Smoke Toxicity Test Equipment (Squirrel Cage Method)

The GB/T 20285 Material Smoke Toxicity Test Apparatus (Mouse Cage Method) is a specialized testing system developed in accordance with GB/T 20285-2006 for evaluating the toxicity hazards of smoke generated by building materials during combustion. The apparatus is primarily used to assess the biological toxicity of smoke under stable smoke-generation conditions and serves as an important basis for determining the combustion performance classification of B- and C-grade composite (sandwich) building materials. By combining controlled thermal decomposition with animal exposure testing, the system provides a scientific and reliable method for fire safety evaluation of construction materials.

Application

The apparatus is widely applied in fire safety research, material performance evaluation, and regulatory compliance testing. Typical applications include:

Smoke toxicity assessment of building and construction materials

Combustion toxicity evaluation of composite (sandwich) panels

Fire performance classification testing for interior decoration materials

Safety evaluation of insulation materials and polymer-based products

Toxicological smoke studies in fire research institutes

Type testing and routine inspection in third-party testing laboratories

Standards

The test apparatus complies with the following national and international standards:

(1) GB/T 20285-2006 – Classification for Toxic Hazard of Smoke Generated by Materials

(2) ISO 19700:2006 – Controlled Equivalence Ratio Method for the Determination of Hazardous Components of Fire Effluents

(3) DIN 53436 – Testing of Thermal Decomposition Products of Materials under Ventilated Conditions and Their Toxicological Evaluation

Parameters

Features

Designed specifically according to GB/T 20285-2006 for smoke toxicity hazard classification of materials.

Ring furnace adopts an energy-saving full-fiber furnace tube structure with stable thermal performance.

High-precision temperature control system ensures furnace temperature meets the requirements of Chapter 7 of GB/T 20285.

Stepper-motor-driven furnace displacement system provides low noise, high accuracy, and flexible speed selection.

Quartz tube and joints are precision ground and paired during processing to ensure excellent sealing performance.

Waste gases generated during testing are directly discharged into the ventilation duct through plastic hoses, preventing smoke leakage in the working area.

Transparent exposure chamber allows visual observation of test animals during exposure.

Mouse rotating cages are designed to rotate freely, preventing fixed postures and reducing the risk of mechanical injury.

Integrated carrier gas and dilution gas supply system ensures stable smoke concentration control.

Computer-based control system enables high automation and real-time monitoring of test parameters.

Accessories

(1) Ring furnace heating system

(2) Quartz tube

(3) Quartz boat

(4) Smoke collection and distribution assembly

(5) Transparent organic glass exposure chamber

(6) Mouse rotating cages

(7) Temperature control and furnace displacement system

(8) Carrier and dilution gas supply components

(9) Computer control software system

Test Procedures

Specimen Installation

Prepared specimens are placed into the quartz boat and positioned at the specified location inside the quartz tube.

Animal Placement

Experimental mice are placed into the aluminum rotating cages, ensuring free rotation without fixed stationary points to avoid injury or restricted movement.

System Startup

The industrial computer and control software are started, and a preset test program is selected.

The ring furnace is heated to the required temperature, and once stable, the furnace begins uniform scanning movement to heat the specimen.

Exposure and Monitoring

Smoke is diluted by carrier air and introduced into the exposure chamber, where mice are exposed for 30 minutes.

The software displays temperature curves, airflow rate, and furnace displacement in real time while animal behavior is observed.

Data Collection

Smoke concentration and related parameters are automatically recorded.

After the test, the system generates and prints test data, including time-temperature curves and mouse survival information.

Maintenance Information

Regular inspection of the quartz tube, sealing joints, and gas pipelines is recommended to maintain proper sealing and safe operation. The temperature control system and furnace displacement mechanism should be periodically checked to ensure accuracy and smooth movement. After testing, the exposure chamber and quartz components should be cleaned to prevent residue accumulation. Software data should be backed up regularly, and sensor calibration should follow laboratory quality management requirements.

Conclusion

The GB/T 20285 Material Smoke Toxicity Test Apparatus (Mouse Cage Method) provides a standardized and reliable solution for evaluating the toxic hazards of smoke generated by building materials during combustion. Through controlled smoke generation, precise temperature regulation, and biological exposure testing, the system meets the requirements of GB/T 20285. ISO 19700. and DIN 53436. It is well suited for fire safety research, material classification, and regulatory compliance testing.

FAQ

1. What is the primary purpose of this smoke toxicity test apparatus?

The apparatus is used to evaluate the toxic hazard level of smoke generated by building materials during combustion. By simulating stable smoke-generation conditions and combining them with animal exposure tests, the system assesses the biological toxicity of combustion products. The results are an important basis for determining the combustion performance classification of B- and C-grade composite building materials in accordance with GB/T 20285-2006.

2. How is smoke toxicity evaluated during the test?

Smoke toxicity is evaluated by exposing laboratory mice to diluted combustion smoke under controlled conditions. The smoke generated by the heated specimen is transported into a sealed exposure chamber, where mice are exposed for a fixed duration of 30 minutes. During this period, mouse activity and survival are monitored and recorded by the system. The collected data are used to determine the smoke toxicity hazard classification defined in the standard.

3. What role does the ring furnace displacement system play?

The ring furnace displacement system enables uniform and controlled heating of the specimen through constant-speed scanning. Driven by a stepper motor, the system provides precise movement control with selectable speeds, ensuring repeatable thermal exposure conditions and stable smoke generation throughout the test.

4. Is the system fully computer controlled?

Yes. The apparatus is operated and controlled by computer software consisting of multiple functional modules, including parameter setting, temperature display, mouse observation, data storage, and test result output. Test reports and graphs can be printed directly after completion.