Decree of the Czech Mining Office No. 316 / 1998 Coll.
Order of the Czech Mining Authority establishing a method for detecting explosives of chemicals and chemical preparations
Valid
Order
Effective from 01.01.1999
Text versions:
01.01.1999
31.12.1998
316
DECLARATION
Czech Mining Office
of 15 December 1998
laying down a method for detecting explosives of chemicals and chemical preparations
The Czech Mining Authority provides pursuant to § 4 (1) (a) of Act No. 157 / 1998 Coll., on Chemicals and Chemical Products and amending certain other laws:
Basic concepts
For the purposes of this decree, it shall be considered as:
(a) explosive substances (1) such chemicalsubstances (2) or chemical preparation (3) (hereinafter referred to as "substance") which are capable of exploding by heat or which, in view of the possibility of exploding, is sensitive to impact or friction in the instrument referred to in the Annex or is more sensitive to impact or friction than 1.3-dinitrobenzene in an alternative instrument;
(b) reference substance
1. crystalline 1.3-dinitrobenzene which passes through a sieve of 0,5 mm mesh size for impact and friction sensitivity testing;
2. perhydro-1,3,5-trinitro-1,3,5-triazine (referred to as RDX or hexogen or cyclonite - CAS 121-82-4), recrystalled from aqueous cyclohexanone, sewn wet to 250 µm and caught in 150 µm nets, dried at 103 ± 2 ° C for 4 hours, for the second series of tests according to § 3 (3) (b) and (c).
Preliminary tests
(1) Prior to conducting the tests, preliminary tests shall be carried out to ensure safety.
(2) The preliminary tests shall be carried out with very small samples of the substance, approximately 10 mg, by heating the non-closed substance in the flame of the gas burner, impact in any device and friction using a mallet against the pad or in any other friction sensitivity test device. The purpose of the preliminary tests is to determine whether the substance is so sensitive and explosive that the prescribed sensitivity tests, in particular the heat sensitivity test, must be carried out using protective measures to prevent injury to the test person.
(3) The results of the preliminary tests do not serve to evaluate the explosive performance of the substance.
Explosive detection method
(1) The method for detecting the explosive of the substance listed in the Annex (hereinafter referred to as the method) provides for a test procedure to determine whether the substance is sensitive to heat, impact or friction from the point of view of explosion under the conditions laid down in this Decree.
(2) The method provides data for assessing the possibility of causing an explosion through the effects of the initiatives referred to in paragraph 1. It is not used to determine whether a substance is capable of exploding under any conditions.
(3) The substance must be subjected to the following tests:
(a) a heat sensitivity test at which the substance is heated in a steel tube closed by apertures. This test shall determine whether the substance is liable to explode under intense heating and prescribed sealing conditions,
(b) the impact sensitivity test at which the substance is tested by the weight of the prescribed mass released from the prescribed height;
(c) a friction sensitivity test in which a solid or pasty substance is tested by friction between standard surfaces under prescribed load conditions and mutual movement. For liquids, no friction test is performed.
The tests shall be carried out according to the methodology set out in the Annex.
(4) Alternative instruments may also be used in the tests referred to in paragraph 3, provided that they are internationally recognised and that the results obtained correspond to the results obtained on the instruments listed in the Annex.
(5) The tests referred to in paragraph 3 shall not be carried out if, on the basis of an expert assessment, the substance is clearly concluded that the substance cannot rapidly decompose under the development of gases and heat release and therefore does not pose a risk of explosion.
Evaluation
(1) The substance is evaluated as explosive within the meaning of this test if a positive result has been obtained in one of the tests referred to in Article 3 (3) or if the test result is more sensitive than the sensitivity of the reference substance using alternative instruments.
(2) The positive result of the test shall be the explosion, the speech of which is given in the Annex.
Test report
(1) A report shall be drawn up on the test.
(2) The test report shall include, where possible, in particular:
(a) labelling, chemical composition, purity and moisture of the test substance;
(b) the physical form of the sample and whether the sample was crushed, ground or sieved;
(c) data from the heat sensitivity test, such as sample weight and number of fragments;
(d) the phenomena observed during the impact sensitivity test or the friction sensitivity test, such as the formation of a significant amount of smoke or complete decomposition without bang, flames, sparks, bang or cracking;
(e) the results of each type of test;
(f) justification for the use of the alternative apparatus and evidence of comparability of the results obtained with the results obtained with the apparatus listed in the Annex;
(g) notes which may be relevant for the correct assessment of the results, such as references to tests of similar substances.
