The Ammonium Nitrate Materials (High Nitrogen Content) Safety Regulations 2003

5.  Filling and charging the steel tube. (see Drawings 2 and 3)

(a) The test sample, the steel tube and the booster charge must be conditioned to temperatures of 20 (± 5) °C. 16 to 18 kg of the test sample are needed for two detonation tests.

(b) Place the tube upright with its square bottom plate resting on a firm, flat surface, preferably concrete. Fill the tube to about one-third of its height with a portion of test sample and drop it 10 cm vertically onto the floor five times to compact the prills or granules as densely as possible in the tube. To accelerate compaction, vibrate the tube by striking the side wall with a 750 to 1,000-gram hammer between drops for a total of 10 times.

(c) Repeat this charging method with another portion of the test sample.

(d) Finally, a further addition shall be made such that, after compaction by raising and dropping the tube 10 times and a total of 20 intermittent hammer blows, the charge fills the tube to a distance of 70 mm from its orifice.

(e) The filling height of the sample must be adjusted in the steel tube so that the booster charge (prepared by either of the two methods in paragraphs 3(1) and (2) above) to be inserted later will be in close contact with the sample over its entire surface.

(f) Insert the booster charge into the tube so that it is in contact with the sample; the top surface of the wooden disc must be 6 mm below the end of the tube. Ensure essential close contact between explosive and test sample by adding or removing small quantities of sample. As shown in Drawings 2 and 3, split pins should be inserted through the holes near the open end of the tube and their legs opened flat against the tube.