Quality management tools: A thinking toolbox from chaos to order
The core of quality management is to use structured tools to break down vague problems, integrate scattered information, and make implicit risks explicit. The following ten types of quality tools cover the entire scenarios from task implementation to problem - solving, and from production monitoring to system construction. In essence, they are a set of thinking methods that "provide a framework for actions and a basis for decisions".
I. 5W3H: Transform "vague tasks" into "implementable actions" with 8 questions
5W3H is the most basic task decomposition framework. It covers all dimensions of "what to do, why to do it, and how to do it" through eight questions, helping you transform "roughly going to do something" into "clear action steps":
Why (Why): Anchor the purpose of the task – avoid doing things just for the sake of doing them. For example, Why do we need to optimize this production line? The answer might be to reduce the defect rate by 10% rather than it's a requirement from the leadership.
What (What to do): Define the boundaries of the task - clearly state the goals to be achieved and the things not to do. For example, optimize the production line means adjust the sequence of processes rather than update all equipment.
Where (Where): Match the "scene" of the task - select the optimal execution location. For example, it is more efficient to conduct "part inspection" at the end of the production line than in the warehouse.
When (): Plan the "rhythm" of tasks - set the time nodes for start, end, and inspection. For example, "Start this Wednesday, finish next Friday, and check the progress every Friday afternoon."
Who (Who will do it): The responsibility of a closed-loop task— clearly define the executor and the person in charge. For example, Zhang San is responsible for adjusting the process, and Li Si is responsible for acceptance, to avoid the situation where everyone is responsible = no one is actually responsible.
How (How to do it): Design the "path" of the task - replace experience with more efficient methods. For example, "using automated equipment to replace manual sorting" can improve efficiency more effectively than "hiring more workers".
How much (Cost and Effect): Weigh the input - output of the task — quantify the cost (e.g., invest 50,000 yuan) and the effect (e.g., reduce the defective rate from 15% to 5%), and avoid overspending for optimization.
How feel (Result prediction): Evaluate the "impact" of the task - think in advance "What consequences will there be after doing it?" For example, "Will adjusting the process lead to a temporary decline in production?"
The essence of 5W3H is to transform "implicit needs" into "explicit action lists" with eight questions. It is suitable for all tasks that need to be implemented, ranging from "organizing the warehouse" to "launching a new product".
II. 8D and 5C: The "Standard Problem-Solving Process" from Complexity to Simplification
When encountering quality problems, a standardized process is needed to avoid "impulsive decision-making". The 8D and 5C are the two most commonly used frameworks:
1. 8D: A "Comprehensive Process Guide" for Teams to Solve Complex Problems
8D is the standard step for cross-functional teams to solve major problems. The core is "using processes to ensure that no link is omitted":
D0 (Preparation): Confirm the authenticity of the problem—verify the problem actually exists with data. For example, the defective rate of the product has increased from 2% to 8% in the past week instead of someone says the quality is poor.
D1 (Form a Group): Integrate "cross-functional resources" - for example, form a team consisting of personnel from production, R & D, quality control, and procurement to avoid the limitations of a single - department perspective.
D2 (Problem description): Use the "5W2H" method to precisely define the problem. For example, "From March 1st to 7th, 2024, among the 1,000 products produced by Production Line A, 80 had surface scratches, with a defect rate of 8%", rather than "The products have scratches".
D3 (Temporary Containment): Prevent the "spread" of the problem. For example, "Suspend the shipment of products from Production Line A and re - check all of them" to avoid defective products reaching customers.
D4 (Find the root cause): Use tools to dig deep into the "root cause". For example, use a fishbone diagram to analyze the causes of "surface scratches". Is it because the hardness of the raw materials is insufficient? Or is it because the equipment pressure is too high? Instead of finger-pointing at superficial causes such as "improper operation by workers".
D5 (Permanent Countermeasure): Solve the root problem – for example, increase the hardness of raw materials from HRC20 to HRC30 instead of remind workers to be careful.
D6 (Verification of countermeasures): Confirm that the countermeasure is effective — for example, After adjusting the raw materials, the defect rate has dropped below 1% for 3 consecutive days.
D7 (Prevent recurrence): Update the "process or standard" - for example, write "raw material hardness ≥ HRC30" into the procurement specification to avoid the recurrence of the problem.
D8 (Case Closure): Summarize the "lessons learned" - for example, "Verify the hardness first when purchasing new raw materials next time", and celebrate the team's problem-solving.
