Primaflex detonating cord consists of a core of pentaerythritol-tetranitrate (PETN) enclosed in a tape which is wrapped with textile and / or synthetic yarns. It is then enclosed in a tubular cover of coloured (orange in N.Ireland) plastic, giving a strong flexible cord which is waterproof and light in weight. Primaflex may be initiated by a detonator of No.6 strength or greater. It has a velocity of detonation of 5,500 mps.
12 g/m & 20g/m Primaflex detonating cord is used in surface blasting mainly as an in-hole initiator of explosives when decking the column charge. It may also be used as a trunk line for the initiation of a number of holes, but this is not recommended in sensitive locations where noise could be a problem.
NOTE:- Primaflex is not used for initiating emulsion explosives.