What to check first on your certificate
Start with the basics on the certificate before you file it away or send it to a customer. The instrument description, model, serial number, date of calibration and the certificate number should all match the item you submitted. If one of those details is wrong, it can cause trouble during audits, quality checks or client sign-off.
At our calibration lab in Isando, Kempton Park, we see this often with calipers, micrometers, gauges and multimeters that move between departments. A certificate only helps if it can be linked to the right tool, so it is worth checking every line while the instrument is still at hand.
- Confirm the instrument type and range
- Check the serial number exactly as marked on the tool
- Review the calibration date and due date
- Make sure the certificate number is clear and readable
Understanding serial numbers and traceability
The serial number is the key link between the physical instrument and the result on the page. On some tools it is engraved clearly, on others it may be lightly marked or partly worn from use in factory conditions. If the number is missing, faded or duplicated on more than one item, traceability can become a problem.
We recommend that customers record serial numbers before sending items for calibration, especially when several similar instruments are used in the same workshop or plant. A simple asset list helps, and it can save time later if there is a query from procurement, QA or a customer site in Germiston, Boksburg or Midrand.
- Use one asset number per instrument, not per batch
- Keep a photo of the serial plate where possible
- Note any prefixes, letters or special marks
- Check that the certificate and instrument show the same identifier
How to read result remarks and measurements
The result section shows what was measured and whether each point met the required tolerance. For example, a micrometer may be checked at several points across its range, while a pressure gauge or temperature instrument will show results at specific reference points. The remarks may say pass, fail, as found, as left or out of tolerance, depending on the job and the item.
Pass means the reading fell within the stated limit. Fail or out of tolerance means at least one point did not meet the requirement. As found records the instrument condition before adjustment, while as left shows the final state after any correction. If a result is unclear, ask for the tolerance used so you can compare it against your own specification sheet.
- Look at the tolerance limit, not only the reading
- Check whether the result is as found or as left
- Review all test points, not just the first line
- If needed, compare the certificate to your internal spec
When a certificate needs a correction
Sometimes a certificate needs updating because of a typo, a missing serial number, a wrong department reference or a client order number that was entered incorrectly. These issues are usually sorted quickly if you report them with the certificate number and the correct details. It helps to contact us as soon as the problem is noticed, rather than waiting until month-end filing or a customer audit.
If a tool was damaged in transit, exposed to moisture on a coastal job, or used after a power dip at a production site, let us know that too. Conditions like that can affect the reading or explain why a follow-up check is needed. A clear note from the field saves back-and-forth later on.
- Send the certificate number and instrument serial number
- Highlight the exact line that needs correction
- Attach supporting details from your receiving record
- Tell us if the item was used again after calibration
Using certificates for audits and customer records
Most South African businesses keep calibration certificates for audit trails, supplier approvals and internal quality systems. The certificate should show enough detail for an auditor to follow the instrument history without guesswork. That includes the measurement points, result remarks, traceability references and the status of the item at the time of testing.
It is also useful to store certificates with the correct department or line reference. For example, a gauge used in assembly should not be filed with test equipment from maintenance. Good record keeping makes it easier to prove compliance when inspectors ask for proof of control, whether your site is in Isando, Edenvale or Jet Park.
- File certificates by asset number or location
- Keep old and current certificates together for comparison
- Match the certificate to the correct department or line
- Retain any repair or adjustment notes with the record
Sending items in for recalibration or review
If you are unsure about a certificate or believe the instrument may no longer be within spec, send it in for a fresh check. Our courier collection service covers Johannesburg and nationwide, which helps when workshops are busy or when travel time cuts into production. We handle caliper calibration, micrometer calibration, gauge calibration and other common instrument types for businesses that need dependable records.
Before collection, clean the instrument, pack it securely and include any site notes that may affect the result. That might be wear, damage, contamination or a special operating condition. Clear instructions help our team issue the right certificate and keep your records in order. If you are based in Kempton Park, Meadowdale or nearby, this is often the quickest way to sort the job without taking staff off site.
- Remove loose dirt, oil or residue before packing
- Include the job card or purchase reference if available
- State any urgent turnaround needs up front
- Tell us if the item is part of a critical production process
