1-nitroguanidine

Explosiveness

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

explosive properties of explosives

Type of information:

experimental study

Adequacy of study:

supporting study

Study period:

September 1997 - March 1998

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

test procedure in accordance with national standard methods with acceptable restrictions

Qualifier:

equivalent or similar to guideline

Guideline:

EU Method A.14 (Explosive properties)

Deviations:

yes

Remarks:

slightly other test methods, no thermal sensitivity

Principles of method if other than guideline:

The principles of the test methods including their deviations to the guideline are described in detail in the field "any other information on materials and methods".

GLP compliance:

not specified

Parameter:

other: More sensitive to shock than m-dinitrobenzene

Remarks on result:

not measured/tested

Remarks:

shock sensitivity measured with different test method

Parameter:

other: More sensitive to friction than m-dinitrobenzene

Remarks on result:

not measured/tested

Remarks:

friction sensitivity measured with different test method

Parameter:

other: Explosive under influence of flame

Remarks on result:

not measured/tested

Parameter:

other: Explosive (not specified)

Remarks on result:

negative (not further specified)

Mechanical sensitivity (friction):

No scorch marks on the clay plate or the wooden lag and changes in the substance were observed in all six tests.

Mechanical sensitivity (shock):

No scorch marks on the driving band or the underlayment and no change of the substance at any sample were observed.

Interpretation of results:

other: nitroguanide is not sensitive to shock and friction

Conclusions:

The two tests for mechanical sensitivity to friction and shock showed no explosive properties of nitroguanidine.

Executive summary:

The study was conducted slightly different from guideline A.14 and investigated the mechanical sensitivity to friction and shock of nitroguanidine. The thermal sensivity was not investigated. The results show no explosive properties of nitroguanide as the test substance is not sensitive to shock and friction.

Reference 2

Endpoint:

explosive properties of explosives

Type of information:

experimental study

Adequacy of study:

key study

Study period:

1961

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

study well documented, meets generally accepted scientific principles, acceptable for assessment

Qualifier:

no guideline followed

Principles of method if other than guideline:

Testing method for sensitivity of detonation (detonator cap)
A detonator cap is used in a lead block according to Tauzl. A nitropenta detonator cap no 8 with copper hull, outside diameter of 6.85 mm and 45 mm lenghth is used. The detonator cap includes 0.5 g nitropenta with 10% wax which is tampered with a pressure of 400 kg/cm² and 0.2 Tetryl and for charge purpose 0.5 g of mercury fulminate which is tampered with 400 kg/cm² as well.
Solid explosives are formed to test pieces of 11 ml volume wrapped in til foil and put into the testing apparatus used for the test in the lead block according to Tauzl.
The lead block shall have a temperature of 20 +-5 °C during the test. The detonator cap with its initiator is put to the bottom of the lead block using a wooden stick which is marked as to know when the bottom is reached. After the stick is removed the remaining hollow space is filled with quartz sand (which has been filtered through a sieve with 0.5 mm mesh size).
After detonation the generated hollow space within the lead block is measured using water. A 500 ml measuring cylinder with marks every 2 ml and ring marks every 10 ml is used. The test has to be conducted twice.

The second part of the test is conducted in a steel tube with a diameter of 1 inch which is closed on both ends. An identical nitropentan detonator cap no 8 is used. The steel tube has an outer diameter of 33.3 mm, wall thickness of 4 mm and 300 mm length and is welded on the ground. The open end has a winding for a cap. Latter has a borehole with 7.5 mm diameter. Powdery substances are filled in, if necessary by pushing the steel tube carefully frequently. Pieces of the steel tube have to be collected completely as far as possible. If necessary, the test has to repeated.

GLP compliance:

not specified

Specific details on test material used for the study:

Test substance supplier not specified

Parameter:

other: More sensitive to shock than m-dinitrobenzene

Remarks on result:

not measured/tested

Parameter:

other: More sensitive to friction than m-dinitrobenzene

Remarks on result:

not measured/tested

Parameter:

other: Explosive under influence of flame

Remarks on result:

not measured/tested

Key result

Parameter:

other: Explosive (not specified)

Remarks on result:

positive (not further specified)

Remarks:

in test of sensitivity of detonation in a nitropenta detonator cap

The 11 ml volume of test substance in the detonator cap amount to 7.5 g.

In the test in the lead block according to Trauzl the hollow space after detonation was determined to be 305 ml per dekagramm.

The result of the test in a steel tube (1 inch diameter) showed a transfer of the detonation.

