1. Mechanical Impact Resistance
This is the core indicator for measuring the safety of laminated glass, to see if fragments fly or penetrate when it is impacted.
Drop Ball Impact Test
Method: Use a 1040g steel ball from different heights (depending on the type and thickness of the glass, such as 1m, 1.5m, 2m, 3m...) Free fall strikes the center of the glass.
Qualification standard: After impact, if the glass breaks, the middle layer must be torn apart and the fragments must not have an area larger than 75px² falling off the middle layer. The main purpose is to test the resistance to penetration and the adhesion of fragments.
Shot Bag Impact Test
Method: Use a 45kg shotgun bag (leather sandbag) to strike the glass sample through a pendulum or drop device.
Qualification standard: After impact, the test bag must not penetrate the sample. This test simulates a human impact and is a mandatory test for safety glass used in buildings.
2. Durability/Environmental Stability Tests
Simulate the environmental conditions that laminated glass may encounter during long-term use to test its service life.
Heat Resistance test:
Method: Keep the sample in an oven at (100±2)℃ for 2 hours.
Qualification standard: After cooling, bubbles or other defects are allowed at the edge of the glass, but no bubbles or delamination that affect the view are permitted within 13mm from the edge. Check whether the middle layer will decompose and produce bubbles at high temperatures.
Resistance to Humidity test:
Method: The samples were placed in an environment with a humidity greater than 95% and a temperature of (50±2)℃ for 336 hours (14 days).
Qualification standard: After the test, the glass must not have any delamination that exceeds 13mm from the edge or 1/2 of the bubble diameter. Check whether the middle layer will lose its adhesive force due to water absorption in a humid environment.
Resistance to Radiation test:
Method: Continuously irradiate the sample with an ultraviolet radiator.
Qualification standard: After the test, the sample shall not produce significant bubbles, fogging, delamination or other phenomena, and the decrease rate of visible light transmittance shall not exceed 5%. Check whether the intermediate layer material will age or yellow under long-term exposure to sunlight.
3. Optical Performance and Visual Quality
Transmittance/refraction distortion: Check if the glass has obvious optical distortion that affects the line of sight.
Bubbles, impurities, scratches and other defects: The standard clearly stipulates the number, size and spacing of defects allowed for different grades of glass.
4. Other specialized tests
Wind pressure resistance performance: For curtain wall glass, pressure tests should be conducted based on wind load design.
Sound insulation performance: Measure its weighted sound insulation (Rw) to evaluate the sound insulation effect.
Anti-theft/bulletproof/anti-explosion performance: There are stricter dedicated standards (such as GA 165-2016 "Bulletproof Transparent Materials", GB 17840-1999 "Bulletproof Glass"), and the testing methods include multiple impacts, shooting with firearms of different calibers, etc.
Standards for different application fields
Automotive field: Adhere to GB 9656-2021 "Safety Technical Specification for Motor Vehicle Glass" (Chinese standard for automotive safety Glass). This standard mainly focuses on visible light transmittance, optical distortion, impact resistance, and the impact of human head models, etc., to ensure driving safety.
In the aerospace field, there are extremely strict standards, such as bird impact resistance tests and pressure variation tests.
Anti-theft and bulletproof field: Comply with relevant standards of the Ministry of Public Security (such as GA 165-2016, etc.).
