A conventional NSI ( NASA Standard Initiator ) normally employs a hot - wire ignition element to ignite ZPP ( zirconium potassium perchlorate ) . With minor modifications to the interior of a header similar to an NSI device to accommodate an SCB ( semiconductor bridge ) , a low cost initiator was obtained . In addition , the ZPP was replaced with THKP ( titanium sub - hydride potassium perchlorate ) to obtain increased overall gas production and reduced static - charge sensitivity . This paper reports on the all - fire and no - fire levels obtained and on a dual mix device that uses THKP as the igniter mix and a thermite as the output mix .