Interpretation of results:

Division 1.1 (substances, mixtures and articles which have a mass explosion hazard) based on GHS criteria

Conclusions:

The test substance has to be considered as explosive as the test for sensitivity in a detonator cap showed positive results.

Executive summary:

The test was conducted according to the requirements of a method developed by the German Federal Institute for Material Testing (BAM). It was investigated whether the test substance is sensitive for detonation in a detonator cap. Therefore, a test in a lead block according to Trauzl and a test in a steel tube (1 inch diameter) was conducted. The detonation in the lead resulted in a hollow space within this block a 305 ml/dekagramm. The detonation in the steel tube (1 inch diameter) showed that the test substance transfers the detonation. Therefore, nitroguanidine is considered to be explosive in the means of sensitive for detonation in a detonator cap.

Reference 3

Endpoint:

explosive properties of explosives

Type of information:

experimental study

Adequacy of study:

key study

Study period:

1961

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

study well documented, meets generally accepted scientific principles, acceptable for assessment

Qualifier:

equivalent or similar to guideline

Guideline:

EU Method A.14 (Explosive properties)

Deviations:

yes

Remarks:

Thermal sensitivity: Combined burner consumption is nearly doubled (6.8 l/m); tamping force of substance in steel tube is only described as 'tamper with slight force'; substance is filled at once into the tube; maximum heating is not limited

GLP compliance:

not specified

Specific details on test material used for the study:

Test substance supplier not specified

Parameter:

other: More sensitive to shock than m-dinitrobenzene

Remarks on result:

other: no data

Parameter:

other: More sensitive to friction than m-dinitrobenzene

Remarks on result:

other: no data

Key result

Parameter:

other: Explosive under influence of flame

Remarks on result:

negative (not further specified)

Key result

Parameter:

other: Explosive (not specified)

Remarks on result:

negative (not further specified)

Thermal sensitivity: no explosion was observed, even though the diameter of the orifice plate was 1.0 mm.

Mechanical sensitivity (shock): no explosion observed even though the energy used was 50 J instead of 40 J

Mechanical sensitivity (friction): no explosion observed at 36 kN

Interpretation of results:

GHS criteria not met

Conclusions:

All three tests regarding thermal and mechanical sensitivity indicated no explosive properties of nitroguanidine.

Executive summary:

The test results and the appropriate methods were published in the same source but not simultaneously. However, within the publications, it is explicitly refered to that these methods were developed and the appropriate results are shown in a separate publication.

Different substances were tested for various parameters with regard to explosive properties. The authors from the Federal Instiute for Material Testing developed methods to describe explosive properties by means of characteristics. Nitroguanidine was tested for thermal and mechanical sensitivity (shock and friction) and showed no explosive properties in each of the tests.

Description of key information

There are two studies available investigating the mechanical sensitivity whereas only one study investigates the thermal

sensitivity. An additional study is available investigating the sensitivity of nitroguanidine for detonation in a detonator cap.

Key value for chemical safety assessment

Explosiveness:

explosive

Additional information

The key study is chosen because it includes tests regarding the mechanical as well as the thermal sensibility. A supporting study is chosen for the determination, if nitroguanidine is considered to be explosive or not. This supporting study investigates a special usage in detonator caps.

The results of two studies for mechanical sensitivity are consistent indicating no explosive properties (no explosion in friction until 36 kg and no explosion in shock until 5 kgm). The thermal sensitivity investigated in one study showed no explosive properties as well, though the test was conducted with a diameter of 1 mm in the orifice plate instead of 2 mm as requested in the guideline. Therefore all three tests required for this endpoint according to guideline A.14 showed negative results.

The third test investigating the sensitivity of nitroguanidine for detonation in a detonator cap is not obligatory within this endpoint. Nevertheless, there is information available which is required within the context of classification and labelling. The test for sensitivity for detonation in a detonator cap showed positive results. The equivalent amount of nitroguanidine in the detonator cap for 11 ml is 7.5 g. The test in the lead block according to Trauzl resulted in a hollow space due to the detonation of 305 ml/dekagramm. The test in a steel tube (1 inch diameter) showed that nitroguanidine transfers the detonation.

Therefore it is concluded that nitroguanidine is explosive.

Justification for classification or non-classification

Although the tests stated in guideline A.14 showed all negative results, an additional test with regard to sensivity for detonation in a detonator cap indicated positive results. As the latter tests are part of the evaluation of the explosive properties of a substance in context of classification and labelling, it is therefore concluded, that nitroguanidine is to be classified as explosive.