Externally Provided Products and Services Procedure
| Procedure number | 06 |
| ISO/IEC 17025 reference | Clause 6.6 |
| Revision | 00 |
| Effective date | [Enter date] |
| Approved by | [Quality Manager / Laboratory Director] |
1. Purpose
To ensure that externally provided products and services that affect laboratory activities are evaluated, selected, monitored, and controlled so that they do not compromise the validity of results.
2. Scope
This procedure applies to all externally provided products and services that directly or indirectly affect the quality of laboratory results, including:
- Reference standards and certified reference materials (CRMs) — Multi-element ICP standards, cathode and anode material CRMs, matrix-matched reference samples
- Reagents and chemicals — High-purity acids (HNO₃, HCl, HF) for sample digestion, HPLC-grade solvents, Karl Fischer reagents
- Calibration services — External calibration of instruments and reference equipment (balances, thermometers, volumetric glassware)
- Subcontracted testing — Analyses that the laboratory cannot perform in-house (e.g., particle morphology by SEM, trace impurity screening by ICP-MS)
- Equipment maintenance and repair services — Manufacturer or third-party service for ICP-OES, HPLC, BET, XRD, and supporting equipment
- Gas supplies — Argon for ICP-OES plasma, nitrogen and helium for BET analysis
- Proficiency testing providers — External PT scheme organizers for interlaboratory comparisons
- Software and data services — LIMS providers, instrument software updates, cloud data storage
This procedure does not cover general office supplies or services that have no bearing on measurement quality.
3. References
- ISO/IEC 17025:2017, Clause 6.6 — Externally provided products and services
- ISO/IEC 17025:2017, Clause 7.1.1 — Review of requests, tenders and contracts
- ISO/IEC 17025:2017, Clause 7.8 — Reporting of results
- ISO 17034 — General requirements for the competence of reference material producers
- ISO/IEC 17043 — Conformity assessment — General requirements for proficiency testing
- ISO Guide 33 — Reference materials — Good practice in using reference materials
- Procedure 00 — Document and Record Control
- Procedure 05 — Addressing Risks and Opportunities
- Procedure 08 — Equipment Maintenance, Calibration and Verification
4. Definitions
| Term | Definition |
|---|---|
| Externally provided product | Any physical item obtained from an external source that affects laboratory activities — reference materials, reagents, consumables, equipment, gases. |
| Externally provided service | Any service obtained from an external source that affects laboratory activities — calibration, subcontracted testing, equipment maintenance, proficiency testing. |
| Supplier | Any organization or individual that provides products or services to the laboratory. Includes manufacturers, distributors, service providers, and subcontractors. |
| Approved supplier | A supplier that has been evaluated and determined to meet the laboratory's requirements. Only approved suppliers may be used for critical products and services. |
| Critical product or service | A product or service whose quality directly affects the validity of test or calibration results. Examples: CRMs, calibration services, subcontracted analyses. |
| Certified reference material (CRM) | A reference material accompanied by a certificate providing one or more certified property values with associated uncertainties and traceability statements. |
| Subcontracting | Engaging another laboratory to perform part or all of a test or calibration on behalf of this laboratory. |
| Certificate of analysis (CoA) | Documentation from a supplier certifying the properties, purity, or characteristics of a delivered product, including measurement traceability information. |
5. Responsibilities
| Role | Responsibility |
|---|---|
| Laboratory Director | Approve subcontracting arrangements. Ensure adequate budget for quality-critical supplies. |
| Quality Manager | Maintain the Approved Supplier List (06-App-02). Coordinate supplier evaluations and reviews. Ensure supplier records are current and complete. |
| Technical Manager | Define technical requirements for critical products and services. Evaluate technical performance of suppliers. Approve incoming critical materials. |
| Analysts | Verify incoming products against specifications. Report any quality concerns or nonconformities to the Technical Manager. |
| Purchasing personnel | Place orders only with approved suppliers for critical items. Retain purchase records. |
6. Procedure — Defining Requirements
6.1 Identifying critical products and services
The Technical Manager, in consultation with the Quality Manager, maintains a classification of externally provided products and services into two categories:
Critical — Products or services whose quality directly affects the validity of results. These require formal supplier evaluation and approval before use. Examples:
- Certified reference materials and calibration standards
- High-purity reagents used in sample preparation (e.g., trace-metal grade HNO₃ for ICP-OES digestion)
- Calibration services for measurement equipment
- Subcontracted testing or calibration
- Proficiency testing schemes
- Gases used as instrument operating media (e.g., argon plasma gas)
Non-critical — Products or services that support laboratory operations but do not directly affect result validity. These are managed through normal purchasing controls. Examples:
- General laboratory consumables (pipette tips, sample containers, filters)
- Office and IT supplies
- Facility maintenance services (cleaning, HVAC servicing)
The classification is reviewed annually or when new products, services, or methods are introduced.
