Product and process audits are essential quality assurance tools used across manufacturing industries, especially in automotive OEMs and Tier 1 suppliers. These audits verify whether processes follow the defined standards and whether the final product meets customer requirements. In the automotive sector governed by IATF 16949, both process audits and product audits play a critical role in maintaining consistency, reducing defects, and improving customer satisfaction.
This article explains the meaning of product and process audits, their differences, checklists, automotive examples, IATF requirements, and a step-by-step guide for conducting audits. It incorporates high-search-volume queries such as automotive process audits, IATF manufacturing process audit checklist, product audit vs process audit, and manufacturing process audit.
- What is a Process Audit?
- What is a Product Audit?
- Product Audit vs Process Audit – Key Differences
- Automotive Process Audits – Explanation with Examples
- IATF 16949 Requirements for Process Audits
- Manufacturing Process Audit Checklist (IATF-Based)
- Product Audit Checklist
- How to Conduct a Process Audit – Step-by-Step Guide
- Common Non-Conformities found in Process Audits
- Frequently Asked Questions (FAQ)
- What is the difference between a process audit and a product audit?
- What is included in a process audit checklist?
- How do you conduct a process audit in the automotive industry?
- What is a manufacturing process audit?
- What is a product audit checklist?
- What are the IATF 16949 requirements for process audits?
- How often should process audits be done?
- What is a layered process audit (LPA)?
- Process Audit checklist:
- Conclusion
What is a Process Audit?
A process audit is a systematic evaluation of a manufacturing or service process to verify whether it follows the defined procedures, control plans, work instructions, PFMEA controls, and customer-specific requirements. It focuses on process effectiveness, capability, stability, operator competencies, and compliance with IATF 16949 requirements.
Process audits answer questions such as:
- Is the process running as per the defined method?
- Are process parameters within standard control limits?
- Are operators following correct work instructions?
- Are all Poka-Yoke, gauges, and machines functioning properly?
Process audits focus on how the product is made, not on the product itself.
What is a Product Audit?
A product audit evaluates the final output or finished product to ensure that it meets specifications, drawings, dimensional requirements, visual standards, functional parameters, and customer expectations.
Product audits answer:
- Does the product meet the design and drawing requirements?
- Is the product visually acceptable?
- Do functional features work correctly?
- Is the packaging, labelling, and marking correct?
Product audits focus on what is produced.
Product Audit vs Process Audit – Key Differences
Customers often search for “process audit vs product audit,” so a clear comparison table helps SEO and user understanding.
| Factor | Process Audit | Product Audit |
|---|---|---|
| Focus | Manufacturing process steps | Final product output |
| Purpose | Verify process compliance, stability & controls | Verify final product conformity |
| Frequency | Daily/weekly/monthly, depending on need | Monthly/quarterly, depending on customer requirements |
| Auditor | Internal auditor, process engineer, LPA auditor | Quality engineer or trained auditor |
| Documents Referenced | Control Plan, PFMEA, Work Instructions, SOP, Process Flow | Drawing, Specification, Customer standards, Appearance master |
| Output | Process improvements, corrective actions | Conformity verification & defect detection |
| Industry Use | Automotive, aerospace, electronics and machining | Automotive, consumer goods, safety-critical components |
Both audits complement each other and strengthen the overall quality system.
Automotive Process Audits – Explanation with Examples
Automotive industries (MSIL, Tata, Mahindra, Hyundai, Honda, Toyota, etc.) rely heavily on process audits to ensure the robustness of manufacturing processes. These audits help detect non-conformities early, strengthen process controls, and reduce customer complaints.
Common Automotive Examples:
- Press Shop: Checking die setup, lubrication, feed rate, part orientation, dimensional control, and burr control.
- Welding Line: Verifying welding parameters, fixtures, electrode dressing, and cycle time monitoring.
- Machining Line: Checking tool life monitoring, gauge usage, SPM settings, coolant flow, Cp/Cpk levels.
- Assembly Line: Torque setting verification, Poka-Yoke function checks, and correct part assembly sequence.
Automotive process audits strongly link with Layered Process Audits (LPA), which require supervisors, engineers and managers to audit daily/weekly using structured checklists.
