Glass Fragmentation Test — UNECE R43 / ECE R43

What Is Fragmentation?

The fragmentation test evaluates the number and size of fragments produced when toughened safety glass breaks. Correctly tempered glass breaks into small, blunt granules rather than long sharp shards; the test verifies this behaviour.

Purpose of Fragmentation

The purpose is to verify that the glass exhibits a fragment pattern that limits the risk of injury if it breaks, and to produce evidence for vehicle-glass type approval.

Which Products Is Fragmentation Applied To?

Toughened side and rear vehicle glass
Panoramic glass roofs
Bus and commercial-vehicle glass
Toughened glass partitions

In Which Sectors Is Fragmentation Used?

AutomotiveConstructionGlass

Standards Related to Fragmentation

UNECE R43safety glasses test
ECE R43 Annex 5
ANSI Z26.1
ISO 3537

Fragmentation Conditions

Breaking point: Broken with a pointed tool at the points specified by the standard
Counting area: Fragments within a square area of the size defined in the standard are counted
Conditioning: The test is performed under standard temperature conditions

Equipment for Fragmentation

Breaking tool (punch)
Counting templates
Illuminated counting table or photography rig
Measuring ruler and calipers
Conditioning chamber

Sample Requirements for Fragmentation

Complete glass specimens representing series production
The number of specimens prescribed by the standard
Glass thickness, coating and tempering information must be stated
The test is destructive; each specimen is single-use

Duration of Fragmentation

The test is short per specimen; together with counting and assessment, the result is obtained within a few days.

Fragmentation Procedure

1The specimen description, thickness and dimensions are recorded.
2The specimen is conditioned and placed in the test rig.
3It is broken at the point specified by the standard.
4After breaking, the glass is left undisturbed for the specified duration.
5Fragments in the defined area are counted using the counting template.
6The longest fragment is measured.
7Results are compared with the standard's requirements.

Fragmentation Acceptance Criteria

Under UNECE R43, acceptance is that the number of fragments in the defined counting area falls between the lower and upper limits stated in the standard, and that the longest fragment does not exceed the permitted length. Exact values are taken from the standard's relevant annex.

Evaluation of Results

A low fragment count indicates insufficient tempering, while an excessively high count indicates excessive stress. Long, sharp fragments are a direct cause of non-conformity.

Fragmentation Report

Applied standard and annex
Sample description, thickness and dimensions
Breaking point and conditions
Counting area and fragment counts
Longest-fragment measurement
Photographs

Accreditation

EUROLAB holds internationally recognised accreditation obtained from accreditation bodies party to the IAF and ILAC multilateral recognition arrangements, under ISO/IEC 17025 for laboratory testing, ISO/IEC 17020 for inspection and surveillance, and ISO/IEC 17021-1 and ISO/IEC 17065 for system and product certification. This chain ensures the reports and certificates issued are accepted worldwide.

Whether this test can be offered within accredited scope depends on your product and the standard applied; since accreditation is method-based, the scope is confirmed in writing at the quotation stage.

Scope and authorisations

Related Regulations

UNECE R43
Vehicle type-approval legislation

Otomotiv Testleri — What Does This Testing Field Cover?

The section below describes the field that the Fragmentation test belongs to; the conditions and acceptance criteria of this particular test are given in the sections above. The scope specific to your product is confirmed in writing at the quotation stage.

Automotive testing shows that a component keeps working under conditions representing the loads it will meet over the life of the vehicle. A vehicle is not a single product but an ENVIRONMENT: vibration, temperature cycling, salt water, stone impact, electrical transients and electromagnetic noise are all present at the same time and for years.

What distinguishes this family is that VEHICLE MANUFACTURER SPECIFICATIONS sit on top of the standards. ISO and SAE publications establish the common ground; but Volkswagen, BMW, Ford, Stellantis, Toyota and Renault define different severity levels, additional tests and different acceptance criteria in their own specifications. For a component, the phrase "complies with automotive standards" is not sufficient on its own; which manufacturer's specification, and which revision of it, must be answered.

The family carries three separate processes together and they are often confused. Homologation covers the type approvals a vehicle needs to enter traffic and runs under state authority. Supplier approval means passing the vehicle manufacturer's own quality and testing requirements and is a commercial relationship. The third is design verification: the engineering team demonstrating that its own design meets its targets.

At component level the test plan is built around the LOCATION OF USE. A module in the engine bay and a module in the boot do not go through the same temperature and vibration profile; a component inside a door and one in the roof console do not see the same water and dust exposure. The ISO 16750 series is the common framework for this location-based approach.

The shift to electric vehicles has reshaped the field. High-voltage safety, insulation coordination, battery safety, charging interface conformity and the electromagnetic behaviour of high-voltage components have been added to the classical automotive test set. In a quiet vehicle, acoustic and vibration expectations have changed too; sounds once masked by the combustion engine are now audible.

The quality system side cannot be separated from testing in this field. A manufacturer under IATF 16949 presents test results in the PPAP file; measurement system analysis, process capability study and the control plan stand around the test report. A single good result is not enough — the process must be shown to be able to repeat it.

Method groups in this field

Environmental and climatic
Temperature cycling, thermal shock, damp heat, salt spray, dust and water ingress (IP), solar radiation. Severity levels vary with the mounting location.
Mechanical
Sine and random vibration, shock, mechanical loads, fastener torque and durability cycles.
Electrical
Supply voltage variations, transients (ISO 7637), reverse polarity, overvoltage, short circuit and sleep current measurements.
EMC
Component emissions (CISPR 25), radiated and conducted immunity (ISO 11452 series), electrostatic discharge (ISO 10605).
Materials and emissions
Odour, fogging and VOC emissions from interior materials; flammability; UV ageing; coating durability and stone impact.
Functional safety and cyber security
Functional safety evidence under ISO 26262 and cyber security engineering under ISO/SAE 21434; these are tied to regulation through UNECE R155 and R156.

Commonly confused in this field

An automotive report without a specification reference is not accepted in the supply chain; which OEM specification and revision was applied must be stated.
Type approval and supplier approval are different processes. A component with E-Mark approval is not thereby considered to have passed the OEM's own acceptance tests.
A result obtained on a prototype does not carry over to series production; PPAP is done with series production parts.
On the EMC side, measuring emissions alone is incomplete; immunity is a separate body of work and is more critical in a vehicle.
On electric vehicle components, high-voltage safety is a distinct competence; classical 12 V test infrastructure is not sufficient.

Which decisions these results support

Supplier component approval and the PPAP file
UNECE type approval and E-Mark marking
Design verification and durability evidence
Root cause analysis of field complaints and warranty returns
Assessing the impact of a design or supplier change

Related Tests

Frequently Asked Questions About Fragmentation

Is the fragmentation test also performed on laminated glass?

Laminated glass is subject to different tests. In laminated glass, the interlayer holds the fragments together; evaluation is therefore performed on penetration resistance, head impact and interlayer adhesion rather than fragment counting.