High Quality Content by WIKIPEDIA articles! The NASA Standard Detonator (NSD) is a device used by NASA for applications where a charge must be detonated. NSDs have been used since the Gemini program, and are still used for the Space Shuttle program. Current usage includes the Solid Rocket Booster (SRB) separation from the External Tank, as well as the SRB Range Safety System. Hi-Shear is the primary provider for the NSD's which are used on the Space Shuttle.