(1) Cord selection. Care must be taken to select a detonating cord consistent with the:

(a) Type and physical condition of the drill hole;

(b) Stemming;

(2) Handling. A detonating cord must be handled and used with:

(a) The same respect and care given to other explosives;

(b) Care to avoid damaging or severing the cord during and after loading and hooking up.

(3) Calculating quantity and distance.

(a) For quantity and distance purposes, a detonating fuse (up to sixty grains per foot) should be calculated as equivalent to nine pounds of high explosives per one thousand feet;

(b) Heavier cord loads should be rated proportionally.

(4) Trunk lines.

(a) Detonators for firing the trunk line cannot be brought to the loading area or attached to the detonating cord until everything else is ready for the blast;

(b) All detonating cord trunk lines and branch lines must be free of loops, sharp kinks, or angles that direct the cord back toward the oncoming line of detonation;

(c) Trunk lines in multiple row blasts must make one or more complete loops, with cross ties between loops at intervals less than two hundred feet.

(5) Connections.

(a) Detonating cord. All detonating cords must be:

(i) Competent and positive in accordance with the manufacturer's recommended specifications.

(ii) Kept at right angles to the trunk lines.

(iii) Inspected before firing the blast.

(b) Knots.

(i) Knot or other cord-to-cord connections must be made with a detonating cord where the explosive core is dry.

(ii) All detonator cord knots must be tight.

(i) A detonator or electric detonator must be taped or securely attached along the side or end of the detonating cord. The detonator end containing the explosive charge must be pointed in the direction of the detonation.

(ii) Manufacturer's recommendations must be followed when short interval delay electric detonators are used with a detonating cord.

(iii) Manufacturer's recommendations must be followed when detonating cord millisecond delay connectors are used with a detonating cord.

(iv) The line of detonating cord extending from a drill hole or a charge must be cut from the supply spool before loading the remainder of the drill hole or placing additional charges.

PDFWAC 296-52-67100

Use of detonating cord.