(3) The test report shall also show all results considered to be incorrect, abnormal or unrepresentative. If it is not possible to explain such a result in a qualified manner, it shall be accepted as achieved and the substance evaluated in a manner appropriate to the result achieved.
Removal of doubts
If there is doubt about the result of the tests, a further test shall be carried out, either a test to determine the ability to spread a detonative reaction or a sensitivity test to internal heat stimuli, or both. These tests shall be carried out according to an internationally accepted methodology. 4) The test report shall state the type and results of these additional tests as well as the justification for the use of the test chosen and the methodologies used.
Efficacy
This Decree shall take effect on 1 January 1999.
Chairman:
Doc. JUDr. Ing. Makarius, CSc.
Annex to Decree No. 316 / 1998 Coll.
Description of method for detection of explosive substances and chemical preparations
POINT 1. Heat sensitivity test
a. The device consists of a single-use steel tube with a reusable closing device (Figure 1) installed in a heating and protective device. Each tube is made of steel sheet. Its inner diameter is 24 mm, length 75 mm and wall thickness 0,5 mm. At the open end of the pipe, the flange is used to close the pipe by assembling the aperture. The assembly is made up of a orifice with a central orifice resistant to the pressure attached to the pipe by means of a two-part screw connection (nut and threaded flange). The nuts and threaded flange are made of chromium-manganese steel, which is non-sparkle up to 800 ° C. The apertures are 6 mm thick, they are made of refractory steel and form a series according to the size of the holes.
b. The substance is usually tested in the condition in which it is supplied. In some cases, e.g. when pressed, cast or otherwise compacted, it may be tested after crushing.
For solids, the mass of the substance used in each test shall be determined in two stages. In the first stage, the weighed tube shall be filled with 9 cm3 of the substance and pressed with a force of 80 N throughout the pipe cross-section. For safety reasons or in cases where the physical form of the sample may be changed by compression, another way of filling may be used; For example, if the substance is very sensitive to friction, compression is not appropriate. If the substance is compressible, an additional quantity of the substance shall be added and pressed until the tube is filled within 55 mm of the upper edge. The total amount of substance used for filling up to 55 mm from the upper edge shall be determined and an additional 2 parts shall be added each with a force of 80 N. The substance is then either added and pressed as necessary, or removed so that the tube is filled to a level of 15 mm from the upper edge. The determined total mass of the substance is the basis for the implementation of the second stage. In this case, a third of the mass recorded in the first stage is first inserted into the tube and compressed. A further 2 parts shall be added, pressed with a force of 80 N and the substance shall be added or removed in the tube to a level of 15 mm from the top of the pipe if necessary. The quantity of solid determined in the second stage shall be used for each experiment; the filling shall be carried out with 3 equal quantities and each shall be compressed to a volume of 9 cm3, regardless of the force required. The spacing rings can be used to facilitate this.
The liquids and gels shall be filled into a tube up to 60 mm high. Particular attention should be paid to gels to avoid cavities. A threaded flange shall be applied from the bottom of the tube, a suitable aperture shall be inserted and the nut shall be applied after application of the molybdenum disulfide lubricant. It is necessary to check whether a substance remains caught between the flange and the screen or in the threads.
The filled and closed pipe shall be heated with propane collected through the flow meter from an industrial cylinder with a pressure regulator adjusted to range 6 to 7 kPa. Propane is divided evenly into 4 burners through the distribution pipes, which is verified visually by the burning of the burners. The burners are located around the test tube (Figure 1). 4 burners have a total consumption of approximately 43,2 dm3 propane per minute. Alternative fuel and burners may be used, but the heating speed shall be the same as shown in Figure 3. For all devices, the heating rate shall be checked regularly using tubes filled with dibutylphthalate (Figure 3).
c. Each test shall be carried out until the tube breaks or the heating time is 5 minutes.
First, a series of 3 tests shall be carried out with a 6 mm aperture diameter and, if no explosion occurs, a second series of 3 tests shall be carried out with a 2 mm aperture diameter. If the explosion occurs in any test series, further tests shall not be required.
d. The effect of the explosion is to tear the pipe into 3 or more parts, some of which may be connected with each other by narrow strips of metal (Figure 2). A test where fewer parts are produced or no parts are produced shall be considered as non-explosion testing.