IATF 16949 Requirements for Process Audits
IATF 16949 mandates organisations to perform process audits to ensure:
- Compliance with Control Plan
- Linkage to PFMEA controls
- Verification of special characteristics
- Operator training competence
- Process capability (Cp/Cpk) monitoring
- Gauge calibration
- Reaction plan and non-conformity control
- Implementation of Poka-Yoke and error-proofing systems
- Supplier process audits (Tier-1 and Tier-2)
These audits ensure consistent, defect-free production and customer satisfaction.
Manufacturing Process Audit Checklist (IATF-Based)
1. Input Material Control
- Correct material grade
- Material test certificates
- FIFO compliance
2. Process Controls
- Parameter verification
- Monitoring of special characteristics
- Proper machine setup and alignment
3. Operator Competence
- Operator training records
- Skill matrix compliance
- SOP & Work Instruction understanding
4. Equipment Condition
- Preventive maintenance records
- Tooling condition
- Poka-Yoke functionality
5. Gauges & Measurement
- Gauge calibration status
- Proper gauge usage
- MSA (Measurement System Analysis) inputs
6. Documentation Check
- Control plan availability
- PFMEA linkages
- Work instructions visibility
7. Reaction Plan
- Handling of non-conforming parts
- Escalation process
- Containment actions
8. Safety & Environment
- PPE usage
- Machine guarding
- Safety compliance
This checklist improves audit consistency.
Process Audit Check Sheet Download PDF
Product Audit Checklist
Product audit checklist includes:
1. Dimensional Check
- Critical dimensions
- Gauge verification
- Go/No-Go checks
2. Visual Inspection
- Scratches, burrs, dents, etc
- Colour/finish
- Overall appearance
3. Functional Testing
- Electrical/torque/pressure tests
- Assembly fitment
- Performance checks
4. Packaging Check
- Correct packaging
- Labelling, barcodes
- Customer-specific requirements
5. Documentation
- Drawing verification
- Customer standards
- Inspection report
Product audits ensure conformity as per the Control Plan requirements.
How to Conduct a Process Audit – Step-by-Step Guide
Follow these steps to perform a professional process audit:
1. Define the Scope
Identify the process, machine, cell, or area to audit.
2. Prepare the Process Audit Checklist
Use IATF-based requirements for consistency.
3. Visit the Shopfloor
Observe real practice vs documented standards.
4. Interview Operators
Verify their understanding of work instructions, safety, and checkpoints.
5. Verify Process Documents
Check the control plan, PFMEA, SOP, and process flow diagram.
6. Check Machines, Tools, Gauges
Verify capability, calibration and maintenance status.
7. Identify Gaps and Record Evidence
Take photographs (if allowed), note non-conformities, deviations, and risks.
8. Generate Audit Report
Include observations, NCs, risks, and improvement actions.
9. Close Corrective Actions (8D)
Use 8D / CAPA methodology for closure.
For corrective actions, refer to our 8D Problem Solving Guide.
Common Non-Conformities found in Process Audits
- Missing control plans/operation standard, or a wrong revision
- Operators not following SOP
- Improper gauge usage
- Machine parameters outside limits
- Missing reaction plans
- Incorrect torque values
- Bypassed Poka-Yoke
- Poor housekeeping (5S violations)
These issues significantly affect process capability and product quality.
Frequently Asked Questions (FAQ)
What is the difference between a process audit and a product audit?
A process audit checks process methods, and a product audit checks the final product. Both support quality assurance.
What is included in a process audit checklist?
Operator competency, process parameters, control plan adherence, gauge usage, machine condition, Poka-Yoke, and reaction plan.
How do you conduct a process audit in the automotive industry?
Follow the IATF control plan, PFMEA linkages, special characteristics, operator checks, and LPA-based verification.
What is a manufacturing process audit?
An audit that checks process effectiveness, capability, compliance with SOP, PFMEA, and customer requirements.
What is a product audit checklist?
Dimensional, visual, functional, packaging, and documentation checks.
What are the IATF 16949 requirements for process audits?
Control plan implementation, monitoring of special characteristics, PFMEA linkage, training, error-proofing, calibration, and reaction plans.
How often should process audits be done?
Monthly / Quarterly, depending on risk, customer requirements, and part criticality.