6.2 Specifying requirements
For each critical product or service, the Technical Manager documents the requirements that the supplier must meet. These typically include:
For reference materials and reagents:
- Required purity grade or certified values with uncertainties
- Traceability to SI units or recognized references
- Shelf life and storage conditions
- Certificate of analysis (CoA) with each delivery
- Compliance with ISO 17034 (for CRM producers)
For calibration services:
- Accreditation to ISO/IEC 17025 for the relevant calibration scope
- Traceability to national or international measurement standards
- Calibration certificates with measurement uncertainty statements
- Turnaround time requirements
For subcontracted testing:
- Accreditation to ISO/IEC 17025 for the relevant test scope
- Agreed methods, reporting format, and turnaround time
- Confidentiality and data protection requirements
- How results will be reported (directly to customer or back to this laboratory)
For proficiency testing:
- Provider accredited to ISO/IEC 17043
- Scheme relevant to the laboratory's scope of testing
- Frequency aligned with accreditation body requirements
7. Procedure — Supplier Evaluation and Approval
7.1 Initial evaluation
Before a supplier is used for the first time for a critical product or service, the Quality Manager (with input from the Technical Manager) conducts an evaluation. The evaluation considers:
- Accreditation or certification status — Is the supplier accredited to a relevant standard (ISO/IEC 17025, ISO 17034, ISO/IEC 17043)? Accreditation provides a presumption of competence for the accredited scope.
- Track record and reputation — Published references, peer laboratory experience, industry standing.
- Technical capability — Can the supplier meet the laboratory's documented requirements? Review of certificates, CoAs, or sample reports.
- Quality system — Does the supplier operate under a quality management system? (For non-accredited suppliers.)
- Delivery and logistics — Reliability of supply, lead times, packaging, transport conditions (cold chain if required).
- Commercial terms — Pricing, payment terms, minimum order quantities. (Commercial factors alone do not override technical suitability.)
The evaluation is documented in Appendix 06-App-01 — Supplier Evaluation and Approval Record.
7.2 Approval decision
Based on the evaluation, the supplier is assigned one of three statuses:
| Status | Meaning |
|---|---|
| Approved | The supplier meets all requirements and may be used for the evaluated scope of products or services. |
| Conditionally approved | The supplier meets most requirements but has minor gaps. May be used subject to additional verification (e.g., incoming inspection of every delivery). Conditions and expiry are documented. |
| Not approved | The supplier does not meet requirements. Products or services from this supplier must not be used. |
The Quality Manager records the decision and adds approved suppliers to the Approved Supplier List (Appendix 06-App-02).
7.3 Accredited suppliers
When a supplier holds current accreditation to a relevant ISO standard (e.g., ISO/IEC 17025 for calibration, ISO 17034 for reference material production), and the products or services fall within the supplier's accredited scope, the accreditation itself constitutes sufficient evidence of technical competence. In this case:
- The evaluation focuses on verifying that the specific product or service is within the accredited scope
- The laboratory records the accreditation body, certificate number, and scope
- No additional technical audit is required
The laboratory must verify that accreditation remains current. This is checked at each re-evaluation (section 8.2).