POINT 2. Impact sensitivity test
a. The base parts of the usual drop-hammer devices are a grey iron block with a base, an anvil, a pole, a guide bar, a hammer, a holding and release device and a sample holder (Figure 4). The steel pad (anvil) with a diameter of 100 mm and a height of 70 mm is bolted to the top of the steel-cast-iron block with a length of 230 mm, a width of 250 mm and a height of 200 mm with a base (cast-iron) plate of 450 mm, a width of 450 mm and a height of 60 mm. The column formed by a seamless steel pipe is attached to the back of the steel-cast block by a holder. 4 screws anchor a concrete block device with dimensions of 60 x 60 x 60 cm in such a way that the guide bars are exactly perpendicular and the drop weight falls freely. It is advisable to use a weight of 5 kg and 10 kg of solid steel. The impact head of each weight is of hardened steel HRC 60 to 63 with a minimum diameter of 25 mm.
The test sample shall be sealed in a test preparation consisting of 2 coaxial steel cylinders placed above it and a lead casing consisting of a hollow steel cylinder. Full steel cylinders with a diameter of 10 (-0,003, -0,005) mm and a height of 10 mm have polished surfaces, rounded edges with a radius of curvature of 0,5 mm and hardness of HRC 58 to 65. The hollow cylinder shall have an external diameter of 16 mm, a polished hole with a diameter of 10 (+ 0,005, + 0,010) mm and a height of 13 mm. The assembled test product shall be placed on a 26 mm diameter and 26 mm diameter interchangeable platform centred on a centre ring with smoke openings.
b. The sample volume shall be 40 mm3 or such volume as is suitable for alternative equipment. The solids are tested dry and prepared as follows:
1. the powder shall be sifted through a sieve with a mesh size of 0,5 mm; any portion passing through the sieve shall be used for testing;
2. pressed, cast or otherwise compacted substances are crushed into small pieces and sown; for the test of a substance, a sieved particle size of 0,5 to 1 mm shall be used as a representative sample of the parent substance.
Substances supplied as paste shall be tested, preferably in the dry state or after removal of the maximum amount of diluent. Liquid substances shall be tested with a gap of 1 mm between the upper and lower steel cylinders.
c. For a series of 6 tests, a 10 kg mass shall be released from a height of 0,40 m (40 J). If the explosion occurs during these 6 tests at 40 J, a further series of 6 tests shall be carried out with a weight of 5 kg from a height of 0,15 m (7,5 J). For other establishments, the sample shall be compared with the selected reference substance [§ 2 (b) of the Decree] using the specified procedure. 5)
d. The result is considered positive if the explosion is recorded in any test. The explosion is a bang or a flame. A change in the colour of the substance or odours shall not be regarded as an explosion.
POINT 3. friction sensitivity test
a. The friction device (Figure 5) consists of a base plate of cast steel on which the friction device is fixed. It consists of an immobile porcelain pin and a moving porcelain plate. The porcelain plate is mounted on two guide bars. The sleigh is connected to the electric motor with a hoop, an eccentric cam and a suitable gearing so that the porcelain plate exercises the movement back and forth of the 10 mm track length under the porcelain pin. The porcelain pin can be loaded with either 120 N or 360 N.
Straight porcelain plates are made of white technical porcelain with a roughness of 9 to 32 μm of 25 mm, 25 mm wide and 5 mm high. The cylindrical porcelain pin is also made of white technical porcelain and has a length of 15 mm and a diameter of 10 mm and a rough ball area with a radius of curvature of 10 mm.
b. The sample volume shall be 10 mm3 or such volume as is suitable for alternative equipment. The solids are tested dry and prepared as follows:
1. the powder shall be sifted through a sieve with a mesh size of 0,5 mm; any portion passing through the sieve shall be used for testing;
2. pressed, cast or otherwise compacted substances are crushed into small pieces and sown; For the test of a substance, a sieve with a particle size of less than 0,5 mm shall be used.
Substances supplied in paste form shall be tested, preferably in a dry state. If it is not possible to prepare the substance in a dry state, the paste shall be tested after removal of the maximum possible amount of diluent, in the form of a 0,5 mm thick strip, 2 mm wide and 10 mm long prepared in forming form.
c. The porcelain pin shall be attached to the sample tested and loaded. When performing the test, the striations in the porcelain plate shall be transverse to the direction of movement. Care must be taken to ensure that the pin remains on the sample, that sufficient quantity of the sample remains under the pin and that the plate moves correctly under the pin. For grazing agents, a 0,5 mm gauge with a hole of 2 x 10 mm is used to apply the substance to the plate. The porcelain plate shall be moved under a porcelain pin along a 10 mm track back and forth in 0,44 seconds. Each part of the plate surface and pin shall be used only once; 2 ends of each pin are used for 2 tests and each of the 2 sides of the plate are used for 3 tests.
