Vertical Flammability Tester

The Vertical Flammability Tester evaluates textile flammability by measuring the flame propagation speed on vertically positioned samples, making it ideal for children’s wear, pajamas, and safety fabrics. It uses a controlled flame ignition system and records afterburning, smoldering times, and flame height. Designed for precision, it follows 16CFR1615, 1616 standards, allowing testing of finished garments, seams, and decorative fabrics. The instrument ensures compliance with federal and international flammability regulations, enabling manufacturers to assess and improve fabric safety effectively.

Experimental Parameters

• Sample size: 80 mm × 300 mm
• Ignition mode: automatic
• Ignition time: 12 seconds
• Ignition device diameter: Φ11 mm
• Afterburning and smoldering time: 0–999.9 seconds
• Flame height: 40 mm
• Gas type: propane, butane, or liquefied petroleum gas

Test principle

This tester ignites the sample at its lowest point and measures flame speed using the vertical method. During testing, the sample stands vertically while a flame with a 38 mm length burns the sample for 3 seconds. Operators determine the flame-burning speed by measuring the distance from the sample’s bottom to the point where the creased sample tears under a specified force.

Sample Preparation and Sampling

• Test sample: Cut cloth pieces measuring 8.9 × 25.4 cm. Include seams or decorations if present, or use finished garments as they are.
• Sampling: Follow 16CFR1615 and 1616. Cut 5 test samples from cloth pieces, seams, decorations, or finished garments.
• Each sample must measure 254 ± 3 mm in length and 89 ± 3 mm in width. Take 2–3 samples along the length and 2–3 along the width to reach 5 total samples per tested material.
• Fabrics for children’s pajamas require testing in their original state and after 50 washes. Non-flame-retardant fabrics without special functions only need testing in their original state. If these fabrics meet federal standards initially, they pass flammability requirements after 50 washes.

Test Procedure

• Turn off the exhaust fan. Open the gas supply and adjust the needle valve so the burner flame measures 38 mm. Close the test chamber door for at least 5 minutes. Dim the room light and adjust the flame to 38 ± 2 mm from the burner’s upper end to the visible flame top.
• Hang the sample on the test chamber rod immediately after removing it from the dryer, within 30 seconds. Position the flame under the sample’s bottom center.
• Ignite the sample for 3.0 ± 0.2 seconds and move the burner away to stop ignition.
• Open the fume hood and exhaust smoke completely. Avoid inhaling fumes and wear proper breathing protection.
• Carefully remove the hot sample clamp and sample. Press a wrinkle along the sample’s length starting from the highest carbonization point.
• Insert a dome hook 6.4 ± 20 mm from the sample’s bottom on the non-carbonized side and hang a heavy hammer on it.
• Lift the other sample end gently until the hammer just leaves the surface. This action tears the burned sample.
• Use a ruler to measure the carbonization length from the torn end to the ignition point and record it.
• Repeat steps 2–8 for all 5 samples.
• Report the average carbonization length of the 5 samples and the maximum carbonization length for each sample.

Why Choose Vertical Flammability Tester?

The Vertical Flammability Tester is essential for textile manufacturers and quality labs aiming to ensure flame safety compliance. It precisely ignites samples at their lowest point and measures flame speed, afterburning, and carbonization length. The instrument accommodates finished garments, seams, and decorative fabrics, allowing testing in real-world conditions, including after multiple washes for children’s sleepwear. It supports propane, butane, or liquefied petroleum gas and features automatic ignition, adjustable flame, and strict sample positioning, ensuring reproducible and reliable results. The tester follows international standards such as 16CFR1615/1616, providing manufacturers with confidence that fabrics meet regulatory requirements while maintaining operational safety and testing efficiency.