1	Apex In a shaped charge the apex is the top or zenith of the liner cone.
2	Arming When the blasting engineer prepares to connect the detonator to the detonation cord in the perforating carrier he/she is said to be arming the gun. During this operation all cell phones and similar transmitting equipment must be turned off.
3	Bighole Charge A bighole charge is defined as any shaped charge that creates an entrance hole (EH) greater than 0.50".
4	Black Powder (a.k.a. gunpowder) Is a low explosive with a composition of potassium nitrate, sulfur and charcoal. Reaction velocity ranges in the 1200 to 1400 ft/sec range. Black powder is most commonly found in fireworks, but can also be used as a component in some perforating applications i.e. power charge igniters.
5	Blasting cap (a.k.a. detonator) A low gram weight explosive device used to initiate detonation of an explosive.
6	Blast Effect Generally known as the outward exertion of force on the shaped charge case during detonation. Most commercially available shaped charges loose about 70 to 80% of their effectiveness due to this reaction.
7	Booster A device designed to carry forward the explosive energy of the detonator and detonator cord to the next component in the explosive train. This device is normally used when carriers are sequenced (tandemed) together.
8	Bromine Triflouride BrF3 is a caustic fluid that reacts vigorously on contact with water and most organic materials. This fluid is used as the active ingredient in Chemical Cutting Tools and is classified as a hazardous material (under oxidizer classification).
9	Burr and Burring This refers to the external presentation of steel carrier material as seen on the exit surface of the carrier after detonation.
10	Burr Height The measure of the burr as it extends from the carrier. Excessive burr heights may indicate concerns with the carrier material or that over loading of the carrier has occurred.
11	Cap An abbreviation for detonator or blasting cap.
12	Carrot A carrot or slug is the reformed copper based liner material once used in bighole charges.
13	Cavity Liner This is the inside liner of a shaped charge. It is designed to focus the energy of the shaped charge jet stream at ignition, and to contain and maintain the integrity of the explosive powder in the charge case
14	Charge Case This is the external container for a shaped charge. Its function is to hold all the component parts of a shaped charge in proper position. The case itself can be made from a variety of materials. Typically they are made from steel or zinc.
15	Charge Interference Is the phenomenon seen when the detonation from one charge in a carrier begins to disrupt the jet stream development of a neighbouring charge. This effect is greatest in high shot density carriers. Using a XHV (extra high velocity) detonating cord has been shown to lesson this effect.
16	Clearance Is the measurable distance from the external edge of the carrier scallop to the internal edge of the casing.
17	Clip A small metal device used to secure the detonating cord to the back of the shaped charge when assembled in the loading tube.
18	Detonating Cord (a.k.a. Primacord™, detcord) A flexible plastic or rubber tube containing a core of high explosive. It is designed to carry the explosive energy to the back of each shaped charge. Perforating detcords can vary from 40 to 80 grains of explosive material per foot and can be either flat (ribbon) or round.
19	Detonation Is the initiation of the explosive train. This reaction causes an immediate change in physical characteristics (solid to a gas). Normally 1 gm of high explosive solid will create about 12,000 times its volume in gas.
20	Detonator An element in the explosive train that converts electrical or mechanical energy from the firing head to the detonator cord.
21	Dud Describes any explosive device that does not explode when initiated. Caution should always be exercised when dealing with these occurrences, as the explosive material may still be live.
22	Expendable Carriers A classification of enclosed perforating carriers designed for a one-time use. There are a wide variety of sizes, lengths and shot densities available for industry usage.
23	Explosion Refers to any controlled or uncontrolled chemical reaction that involves an immediate change in physical state from solid to a gas. Normally 1 gm of high explosive powder will create about 12,000 times its volume in gas.
24	Explosive A substance, which may be made to undergo a rapid chemical change is called an explosive. The velocity of this change will vary by the substance. Generally they are categorized into a high explosive (25,000 ft/sec reaction speed) or low explosive (3500 ft/sec reaction speed)
25	Explosive Train A combination of explosive elements physically connected together to form one complete assembly. In perforating the explosive train would contain at least three elements 1) the detonator, 2) the primacord and 3) the shaped charges.
26	Exposed Carriers These are expendable carriers designed to run where there are restrictions in the well. All charges, detonators and detonating cord employed in this system must not be sensitive to wellbore fluids in order for this system to operate correctly.
27	EBW Detonator (Exploding Bridgewire) A detonator which utilizes the shock wave from an exploding bridgewire to initiate a secondary explosive.
28	EFI (Exploding Foil Initiator) detonator which utilizes an exploding foil to accelerate a disk and initiate a secondary explosive by means of the kinetic energy in the disk.