A series of 6 tests shall be carried out with a load of 360 N. If a positive result is obtained during these 6 tests, a further series of 6 tests with a load of 120 N shall be carried out. For other devices, the sample shall be compared with the selected reference substance using the specified procedure. 5)
d. The result is considered positive if the explosion is recorded in any test. The manifestation of an explosion is bang, crackle, spark or flame.
Figure 1
Heat sensitivity test device (all dimensions in mm)
Fig. 1 and Steel tube and accessories
Fig. 1 b Heating and protective equipment
(1) tube
(2) threaded ring;
thread for low friction
(3) aperture of diameter a = 2,0 or 6,0 mm
(4) a matrix with an aperture of b = 10 mm
(5) Bevelled edge
(6) 2 flat surfaces for key 41
(7) 2 flat surfaces for key 36
(8) shrapnel-resistant protective cover
(9) 2 tube-carrying bars
(10) Pipe assembled
(11) Position of the rear burner, other burners visible
(12) ignition burner
Figure 2
Heat sensitivity test
Examples of pipe rupture
It's not an explosion.
It's not an explosion.
Explosion
Explosion
Explosion
Explosion
Figure 3
Calibration of heating speed for thermal sensitivity test
Temperature-to-time curve for heating dibutyl phthalate (27 cm3) in closed tube (screen 1,5 mm) at flow rate of propane 3,2 l.min-1. The temperature shall be measured by a chromelalumel thermocouple sheathed with stainless steel with a casing diameter of 1 mm, centrally located 43 mm below the pipe edge. The heating rate between 135 ° C and 285 ° C shall be between 185 and 215 K.min-1.
Figure 4
Instrument for impact sensitivity test (all dimensions in mm)
Fig. 4a Falling hammer, front and side overall view
Fig. 4b Hammer, bottom
(1) Base plate 450x450x60
(2) Steel-cast iron block 230x250x200
(3) Anvil, diameter 100x70
(4) Column
(5) medium beam
(6) two guide bars
(7) Toothed rod
(8) Scale
(9) Hammer
(10) detention and release devices
(11) Centre sleeve
(12) interchangeable, 26 × 26 diameter
(13) centre ring with holes
(14) Test preparation
Fig. 4c Equipment for test sensitivity of powder and pastes against mechanical shock stimulus
(1) Steel rollers
(2) guide housing for steel rollers
(3) centre ring with holes
(a) vertical cut
(b) projection
Fig. 4d Equipment for the test of sensitivity of liquid to mechanical shock stimulus
(4) Rubber ring
(5) Liquid (40 mm3)
(6) Space without liquid
Fig. 4e Hammer (5 kg weight)
(1) clamping pin
(2) Position mark
(3) guide grooves
(4) Strike point
(5) locking device
Figure 5
A friction sensitivity test apparatus
Fig. 5a Friction apparatus; side and ground view
Fig. 5b Initial position of roller on sample
(1) Steel base
(2) Moving sleigh
(3) porcelain plate 25 × 25 × 5 mm, mounted on sleigh
(4) fixed porcelain pin, diameter 10 mm, length 15 mm
(5) Test sample, 10 mm3
(6) pin holder
(7) load arm
(8) Balancing weights
(9) Switch
(10) A sling adjustment wheel
(11) direction to electric motor
1) Paragraph 2 (8) (a) of Act No. 157 / 1998 Coll., on Chemicals and Chemical Products and amending certain other laws.
2) Article 2 (1) of Act No. 157 / 1998 Coll.
3) Article 2 (2) of Act No. 157 / 1998 Coll.
4) E.g. Recommendations on the Transport of Dangerous Goods, Manual of Tests and Criteria, United Nations, 1995, Test 1 (a), 2 (a): UN Gap Test; 1 (c) (i), 2 (c) (i): Time / pressure test. (Recommendations for the transport of dangerous goods. Manual for tests and criteria, United Nations, 1995, test 1 (a), 2 (a): UN gap test; 1 (c) (i), 2 (c) (i): Time / pressure test).
5) Method up-and-down.
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Regulation Information
| Citation | Decree of the Czech Mining Authority No. 316 / 1998 Coll., laying down a method for detection of explosives of chemicals and chemical preparations |
|---|---|
| Regulation Type | Order |
| Author | - |
| Collection | Code of Laws |
| Date of Promulgation | 31.12.1998 |
|---|---|
| Effective from | 01.01.1999 |
| Effective until | - |
| Status | Valid |
The regulation text is for informational purposes only.
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