According to the requirements of metrological certification and laboratory accreditation, ensuring the accuracy, reliability, and scientific nature of test results is crucial. It's essential to record all relevant data during testing, including sufficient information to identify factors affecting measurement uncertainty. This helps ensure that tests can be reproduced under similar conditions and maintains traceability in measurements. Therefore, it's necessary to discuss the format and content of original records and standardize them for most primary laboratories. This will lay a solid foundation for future laboratory accreditation.
1
Main Content and Requirements of Original Records
a Basic Information
A.1 Title: Detection organization and type of original record.
A.2 Sample name and properties: For product samples, use the trade name; for non-product samples, specify the exact name (e.g., gas, water, catering, or suspected poison samples collected on-site).
A.3 Sample number: Assigned by the sample acceptance or quality control department. Must be fully coded and unique for identification.
A.4 Test item: The specific name of the item being tested.
A.5 Test method: Prefer international, regional, or national standards. If not available, use the book title and method name, specifying the exact entry.
A.6 Test start and end dates: These are critical for the validity of the results.
A.7 Instrument details: Include model, name, factory number (unique identifier), and usage conditions (e.g., temperature, wavelength, etc.).
A.8 Environmental conditions: Indicate temperature, humidity, or any factors directly influencing the test results.
A.9 Reference materials: Provide source, grade, validity period, and expiration date of the reference material used for quality control.
A.10 Standard solutions: For spectrophotometry, include name, source, concentration, set value, and expiration date. For titration, indicate name, calibrated concentration, and calibration date.
A.11 Calculation formula: The final formula used for analysis.
A.12 Signatures: The person conducting the test must be a qualified professional or trained long-term contractor.
A.13 Review: Data and processing must be checked and signed by a responsible professional.
A.14 Page count: Record the page number and total pages to ensure completeness of the original record.
b Test Data
B.1 Relevant data: Include sample amount, dilution factor, air sampling volume, conversion factor, instrument components, reagents, and experimental conditions.
B.2 Measured data:
(1) Spectrophotometry: Record standard curve range, absorbance values, and parameters a, b, r. Also note blank and sample absorbance, and calculate sample concentration or mass.
(2) Titration: Note initial and final titrant values for blanks and samples, and the total consumption.
(3) Gravimetric method: Record constant weight of the vessel before and after baking or burning.
(4) Instrument method: Include quantitative curves, blank, and sample responses. Qualify all data (e.g., retention time, peak area).
(5) Sensory test: Describe observations (color, smell, taste, etc.) and draw conclusions.
(6) Visual limit test: Record observed phenomena and limit concentrations.
(7) Toxicity test: Document all phenomena and confirm positive samples with additional methods.
(8) Results from calculation formulas.
(9) Final test results.
B.3 Original record writing rules:
Records must be filled in with pens or carbon pens. Pencils or ballpoint pens are not allowed. If errors occur, strike through the incorrect text with a double line, write the correct information above, and sign the correction.
2
Several Elements to Be Reflected in the Original Record
2.1 Measurement Traceability
2.1a Use legal units of measure.
2.1b For reference materials, record their purchase date, level, and traceability to SI units or certified references. Self-prepared standards should be traceable to the source or purchased as certified solutions.
2.1c For equipment, record unique identifiers to check if they are calibrated by a metrology department.
2.2 Quality Control
Include quality control measures and data throughout the testing process.
2.2a Select appropriate analytical methods based on national standards or authoritative international methods.
2.2b Blank data: Include reagent or sample blanks. Blanks affect accuracy, especially at low concentrations.
2.2c Calibration curve: Draw it for each batch, report regression equation and correlation coefficient. Sample concentration must fall within the curve range.
2.2d Parallel samples: Reduce random error. At least 10–20% of samples should be measured in parallel.
2.2e Internal QC: Periodically use certified reference materials for quality checks.
2.2f Spike recovery: Include in each batch. Ensure spike recovery does not exceed method limits.
2.2g Critical data: When values approach control limits, increase measurements to observe trends before judgment.
2.3 Unqualified Samples
Unqualified samples should be retested using the same or different methods. Collect corroborating data to support findings.
3
Expression of Analysis Results
3.1 Valid Number of Digits in Reported Results
Determine based on significant figures of data, such as sample size, standard solution concentration, instrument accuracy, and measurement sensitivity. Do not arbitrarily increase or decrease digits. Follow GB/T 8170 or specific standards for calculations.
3.2 Parallel Sample Results
Report the average of parallel measurements. Ensure the number of significant digits meets hygiene standards.
3.3 Selection of Suspicious Data
Record suspicious data truthfully. If not due to systematic error, apply statistical tests and decide accordingly.
3.4 Results Report
If below detection limit, report as “not detected†and state the detection limit. Ensure method sensitivity meets hygiene standards. If unit differs, follow the standard’s requirement. In some cases, report as “negative,†“qualified,†or “not detected†based on background.
3.5 Uncertainty Report
If the result is near the critical value, include uncertainty data. If the recognized method already specifies uncertainty, no further action is needed.
To better assist lab technicians with daily records, please add the official account and share this post. Send a screenshot to the "Detector" WeChat account and leave your contact info to receive the original record set.
"Instrument use log *2 + solvent label stickers *50 + instrument maintenance log *1" original record package
Friends, easy to forward, small gifts await you!
Receive a gift?
1. Add the Detector WeChat public account
2. Send the keyword "private cheats" and send
3. Click to enter the article
?
4. Click the "..." in the top right and select "Share to circle"
?5. Click to send
Friends, easy to forward, small gifts lead ~
Digital Multimeter ,Bench Type Digital Multimeter,Meco Multimeter,Hioki Multimeter
YINTE TOOLS (NINGBO) CO., LTD , https://www.yinte-tools.com