2. 5C: DELL's simplified "Rapid Problem-Solving Framework"
5C is the lightweight version of 8D, suitable for solving routine and repetitive problems. The core is to standardize the problem-solving process with five Cs:
Correct (Accurate): Describe problems with data, for example, The defect rate is 8% instead of There are many defects.
Clear: Explain in simple language and avoid confusion caused by professional terms.
Concise: Only present necessary information. For example, say "The problem is surface scratches" instead of talking about "the history of the production line."
Complete: Include "steps to reproduce the problem", such as "Scratches appear when the device pressure is adjusted to 5 bar."
Consistent: Write in a unified format. For example, "All 5C reports include 'Problem - Cause - Countermeasure'."
The essence of 8D and 5C is to use processes to transform "random problem - solving" into "controllable closed - loop management" — no matter who solves the problems, they can follow the steps to avoid omitting key links.
III. The old seven QC tools: Decode "production quality problems" with data and graphics
The old seven QC tools are the "data visualization tools" at the production site, which can help you transform "hidden quality problems" into "visible graphs or data" and are suitable for solving specific production problems.
1. Fishbone Diagram (Ishikawa Diagram): The Visual Map of Cause-and-Effect Analysis
Write the problem in the fish head and the possible causes (people, machines, materials, methods, and environment) on the fish bones. Then break down the sub - causes layer by layer. For example, the reasons for scratches on the product surface could be People: Workers didn't wear gloves, Machine: Equipment nozzles are clogged, Material: The raw material hardness is insufficient, which helps you find the root cause.
2. Stratification method: The difference detector for classified statistics
Split the data by "dimensions" (such as department, time, equipment) to find the differences. For example, "The defect rate of production line A is 5%, while that of production line B is 2%", which indicates that there is a problem with line A.
3. Pareto Chart: The 80/20 Tool for Focusing on Key Points
Use a bar chart to display the "number of problems" and a line chart to display the "cumulative percentage" - for example, "surface scratches account for 60% of the defects, and dimensional deviations account for 20%". Solving the scratch problem first can resolve 80% of the defects.
4. Check sheet: The "standardized template" for data collection
Design a form to record "key data", such as "inspect 10 products per hour and record the types of defects", to avoid missing information or chaotic records.
5. Scatter plot: The "scatter plot" for observing "correlation"
Use the horizontal axis and the vertical axis to represent two variables (such as "temperature" and "defective rate"), and observe the distribution of points. If the points show an "upward trend", it indicates that the higher the temperature, the higher the defective rate.
6. Histogram: A "bar chart" for viewing "data distribution"
Use columns to represent the "data intervals" (for example, "how many products have a size of 10±0.1mm"), which helps you understand the "process stability". If the histogram shows a "normal distribution", it indicates that the process is stable; if it shows a "skewed distribution", it indicates an abnormality.
7. Control Chart: The Early Warning Device for Monitoring Abnormalities
Use "center line (mean)", "upper control limit (UCL)", and "lower control limit (LCL)" to represent the "normal fluctuation range" of the process. If a point goes beyond the control limits, it indicates an abnormality (such as equipment failure) and requires immediate handling.
The essence of the old seven tools is to transform "judgment based on experience" into "decision - making based on facts" with "data + graphics". After all, the problems in the production site are "data problems". Visualizing the data can quickly lead to the answers.
IV. The new seven QC tools: Management thinking tools for dealing with "complex problems"
The new seven QC tools are the "decision-making tools" for middle and senior management, suitable for solving "more abstract and complex management problems" (such as process optimization and project planning). The core is to "integrate scattered information and find the key logic":
1. Relationship diagram method: A "network map" for handling "complex associations"
Connect "problems" with "factors" using lines to show their "interactions" — for example, "customer complaints" may be related to "production delays", "poor quality", and "poor service attitude", which helps you find the "core factors".
2. KJ Method (Affinity Diagram Method): A "Brainstorming Tool" for Integrating "Scattered Opinions"
Collect the team's "ideas" using cards and then categorize and summarize them. For example, ideas on "how to improve customer satisfaction" may be grouped into three categories: "product quality", "service speed", and "after-sales support", which helps you integrate consensus.
3. System diagram method (tree diagram method): A "decomposition tool" that unfolds the "goal" layer by layer
Break the "big goal" into "sub - goals" and then into "actions". For example, "Improve product quality" → "Improve raw material quality" → "Select higher - quality suppliers" → "Formulate supplier evaluation criteria", which helps you turn your goals into reality.
