the Space Shuttle.