Hydrogen peroxide-urea

Explosiveness

Link to relevant study record(s)

Reference

Endpoint:

explosive properties of explosives

Type of information:

experimental study

Adequacy of study:

key study

Study period:

from 2012-10-18 to 2012-12-05

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study with acceptable restrictions

Qualifier:

according to guideline

Guideline:

UN Manual of Tests and Criteria: Part I: Classification procedures, test methods and criteria relating to explosives of Class 1

Version / remarks:

5th edition, 2009

Deviations:

no

GLP compliance:

no

Key result

Test series:

UN Test series 2

Method:

UN Test 1 (c) (i): Time/pressure test

Parameter:

other: time (ms)

Value:

1 072

Result:

result is considered "+" (positive)

Key result

Test series:

UN Test series 2

Method:

UN Test 2 (a): UN gap test

Parameter:

fragmented length (cm)

Value:

40

Result:

result is considered "-" (negative)

Key result

Test series:

UN Test series 2

Method:

UN Test 2 (b): Koenen test

Parameter:

limiting diameter (mm)

Value:

1

Result:

negative, no explosion

Key result

Test series:

UN Test series 2

Method:

UN Test 2 (c) (i): Time/pressure test

Parameter:

other: time (ms)

Value:

720

Result:

result is considered "-" (negative)

DSC method

The determination of the heat of decomposition at a heating rate of 5 K / min gave the following result:

Table 1. Total heat of decomposition determine using the DSC method

Test No.	Weight	Melting point	Extrapolated ONSET temperature		Heat of decomposition
			Peak 1	Peak 2	Peak 1	Peak 2
1	3.96 mg	85 °C	90 °C	274 °C	967 J/g	1902 J/g
2	2.49 mg	87 °C	92 °C	236 °C	867 J/g	2174 J/g

Time/pressure Test (UN-Test 1 (c) (i) and 2 (c) (i))

After confinement in the pressure-time bomb, for pressure increase from 790 kPa to 2170 kPa times of 1072 ms, 912 ms and 720 ms were measured in three experiments.
Assessment according to UN-Test 1 (c) (i): "+" (positive)

Assessment according to UN-Test 2 (c) (i): "-" (negative)

GAP-Test. UN-Test 2 (a)

1st attempt: 379.1 g of the test item were used. The steel tube was not fragmented. No hole was punched in the detection plate. Tube length obtained: 40.0 cm Approximately 95 % of the substance were preserved.

2nd attempt: 373.5 g of the test item were used. The steel tube was not fragmented. No hole was punched in the detection plate. Tube length obtained: 40.0 cm Approximately 95 % of the substance were preserved.

Assessment according to UN-Test 2 (a): "-" (negative)

Additional tests

Koenen test (nozzle opening 1.0 mm) (UN test 1 (b) and 2 (b)): negative, no explosive

2-inch steel tube (50 g booster) (UN test A.1): complete transmission of the detonation

Interpretation of the results

According to UN Test A.1 the test item should be regarded as explosive in class 1 for classification, which is the worst case. To determine the explosiveness of the test item in details UN Test series 2 were performed and the following observations and results led to the conclusion that the test item is not an explosive in class 1.

Table 2. Logic of interpretation of the results

3	Box 5	Test series 2
3.1	Sensitivity to shock	UN Gap Test (Test 2 (a))
3.2	Sample conditions	ambient temperature
3.3	Observation	No forwarding
3.4	Result	"-", no sensitivity to shock
3.5	Heat effect including	Koenen Test (Test 2 (b))
3.6	Observation	Boundary diameter less than 1.0 mm
3.7	Result	"-", no effect on heating under confinement
3.8	Ignition effect under inclusion	Pressure / time test (test 2 (c) (i))
3.9	Observation	Times 1072 ms, 912 ms and 720 ms
3.10	Result	"-". Substance is not capable of rapid deflagration
3.11	Output	Go to Box 6
4	Box 6	Is the substance too insensitive to class 1 classification?
4.1	Result of Test Series 2	Yes
4.2	Output	Go to Box 7
5	Box 7	Not Explosive in Class 1

The results of UN Test Series 2 showed that classification of the test item in Class 1 is too insensitive. Therefore, the test item is not classified as explosive in class 1.

Interpretation of results:

GHS criteria not met

Conclusions:

The test item was determined not to be an explosive in class 1.

Executive summary:

A study perfomed according to UN Test Series 1 and 2 (5th edition, 2009) was perfomed to determined the explosive properties of the test item. In UN Test A.1 the test item showed a positiv effect on the detonation. Time/pressure test UN Test 1 (c) (i) showed positiv results as well. Further test from UN Test series 2 - GAP test, Time/pressure test and Koenen test were perfomed. All three tests showed negative results. Following the flow chart logic in the UN Guideline and based on the observations and results it was concluded that the test item is not an explosive classified in class 1.

Description of key information

Non explosive.

Key value for chemical safety assessment

Explosiveness:

non explosive

Additional information

A study perfomed according to UN Test Series 1 and 2 (5th edition, 2009) was perfomed to determined the explosive properties of the test item. In UN Test A.1 the test item showed a positiv effect on the detonation. Time/pressure test UN Test 1 (c) (i) showed positiv results as well. Further test from UN Test series 2 - GAP test, Time/pressure test and Koenen test were perfomed. All three tests showed negative results. Following the flow chart logic in the UN Guideline and based on the observations and results it was concluded that the test item is not an explosive classified in class 1.

Justification for classification or non-classification

Classification, Labelling, and Packaging Regulation (EC) No. 1272/2008

In accordance with Annex I, Section 2.1 of Regulation (EC) No 1272/2008, as amended for the tenth time in Regulation (EC) No 2017/776, and UN GHS Rev 6 (2015) the substance has to not be classified as explosive in class 1.