4. Matrix diagram method: The cross table for multi-dimensional analysis
Use "rows" and "columns" to represent two dimensions (such as "product characteristics" and "process parameters"), and examine their "corresponding relationships" — for example, "product hardness" corresponds to "heat treatment temperature" and "holding time" to help you find the optimal combination.
5. Matrix data analysis method: A "statistical tool" for quantifying "matrix relationships"
Process matrix data using statistical methods (such as regression analysis) to calculate the "correlation of variables" - for example, "for every 10°C increase in heat treatment temperature, the hardness increases by 5 HRC", which helps you make quantitative decisions.
6. PDPC method (Process Decision Program Chart): A "pre - plan tool" for predicting "risks"
Draw the "project process" as "steps + risks + countermeasures" — for example, in the process of "mass production of new products", for the risk of "delayed procurement of raw materials", the countermeasure is to "find alternative suppliers", which helps you deal with risks in advance.
7. Network Diagram Method (PERT/Critical Path Method): A time tool for planning project schedule
Use arrows to represent "tasks" and nodes to represent "milestones" to find the "critical path" (the longest task chain). For example, the critical path of "new product development" is "design → proofing → testing → mass production", which helps you optimize time and avoid delays.
The essence of the New Seven Management and Planning Tools is to use "structured thinking" to handle "complex and abstract management problems" - when a problem involves multiple departments and multiple factors, these tools will help you sort out the logic and find the key points.
V. Five Core Manuals of ISO/TS16949: The "Full Link of Quality Assurance" in the Automotive Industry
ISO/TS16949 is the quality management system standard for the automotive industry. The five core manuals are its "implementation tools", covering the entire process from "product design" to "mass production" to ensure the consistency of product quality.
1. APQP (Advanced Product Quality Planning): "Full - process planning" from "design to mass production"
Help you plan in advance "quality objectives, processes, and resources" during "new product development" – for example, "verify the 'product hardness' in the design stage and verify the 'process capability' in the trial production stage" to avoid problems during mass production.
2. FMEA (Potential Failure Mode and Effects Analysis): Early warning for risk prevention
Before "design or production", identify "potential failure modes" (such as "part breakage") and "consequences" (such as "vehicle breakdown"), and formulate "preventive measures" (such as "increase the thickness of the part") to avoid problems.
3. MSA (Measurement System Analysis): Ensure the "reliability" of "measurement data"
Verify the accuracy of the "measuring tools" and "measuring methods" - for example, "the error of the vernier caliper is ±0.01mm", and ensure that the "measurement results" can reflect the "true quality".
4. SPC (Statistical Process Control): Monitor the "stability" of the "production process"
Use control charts to monitor "process fluctuations" - for example, "inspect 10 products per hour and record their dimensions". If a point goes beyond the control limits, it indicates that the process is abnormal and needs adjustment.
5. PPAP (Production Part Approval Process): The final verification before mass production
Ensure that the "production parts" meet the "design requirements" - for example, "the dimensions and performance of mass - produced parts are the same as those of the sample parts" - before starting mass production.
The essence of the five major manuals is the "quality assurance closed-loop" in the automotive industry. From "design" to "mass production", every step is verified with tools to ensure the stability and reliability of "product quality".
VI. 10S and the Five Constant Principles: The Underlying Logic from "Environmental Management" to "Quality Awareness"
10S and the 5S Methodology are the "foundation project" of quality management. Through "environmental organization", "quality awareness" is cultivated, enabling employees to change from "passive compliance" to "active maintenance".
1. 10S: "Full-dimensional environmental management" extended from "5S"
Sorting (SEIRI): Throw away "unnecessary items" - such as expired raw materials in the warehouse.
SEITON: Designate a specific location for items, for example, "Tools are placed in the second drawer on the right side of the production line", and the items can be found within 30 seconds.
Cleaning (SEISO): Clean the "production environment" - for example, clean the equipment every day to avoid defects caused by dust.
Cleaning (SEIKETSU): Standardize "Sorting, Straightening, and Sweeping" - for example, "Conduct a comprehensive cleaning every Friday afternoon."
Shitsuke: Cultivate the habit of following rules — for example, workers operate with gloves on.
Safety (SAFETY): Eliminate "potential safety hazards" - such as "installing guardrails on equipment".
Saving: Reduce "waste" - such as "recycling scraps".