7.4 Subcontractors
When the laboratory subcontracts testing or calibration:
- The subcontractor must be accredited to ISO/IEC 17025 for the relevant scope, unless the customer accepts an alternative arrangement.
- The customer must be informed of the subcontracting arrangement and, where required, give written approval before work begins.
- The laboratory retains responsibility for the subcontractor's work and includes subcontracted results in its own reports, clearly identified as subcontracted.
- A formal agreement or contract defines responsibilities, methods, reporting, confidentiality, and dispute resolution.
8. Procedure — Monitoring and Re-evaluation
8.1 Incoming verification
When critical products are received, the analyst or Technical Manager performs incoming verification appropriate to the product type:
Reference materials and CRMs:
- Verify the CoA is present, current, and includes certified values with uncertainties and traceability statements
- Check that the material is within its validity period
- Verify packaging integrity and storage conditions during transport
- For new lots: compare an initial measurement against the certified value using an existing verified standard
Reagents and chemicals:
- Verify the CoA or specification sheet matches the order
- Check purity grade, lot number, expiry date
- Inspect packaging for damage, leaks, or contamination
- For critical reagents (e.g., trace-metal grade acids): run a blank to verify purity before use
Calibration certificates:
- Verify the certificate includes measurement uncertainty, traceability statement, and identification of the calibrated item
- Confirm the calibration was performed by an accredited laboratory (where required)
- Check that results are within the laboratory's acceptance criteria
Gas supplies:
- Verify purity grade matches specification
- Check cylinder condition and labeling
- For critical gases (e.g., argon for ICP-OES): monitor instrument performance after cylinder change
Any nonconformity is handled according to Procedure 14 — Complaints, Nonconformity and Corrective Action.
8.2 Periodic re-evaluation
Approved suppliers are re-evaluated at defined intervals to confirm continued suitability:
| Supplier type | Re-evaluation interval |
|---|---|
| CRM and reference standard suppliers | Every 2 years, or when a quality issue arises |
| Calibration service providers | Every 2 years, or after each calibration event (review of certificate) |
| Subcontracted laboratories | Annually, or after each subcontracted job |
| Reagent and chemical suppliers | Every 2 years, or when a quality issue arises |
| PT providers | Every 2 years |
| Equipment service providers | Every 2 years, or after each service visit (review of service report) |
Re-evaluation considers:
- Delivery performance (on time, correct quantities, proper packaging)
- Product quality (any nonconformities, deviations from specifications)
- Certificate and documentation quality
- Maintenance of accreditation or certification (verified against accreditation body registers)
- Resolution of any past issues or complaints
The re-evaluation is documented in a new Appendix 06-App-01 record. The Approved Supplier List is updated accordingly.
8.3 Supplier nonconformity
When a supplier delivers a product or service that does not meet requirements:
- The product or service is quarantined or flagged and not used until the issue is resolved.
- The Technical Manager assesses the impact on any results already reported using the affected product or service.
- The supplier is notified and required to respond with a corrective action.
- The incident is recorded on the supplier's evaluation record and considered in the next re-evaluation.
- Repeated or critical nonconformities may result in conditional approval, suspension, or removal from the Approved Supplier List.
9. Procedure — Records
The Quality Manager maintains the following records:
| Record | Retention | Location |
|---|---|---|
| Supplier evaluation and approval records (06-App-01) | Duration of supplier relationship + 5 years | [Specify] |
| Approved Supplier List (06-App-02) | Current version + all previous versions | [Specify] |
| Certificates of analysis for reference materials | Validity period of material + 5 years | [Specify] |
| Calibration certificates (received) | Calibration interval + 5 years | [Specify] |
| Subcontracting agreements | Duration of agreement + 5 years | [Specify] |
| Purchase orders for critical supplies | 5 years | [Specify] |
| Incoming verification records | 5 years | [Specify] |
Records are managed according to Procedure 00 — Document and Record Control.
