Yttrium

Flammability

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

substances / mixtures which in contact with water emit flammable gases

Type of information:

experimental study

Adequacy of study:

key study

Study period:

14 March 2017 - 9 June 2017

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

UN Manual of Tests and Criteria: Test N.5 (Test method for substances which in contact with water emit flammable gases)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Key result

Test procedure:

step 1

step 2

step 3

step 4

Identity of evolved gas:

not applicable as no gas evolved

Remarks:

Neither release of gas nor ignition was observed.

Remarks on result:

no reaction with water observed

Remarks:

Neither release of gas nor ignition was observed.

- Under the experimental conditions of Step 1, Step 2, Step 3 and Step 4, neither release of gas nor ignition was observed.

- In step 4, the test item was used as supplied since the percentage of particles with particle diameter < 500 µm was 99.9%.

Interpretation of results:

not classified based on GHS criteria

Conclusions:

In the UN 5 test performed with yttrium metal in powder form, neither release of gas nor ignition was observed in Step 1, 2, 3 and 4 of the test procedure. Consequently, the test item was not classified in Division 4.3 and thus was not assigned to any packing group. According to EC No. 1272/2008 (CLP Regulation), the test item does not need to be classified for this physical hazard.

Reference 2

Endpoint:

flammable solids

Type of information:

experimental study

Adequacy of study:

key study

Study period:

3 March 2017 - 9 June 2017

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

UN Manual of Tests and Criteria: Test N.1 (Test method for readily combustible solids)

Version / remarks:

Sixth revised edition (2015)

Deviations:

yes

Remarks:

The test item was formed into an unbroken strip of about 130 mm long instead of 250 mm long as it was not possible to break it in small pieces. This deviation was not considered to have affected the quality or the interpretation of the results obtained.

GLP compliance:

yes (incl. QA statement)

Key result

Test procedure:

burning rate test: preliminary screening test

Remarks on result:

other: substance does not ignite and propagate combustion either by burning with flame or smouldering along 200 mm of the powder train within the 20 minutes test period

During the preliminary test (both assays), the test item became incandescent but neither ignition nor propagation was observed.

Taking into account the results obtained during the preliminary test, no main test was performed.

Interpretation of results:

not classified based on GHS criteria

Conclusions:

The preliminary screening test was performed for the determination of the flammability of the test item (yttrium metal pellets).
No propagation of combustion of the test item was observed during the preliminary test (both assays). Consequently, and according to the guidelines, performance of the burning rate test was not required. Based on the results obtained, the test item does not need to be classified as a flammable solid of Division 4.1 and thus is not assigned to any packing group, under the experimental conditions used. According to EC No. 1272/2008 (CLP), the test item is not classified.

Reference 3

Endpoint:

flammable solids

Type of information:

experimental study

Adequacy of study:

key study

Study period:

21 February 2017 - 9 June 2017

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

UN Manual of Tests and Criteria: Test N.1 (Test method for readily combustible solids)

Version / remarks:

Sixth revised edition

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Key result

Test procedure:

burning rate test: preliminary screening test

Remarks on result:

other: substance does not ignite and propagate combustion either by burning with flame or smouldering along 200 mm of the powder train within the 20 minutes test period

During the preliminary test (both assays), the test item reddened, some sparks were observed during the application of the flame, but neither propagation nor ignition was observed.

Taking into account the results obtained during the preliminary test, no main test was performed.

Interpretation of results:

not classified based on GHS criteria

Conclusions:

The preliminary screening test was performed for the determination of the flammability of the test item (yttrium metal powder form).
No propagation of combustion of the test item was observed during the preliminary test (both assays). Consequently, and according to the guidelines, performance of the burning rate test was not required. Based on the results obtained, the test item does not need to be classified as a flammable solid of Division 4.1 and thus is not assigned to any packing group, under the experimental conditions used. According to EC No. 1272/2008 (CLP), the test item is not classified.

Reference 4

Endpoint:

pyrophoric solids

Data waiving:

study scientifically not necessary / other information available

Justification for data waiving:

the study does not need to be conducted because the substance is known to be stable in contact with air at room temperature for prolonged periods of time (days) and hence, the classification procedure does not need to be applied

Reference 5

Endpoint:

self-heating substances / mixtures

Data waiving:

study scientifically not necessary / other information available

Justification for data waiving:

other:

Description of key information

Flammability: Based on the experimental tests performed using the pellet (Demangel, 2017, Klimisch score 1) and powder (Demangel, 2017, Klimisch score 1) forms of yttrium metal according to the guideline UN N.1 in compliance with GLP, yttrium metal was not determined to be a flammable solid. However,

it was decided to classify powder forms of yttrium metal as Flammable Solid Category 2, based on experience with the daily handling and use, and taking into account the precautionary principle.

Flammability in contact with water: In an experimental study (Demangel, 2017, Klimisch score 1) performed with yttrium metal in powder form according to the guideline UN N.5 in compliance with GLP neither release of gas nor ignition was observed. Based on this result, it can be concluded that yttrium metal does not fulfill the conditions to be classified in Division 4.3 and thus was not assigned to any packing group.

Self-heating: Based on the experimental test performed (Demangel, 2017, Klimisch score 1) according to EU test method A.16 (relative self-ignition temperature of solids), the temperature of the test item did not deviate from the temperature of the oven up to an oven temperature of 400°C. Based on this observation, the substance can safely be concluded to be not self-heating.

Pyrophoricity: Based on experience when yttrium metal has been in contact with air at room temperature for prolonged periods of time (days), during which the substance did not exhibit pyrophoric properties, it can be concluded that yttrium metal is not pyrophoric.

Key value for chemical safety assessment

Flammability:

flammable

Additional information

Although a UN N1 test performed with a powder form of yttrium metal did not result in classification under the CLP Regulation, it was decided to classify powder forms of yttrium metal as Flammable Solid Category 2, based on experience with the daily handling and use, and taking into account the precautionary principle.

Justification for classification or non-classification

Based on experimental studies (Demangel, 2017, Klimisch score 1), yttrium metal should not be classified as substance which in contact with water emits flammable gases or as a self-heating substance based on the UN N.5 and EU A.16 method respectively. Furthermore, based on experience, yttrium metal should not be classified as pyrophoric.

Although a UN N1 test performed with a powder form of yttrium metal did not result in classification under the CLP Regulation, it was decided to classify powder forms of yttrium metal as Flammable Solid Category 2, based on experience with the daily handling and use, and taking into account the precautionary principle.