Service (SERVICE): Improve "internal service" - for example, "the warehouse delivers materials to the production line in a timely manner".
Satisfaction: Achieve customer and employee satisfaction — for example, low product defect rate leads to customer satisfaction; clean environment results in employee satisfaction.
PERSISTENCE: Continuously "maintain 10S" - avoid "a three - minute enthusiasm".
2. Five Constant Principles: Daily management of the simplified 10S
Regular organization: Regularly clean up "unnecessary items" - for example, organize the warehouse once a month.
Regular straightening: "Fixed-location management" of items - for example, "Put documents in folders and label them with names."
Regular cleaning: Define "hygiene responsibilities" - for example, "Zhang San is responsible for cleaning Production Line A".
Regular standardization: Make "management visible" - for example, "use color labels to distinguish 'qualified' and 'unqualified' products".
Practice self - discipline regularly: Practice the "Five - S Method" every day, such as "organizing tools before getting off work".
The essence of 10S and the Five S's is to cultivate "quality awareness" through "environmental management" — when employees get used to a "tidy and orderly" environment, they will naturally pay more attention to "details" and reduce quality problems caused by "chaos".
VII. Eight Criteria for Judging Abnormalities in SPC: Use "Statistical Rules" to Monitor "Process Stability"
The core of SPC (Statistical Process Control) is to "distinguish between normal fluctuations and abnormal fluctuations". The eight criteria for judging abnormalities are its "judgment standards", which help you quickly identify "process abnormalities":
1. 2/3A: Among 3 consecutive points, 2 points are in "Zone A on the same side of the center line" (close to the control limit) – indicating that the process has a "drift trend".
2. 4/5C: Among 5 consecutive points, 4 points are outside the C zone on the same side of the center line - indicating that the process has a "slight deviation".
3.6 Runs of 6 points: Six consecutive points showing an "increasing or decreasing" trend - indicating a "continuous shift" in the process (e.g., equipment wear).
4.8 Lack of C: There are 8 consecutive points "on both sides of the center line, but no points in the C zone", which indicates that the process "has excessive fluctuations" (for example, the raw materials are unstable).
5.9 One-sided: 9 consecutive points "on the same side of the center line" - indicating a "mean shift" in the process (e.g., incorrect adjustment of equipment parameters).
6.14 Alternation: "Alternation of adjacent points up and down" at 14 consecutive points - indicating that the process "has periodic fluctuations" (such as differences between shifts).
7.15 All C: 15 consecutive points "above and below the center line of the C zone" – indicating that the "process fluctuation is too small" (e.g., the measuring tool is ineffective).
The essence of the SPC rules for identifying abnormal situations is to replace "empirical judgment" with "statistical laws". No matter who monitors the process, they can identify abnormalities according to the rules, avoiding "false negatives" or "false positives".
The "underlying logic" of quality tools
At the core of all quality tools lies "structured thinking" - breaking down "vague problems" into "analyzable modules" and integrating "scattered information" into "decision - making logic".
- If you want to implement a "task on the ground", use the 5W3H method.
- If you want to "solve problems", use the 8D or 5C method.
- If you want to "analyze production problems", use the old seven tools.
- If you want to "handle management problems", use the new seven management tools.
- If you want to "ensure the quality of automotive products", use the five major manuals.
- If you want to "cultivate quality awareness", use the 10S method or the Five Constant Principles method.
- If you want to "monitor the process", use SPC.
I. Abnormal Patterns of Control Charts and Logic for Determining Stability
Control charts determine process stability based on the position, trend, and distribution of points. The core rules need to be understood in conjunction with the "area definition" (Area A: high-risk area near the control line; Area C: low-risk area near the center line):
2 or 3 Points Falling in Area A: If 2 or 3 consecutive points enter Area A, it indicates that the process fluctuation has reached the critical value (e.g., equipment parameter deviation), and immediate troubleshooting is required.
4 or 5 points falling in Area C: Consecutively having 4 or 5 points concentrated in Area C indicates that the fluctuation is abnormally narrowed (such as over - adjusting the machine), which is likely to trigger subsequent fluctuations.
Six consecutive increasing/decreasing points (a consecutive string): Six consecutive points show a linear trend (e.g., the temperature gradually rises, the size gradually increases), indicating the existence of a systematic drift (e.g., tool wear), which requires intervention.
C missing at 8 points: All 8 points are in Area A/B (no points in Area C), indicating scattered fluctuations (such as large differences in raw material batches) and an out-of-control process.
