The test is designed to determine the ability of a substance to undergo oxidative self-heating by exposing it to air at elevated temperatures in a wire mesh cube. The Basket Self-Heating Test is a laboratory test used to assess the self-heating properties of solid materials, particularly those prone to spontaneous combustion. It is commonly employed to evaluate the tendency of materials to generate heat when exposed to air or oxygen.
In this test, a sample of the material, typically in the form of pellets, particles, or granules, is placed inside a wire mesh basket or container. The basket is then positioned within an oven or enclosed chamber set to a specified temperature. The sample’s temperature is monitored continuously or at regular intervals over an extended period.
Testing Principle and Methodology
The sample basket is filled to the top with the test material. The sample basket is then housed in covers and placed in the center of the oven at the required test temperature for up to 24 hours or until exothermic decomposition is observed. The sample and oven temperatures are continually monitored and logged with two thermocouples, one placed in the center of the sample and the other between the sample container and the oven wall. A positive result is obtained if spontaneous ignition occurs or if the temperature of the sample exceeds the oven temperature by 60 °C. Typically, we require about 1 kilogram worth of the material but may use less or more depending on the density of the material. UN Transport of Dangerous Goods Manual of Tests and Criteria recommends the sample to be tested in its commercial form or as received. In case of uncertainty on how to perform the testing please contact Prime Process Safety Center for guidance.
Basket Self-Heating Instrument manufactured by Carbolite Gero, UK
Typical Self-Heating Graph
Applicable Standard
The Basket Self-Heating test is conducted in accordance with the UN/DoT Standard for Transport of Dangerous Goods, Manual of Tests and Criteria, and EN15188: Determination of the spontaneous ignition behaviour of dust accumulations.
Data Interpretation
A substance is classified as a self-heating substance of UN Class 4, Division 4.2 if a positive test result is observed in a 100 mm basket at 140°C. A positive result is defined as a sample temperature rise of 60°C (or more) above the oven temperature during a 24-hour period. From this point the following packing groups are then assigned to the sample:
| Packaging Group II | Assigned to any substance which gives a positive test result in a 25mm basket at 140°C. |
| Packaging Group III | Assigned to any substance which:
a.      gives a positive test result in a 100mm basket at 140°C and a positive test result in a 100 mm basket at 100°C b.      gives a positive test result in a 100mm basket at 140°C and a negative test result in a 100 mm basket at 120°C and is to be transported in packages of more than 3 m3 volume c.       gives a positive test result in a 100mm basket at 140°C and a negative test result in a 100mm basket at 100°C and is to be transported in packages of more than 450L volume |
| Not Division 4.2 | Assigned to any substance which:
a.      gives a negative test result in a 100mm basket at 140°C. b.      gives a positive test result in a 100mm basket at 140°C and a negative test result in a 100 mm basket at 120°C and is to be transported in packages of less than 3m3 volume c.       gives a positive test result in a 100mm basket at 140°C and a negative test result in a 100mm basket at 100°C and is to be transported in packages of less than 450L volume |
When to perform Basket Self-Heating Test
Self-Heating test is recommended whenever a new material is to be transported in bulk in certain quantities. It is applied to products which are subjected to elevated temperatures in an air stream. This test is designed to determine the relative self-heating onset temperature of a material in a hot air-stream. It is applied to products which are subjected to elevated temperatures in an air stream. The Basket Self-Heating Test helps in determining the material’s susceptibility to spontaneous heating and subsequent combustion when exposed to specific conditions such as increased temperatures, oxygen availability, or limited ventilation.
Why work with Prime Process Safety Center
- Prime Process Safety Center is a leader in process safety testing services with very experienced laboratory personnel. At Prime Process Safety Center our goal is to provide accurate, reliable and defensible data that meets industry and regulatory standards. We understand the need for the quality of your data, and we work assiduously to achieve just that.
- We are knowledgeable and experienced in performing Basket Self-Heating Tests, ensuring accurate and reliable results.
- We have state-of-the-art basket self-heating testing equipment, providing precise and sensitive measurements.
- We follow strict testing protocols and quality control measures to ensure consistent and reliable test results.
- Our team can interpret and analyze the data obtained from the tests, providing valuable insights and recommendations for your specific application or research.
FAQs
What is the Basket Self-Heating Test?
Answer: The Basket Self-Heating Test is a laboratory procedure used to assess materials’ propensity for self-heating and spontaneous combustion by subjecting samples to elevated temperatures in a controlled environment.
How does the Basket Self-Heating Test work?
Answer: The test involves placing a sample of the material, typically in pellet or granular form, inside a wire mesh basket or container. This basket is then exposed to controlled elevated temperatures, and the sample’s temperature changes are monitored over time.
Why is the Basket Self-Heating Test conducted?
Answer: The test is conducted to evaluate materials’ susceptibility to self-heating and spontaneous combustion under specified conditions. It helps in assessing potential fire hazards associated with certain materials.
What types of materials are commonly subjected to the Basket Self-Heating Test?
Answer: Materials prone to self-heating and spontaneous combustion, such as certain chemicals, organic substances, and combustible solids, are often tested using this method.
What parameters are monitored during the Basket Self-Heating Test?
Answer: The test monitors the sample’s temperature changes over time to observe any self-heating tendencies, particularly when exposed to increased temperatures.
How long does the Basket Self-Heating Test typically last?
Answer: The duration of the test can vary based on the material being tested and the specified testing conditions. It may range from several hours to multiple days.
Is the Basket Self-Heating Test a standard test method?
Answer: While variations in testing procedures may exist, the Basket Self-Heating Test is a recognized method used in various industries to evaluate self-heating tendencies of materials.
What safety measures are considered during the Basket Self-Heating Test?
Answer: Safety protocols are observed to prevent potential fire hazards during the test. Adequate ventilation and proper handling of materials susceptible to spontaneous heating are crucial.
What does a positive result in the Basket Self-Heating Test indicate?
Answer: A positive result suggests that the material has a tendency to generate heat and could pose a risk of spontaneous combustion under certain conditions.
How is the data from the Basket Self-Heating Test utilized in industries?
Answer: Industries use test results to assess fire risks associated with materials, develop preventive measures, and establish safe storage, handling, and transportation practices.