SIST EN 4057-302:2009

Overview

EN 4057-302:2006 is a CEN aerospace series test method that specifies how to determine the burning characteristics of cable ties used in aircraft harnesses. The standard is intended to be used together with EN 4057-100 (General test methods) and supports material selection, product qualification and regulatory compliance for electrical harness components in aerospace applications.

Key Topics

• Scope and purpose: Establishes a repeatable procedure to assess flammability behaviour of cable ties for harnesses.
• Apparatus: Test enclosure (hood or cabinet) free from air currents and a 9,5 mm Bunsen burner configured to produce a 75 mm non-luminous flame with a 25 mm blue cone.
• Calibration checks: Use a bare copper wire of (0,7 ± 0,025) mm diameter and at least 100 mm free length to set the burner so the wire melts within 4–6 s when exposed to the blue cone.
• Specimen mounting: The tail of the cable tie is trimmed to the uniform section and mounted horizontally in the test clamp.
• Exposure and observation: The burner is positioned at a (45 ± 5)° angle to the specimen; the tip of the strap is introduced into the blue cone for the specified exposure period. Record the time taken for flaming to cease after removal and note any falling burning or flaming particles.

Keywords: EN 4057-302:2006, cable ties, flammability test, aerospace harnesses, test methods, EN 4057-100

Applications

This test method provides practical value for:

• Manufacturers verifying material and component performance against flammability expectations for aerospace harness components.
• Design and quality engineers selecting cable tie materials for installation in aircraft where controlled burning behaviour is required.
• Compliance teams and test laboratories that need a harmonized European procedure to demonstrate conformity and to support acceptance testing alongside EN 4057-100.

Benefits include:

• A standardized method to assess and compare burning characteristics.
• Clear apparatus and calibration steps to improve repeatability between laboratories.
• Actionable observations (afterflame time, falling particles) to inform part acceptance or design changes.

Related Standards

• EN 4057-100 - Aerospace series - Cable ties for harnesses - Test methods - Part 100: General (normative reference).
• Other regional or industry flammability test methods may be referenced for broader electrical system fire-safety evaluation; use EN 4057-302:2006 specifically for cable tie harness components.

For implementation, follow the document's apparatus calibration and observation guidance precisely and record results together with the general test conditions defined in EN 4057-100. This ensures consistent, defensible flammability data for aerospace cable ties and harness assemblies.