15 points all in C: 15 points are densely concentrated in area C, indicating that the data may be "fabricated" or the detection accuracy is insufficient (e.g., the measuring tool is not calibrated).
Alternating rotation at 14:00: The value at 14:00 alternates in a "high - low - high" pattern (such as parameter fluctuations caused by shift rotations), and periodic interference needs to be eliminated.
9 o'clock unilateral + out-of-bounds: The 9 points are concentrated on the same side of the center line, and the 1 point is outside Area A (out-of-bounds), indicating that the process has "deviated" (e.g., incorrect raw material formula).
The underlying logic of the principle for judging stability is "allowing small - probability random fluctuations":
- All 25 consecutive points are within the control limits: The process is completely stable (no abnormalities).
- For a series of 35 data points, at most 1 point is out of bounds: One point out of bounds is considered a "random error" (probability ≈ 0.27%), which does not affect the overall stability.
- For every consecutive 100 data points, a maximum of 2 points going out of bounds: Having 2 points out of bounds is still within the acceptable range (probability ≈ 0.5%). If the number exceeds this, a root - cause investigation is required.
II. ISO9000: Ensure Quality Consistency with a Systematic Approach
The core of ISO9000 is "transforming quality from 'experience' into 'replicable processes'", and its characteristics can be broken down into "112 344 568".
One essence: Consistency among speaking, writing, and doing. The "quality commitment" for external publicity (speaking), the "system documents" internally (writing), and the actual "operation and execution" (doing) must be consistent. For example, if it is claimed that "100% inspection" is carried out, there should be a "Finished Product Inspection Procedure", and in reality, each product should be inspected in accordance with the procedure.
1 center: Centered around customers. The starting point of all activities is "understanding customer needs" (e.g., customers require "12 - hour battery life"), and the end - point is "meeting the needs" (e.g., optimizing battery capacity). Quality that is divorced from customer needs is "self - indulgent quality".
Two basic points: Customer satisfaction + Continuous improvement. Customer satisfaction is the result (achieved through products/services), and continuous improvement is the means (optimizing processes through the PDCA cycle). For example, a restaurant adjusts its dishes (improvement) based on customer feedback to enhance satisfaction.
Three types of characteristics:
- Suitability: The system should "be suitable for the enterprise scale" (small factories do not need to copy the complex processes of large groups).
- Sufficiency: The system should "cover all links" (control requirements are applicable to R & D, procurement, production, and after - sales services).
- Effectiveness: The system should be "practically useful" (not just "window - dressing documents", but capable of solving the problem of "high defective rate").
Four "Whatever"s:
- Everything should have someone in charge (clarify "who is responsible for procurement and who is responsible for inspection").
- Everything should follow regulations (procurement follows the "Supplier Selection Process", and inspection follows the "Sampling Standard").
- Ensure that everything can be verified (keep procurement records and inspection reports to prove that "it has been done").
- Everything is supervised by someone (check whether it is done according to the process through internal audits).
Four major products: Cover all output forms - services (express delivery), software (APP), hardware (mobile phones), and process materials (steel, paint).
Five major modules: The "full - process framework" of quality management ——
1. Quality management system (General outline, clarifying the scope and requirements);
2. Management responsibilities (Leadership sets the policy and allocates resources);
3. Resource management (managing personnel, machines, materials, methods, and the environment);
4. Product realization (the entire process from order to delivery);
5. Measurement, analysis, and improvement (Use data to identify problems and improve processes).
Six mandatory documents: The "basic procedures" required by ISO 9000:2000
Document control (managing the compilation, review, and distribution of documents), Quality records (retaining evidence), Internal audit (checking the implementation of the system), Non - conforming product control (managing defective products), Corrective measures (solving the problems that have occurred), Preventive measures (preventing problems from occurring).
Eight principles: The "fundamental values" of quality management ——
Customer focus, leadership (the boss should attach importance), full participation of all employees (front-line employees know the problems best), process approach (break down and optimize the process), systematic management (not just treat the symptoms), continuous improvement (keep moving forward), fact-based decision making (make decisions based on data), and mutual benefit with suppliers (suppliers are partners).
III. Seven Techniques of IE: Eliminate Waste Scientifically
The core of IE (Industrial Engineering) is "to do the right things at the lowest cost", and the seven techniques focus on "process optimization".
Procedure analysis: Draw a "flowchart" (e.g., procurement → warehousing → production → delivery) and delete "redundant steps" (e.g., unnecessary approvals).