10. Related documents
| Document | Reference |
|---|---|
| Appendix 1 — Supplier Evaluation and Approval Record | 06-App-01 |
| Appendix 2 — List of Approved Suppliers | 06-App-02 |
| Procedure 00 — Document and Record Control | Procedure 00 |
| Procedure 05 — Addressing Risks and Opportunities | Procedure 05 |
| Procedure 08 — Equipment Maintenance, Calibration and Verification | Procedure 08 |
| Procedure 14 — Complaints, Nonconformity and Corrective Action | Procedure 14 |
11. Revision history
| Revision | Date | Description | Approved by |
|---|---|---|---|
| 00 | [Date] | Initial issue | [Name] |
Why this section exists
Section 06 addresses a dependency that laboratories often underestimate: the quality of results is bounded by the quality of what enters the laboratory from outside.
A laboratory can have flawless analysts, perfectly maintained instruments, and rigorously validated methods — and still produce wrong results if the calibration standard it purchased has a certified value that is incorrect, or if the acid used for digestion contains trace-level contamination at the concentrations being measured.
The accreditation shortcut and its limits
ISO/IEC 17025 provides a useful simplification: if a supplier is accredited for the relevant scope, that accreditation constitutes presumptive evidence of competence. For CRM producers accredited to ISO 17034, for calibration laboratories accredited to ISO/IEC 17025, the laboratory does not need to conduct its own technical audit.
But this shortcut has limits that are frequently overlooked. Accreditation covers a defined scope — and the product or service the laboratory is purchasing must actually fall within that scope. A CRM producer accredited for water matrix reference materials is not necessarily competent to produce cathode material CRMs. A calibration laboratory accredited for mass calibration is not necessarily accredited for temperature calibration. The laboratory must verify scope, not just the existence of accreditation.
The other limit is temporal. Accreditation can be suspended, reduced, or withdrawn. A supplier that was accredited when initially approved may not be accredited today. Checking current accreditation status — not just the certificate on file — is part of every re-evaluation.
Certificates of analysis are evidence, not decoration
A CoA that accompanies a reference material is not a receipt. It is a metrological document that links the laboratory's measurements to the international measurement system. The certified values, their uncertainties, the traceability chain, and the validity period are all load-bearing.
When a CoA arrives with a delivery, someone in the laboratory must actually read it. Verify that the certified values cover the elements or properties the laboratory needs. Verify that the uncertainties are small enough for the laboratory's required measurement capability. Verify that the traceability chain terminates at recognized national or international standards. Verify that the material has not expired.
This sounds obvious, but auditors routinely find laboratories using CRMs with expired certificates, or CRMs whose certified values do not cover the measurand of interest, or CRMs with no traceability statement at all. Section 06 exists in part to prevent exactly this.
Lot changes are invisible method changes
When a reagent supplier changes a lot number, the laboratory receives what appears to be the same product. Same catalog number, same label, same grade designation. But the new lot is a different batch — manufactured at a different time, possibly from different raw materials, with different trace impurity levels.
For most routine reagents this makes no practical difference. But for trace analysis — which is exactly what ICP-OES work on battery materials involves — a lot change in the digestion acid can shift the blank signal enough to affect results near the reporting limit. A lot change in an HPLC mobile phase solvent can shift retention times.
The incoming verification step in this procedure exists precisely for these transitions. When a new lot of a critical reagent arrives, the laboratory runs a blank or a control before committing samples. This is not excessive caution — it is a basic control against an invisible variable.
The subcontracting trap
Subcontracting carries a specific risk that is easy to miss: the laboratory remains responsible for results it did not produce. When a battery materials laboratory subcontracts SEM imaging of particle morphology, the report that goes to the customer includes those results under the laboratory's name. If the subcontractor's measurements are wrong, it is the laboratory — not the subcontractor — that faces the consequences.
This is why clause 6.6 requires that subcontractors be accredited for the relevant scope, that the customer is informed, and that a formal agreement defines responsibilities. The agreement is not a commercial formality. It is the document that clarifies who is responsible for what when something goes wrong.