How should family strategy differ for mirrors, glazing, tyres, lamps and wheels?

General principles

• Start with the intended certification scope, not a desired reduction in sample count.
• Identify the type/family definition in each applicable QCVN or UN Regulation.
• Map characteristics → test → failure mode.
• Select a representative or worst-case sample for each test where technically justified.
• Check whether the remaining variants are covered by the evidence and type definition.

By product group

Mirrors/CMS: consider type, geometry, mounting or field of view and test-relevant characteristics under QCVN 28/33 and R46 where applicable.

Glazing: consider glazing category, construction, thickness/dimensions and type-defining characteristics under QCVN 32/R43.

Tyres: consider size, category, load/speed, construction and intended use, and the requirements of QCVN 34/36 and R30/R54/R75 where applicable.

Lamps: consider function, category, light source, optical characteristics and scope under QCVN 125/R149 or the referenced UN Regulation.

Wheels: consider dimensions, material, geometry, application and type/family under QCVN 78/113/R124 where applicable.

These factors provide a guidance framework; the specific definitions and test clauses must be read before finalizing the family.

Basis

LEGAL REQUIREMENT: Type, family and sample requirements must follow the applicable QCVN and UN Regulation. A family must not be created solely from a commercial model grouping.

Expert analysis

EXPERT INTERPRETATION: Family strategy is a coverage-optimization exercise within regulatory constraints, not simply an exercise in reducing sample count.

EXPERIENCE-BASED INSIGHT: LotusTSE does not use one universal worst case. Representative samples are selected from characteristics that influence each test and the intended certification scope. A family subject to multiple tests may require multiple representative samples.

Risks

Grouping a family too broadly; selecting the largest or heaviest sample by intuition; overlooking optical, material or construction differences; directly reusing a UNECE family for QCVN without mapping; changing a variant after testing.

Approach

1. Variant master list.

2. Regulatory type/family rules.

3. Characteristic-to-test matrix.

4. Representative-sample rationale.

5. Coverage matrix and residual gaps.

6. Expert or laboratory confirmation where needed.

LotusTSE support

Family strategy; sample selection; test plan; evidence-reuse analysis; certification-scope planning.

Knowledge Graph

QCVN: 28, 32, 33, 34, 36, 78, 113 and 125.

UNECE: R30, R43, R46, R54, R75, R124 and R149.

Related: Representative Samples; Dossier Errors; Test Report vs Certificate.

NEEDS VERIFICATION

The family definition, test grouping and final sample selection must be verified against the applicable QCVN and UN Regulation clauses and the laboratory’s capabilities and test plan for each project.