Time analysis: Measure the "standard time" (e.g., it takes 3 minutes to assemble 1 part), which is used to calculate production capacity and formulate plans.
Action analysis: Break down "operational actions" (e.g., pick up tools → tighten screws → put down tools), and eliminate "ineffective actions" (e.g., frequently turning around to get materials).
Assembly line analysis: Adjust the "takt time" (the time for each workstation) and resolve the "bottlenecks" (for example, a slow workstation causes a backlog downstream).
Operation analysis: Calculate the "equipment utilization rate" (actual operating time / available time) and find out the reasons for downtime (such as breakdowns, waiting for materials).
Material analysis: Optimize the "handling route" (e.g., the distance from the warehouse to the production line) and reduce "handling waste".
Environmental analysis: Adjust the "working environment" (such as lighting, temperature, layout) to improve efficiency (for example, dim light in the workshop will increase the error rate).
IV. Common surface treatments: Balancing functionality and appearance
The goal of surface treatment is "enhancing performance (rust prevention, wear resistance) + improving appearance". Common types and applications:
Grinding (polishing): Remove burrs and scratches to make the surface smooth (e.g., pre-treatment of metal parts).
Electroplating: Plating with metals (chromium, nickel) for rust prevention and aesthetic purposes (such as faucets, auto parts).
Spraying/baking finish: Spray paint and bake for protection and decoration (e.g., the outer shells of household appliances).
Heat treatment: Alter the material properties through heating and cooling (e.g., quenching gears to increase hardness).
PVD (Physical Vapor Deposition): Vacuum deposition of thin films (titanium, zirconium), wear-resistant and with uniform color (such as the "iridescent coating" on the middle frame of mobile phones).
Sandblasting: High-pressure sand particles impact the surface to make it rough (to increase the adhesion of the coating, such as for automobile hubs).
Lathing patterns: Spiral/annular patterns produced by lathe machining (such as the decoration on watch cases).
Rubbing grain (brushing): Use an abrasive belt to create parallel grains (such as the "metal brushing" on the laptop shell).
Oxidation (coloring): Anodize the aluminum alloy to form a colored oxide film (e.g., the back cover of a mobile phone).
Matte finish: Reduce gloss (e.g., the "satin finish" of home appliance panels to avoid reflection).
Blackening: Chemical treatment (blackening, phosphating) for low - key anti - rust purposes (e.g., screws, knives).
Edge trimming: Trim the rough edges (such as those of plastic parts) to make the edges smooth.
Engraving: Use a tool to carve delicate patterns (e.g., decoration on jewelry and mobile phone buttons).
V. 10 Steps to RoHS Compliance: Full-chain Control of Hazardous Substances
The core of RoHS (Restriction of 6 substances such as lead and cadmium in electrical and electronic equipment) is "full supply chain control from the source to the end", and the 10-step process is "a feasible compliance path":
1. Determine the degree of relevance: First, judge whether the product falls within the scope of RoHS (for example, mobile phones do, while furniture does not) to avoid unnecessary work.
2. Form a cross - departmental team: RoHS involves procurement (responsible for raw materials), production (responsible for processes), and quality control (responsible for testing), which requires cross - departmental collaboration.
3. Issue a compliance statement: Promise externally that "the products comply with RoHS" (e.g., mark it on the official website) to build customer trust.
4. Prepare an implementation plan: clarify "who does what and when" (e.g., complete the supply chain assessment within 3 months).
5. Evaluate supply chain associations: Raw materials are crucial for RoHS compliance (e.g., plastics containing lead, solder containing cadmium). It is necessary to determine whether the supplier's materials are compliant.
6. Select eligible suppliers: Give priority to suppliers with "RoHS certification" or those who "can provide material statements" to control risks at the source.
7. Establish a supply chain declaration procedure: Require suppliers to provide a "material composition declaration" (e.g., "This plastic does not contain lead") and keep evidence of compliance.
8. Limited testing + verification: Test key materials (such as solder, plastics) and verify the authenticity of suppliers' declarations (e.g., measure heavy metals using ICP-MS).
9. Change customer information: Provide test reports and declarations to customers to meet their procurement requirements (e.g., Apple requires suppliers to provide RoHS certificates).
10. Integrate overall operation: Incorporate RoHS into daily processes (e.g., add RoHS clauses to procurement contracts and give priority to compliant materials in R & D) to maintain continuous compliance.