What is a layered process audit (LPA)?
A daily/weekly audit is performed by supervisors, engineers, and managers to verify process compliance.
Process Audit checklist:
- Are previous audit observations closed? : Verify that the previous audit NCs are closed or not.
- Is the operator working as per the operation standard/WI? : Check the working of operators as written in WI / OPS. Check that they are doing all activities like cleaning, part inspection by gauge, comparing with the limit sample etc.
- Verify the Process Flow Chart / Process Sequence of the running component. : Check that all process sequences are OK as per PFD.
- Check the availability of Process Control Standards (Operation Standards/WIs) on the machine.: Operation Standard and WI should be displayed on the machine in front of operators.
- Verify the process parameters as per the Control Plan / Operation Standard on the machine. : All product and process parameters should be OK as per the control plan. Verify with the Control Plan that all parameters should be within specification.
- Check the records as mentioned in Control Plan / Operation Standard: There should be a record of setup approval and in-process inspection as per the defined frequency by a competent inspector.
- Verify that all the measuring instruments/ Gauges are calibrated & check the validity / Expiry date. All instruments in use should be calibrated. Verify with calibration sticker, calibration plan and calibration certificates.
- Verify that the daily machine check sheet is properly filled. Check that the daily machine check sheet is filled correctly. Also, verify the actual condition of machines as per checkpoints.
- Check for the Legibility/Visibility of all the displayed documents. Documents on the machine should be readable and visible, like font size, paper size etc.
- Check for the availability of Master samples / Limit Samples / FOP samples etc. Check the condition and due date of the limited samples. Also in the First part approval sample date and the inspector’s signature.
- Verify proper disposition of Non-conforming products.: Check the rework record and rejection record for non-conforming parts. Also in the Red bins should not be filled with non-conforming parts.
- Check the competency of the Operator / Inspector. Verify the skill level of operators and inspectors as per the Skill matrix.
- Verify the Countermeasures of problems (Internal & External): Check for previous one-year countermeasures for internal and customer complaints in that part.
- Check & verify the Machine / Tool / Jig / Fixture conditions (Maintenance of Production Equipment / Machine/ Tool). Check records of preventive maintenance as per plan.
- Verify the effective implementation/functioning of the Poka-Yoke Mechanism. Check the poka yoke record and the actual work on the machines.
- Check for identification & traceability. All the parts must be properly identified & traceable. There should be an identification tag on all parts with a batch number or lot number for traceability.
- Verification of Change Management. Inspection records must be maintained for unplanned/abnormal changes (Setup, Retroactive & Containment). Verify the change record with the tracking sheet and 4M change setup approval record.
- Verify the implementation of Safety measures on the shop floor. PPEs (Helmet, Goggles, Gloves, Apron, Nose masks, Shoes, Ear Plugs etc.) must be effectively used on the shop floor as per the PPE’s matrix area-wise.
- Check the availability of Red/Yellow/Ok Bins on the shop floor. There should not be any shortage of bins and trolleys in the shop floor. No material should be lying on the floor. Also, no overflow in bins and trolleys.
- Verify Lux level at production & final inspection area. Verify the lux level with the Lux meter and the Lux level should be as per the standard. Generally lux level should be min 750 in the final inspection area and 300 in the production area.
- Verify FIFO in each area. FIFO should be implemented in each RM, WIP and FG area. There should be a FIFO board in each area for FIFO implementation.
- Verify the process with PFMEA during process audit and check all points are covered in PFMEA. There should be a linkage between the PFMEA and the Control Plan.
- Verify housekeeping in each area. Housekeeping should be maintained. There should be 5S audit plan and a 5S audit check sheet.
- Verify Packaging & Labelling as per packing standards. Packaging & Labelling should be done as per packing standards. Packing Standard should be displayed in the final packing area.
Download the Process Audit Check Sheet (Excel)
Conclusion
Product and process audits strengthen the foundation of a Quality Management System, particularly in the automotive and engineering industries. They ensure processes are stable, capable, and compliant with IATF 16949 requirements. By using structured checklists, understanding the differences between product and process audits, and performing regular shopfloor assessments, organisations can prevent defects, reduce rejections, and improve customer satisfaction.
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