Workplaces and agencies that operate breathalyzers often keep a calibration certificate for each device. A calibration certificate is a document showing what calibration work was done on a specific breathalyzer and when. Calibration here means the work of establishing the relationship between a standard and the values the device displays. Its role differs from a manual that explains how to use a product or transaction records that show a purchase.
While preparing audit or assessment materials, or rechecking documents submitted outside in the past, you may not be able to find a certificate file. What you need to do then is not create a new certificate, but work out which calibration of which device the lost document relates to and ask the issuing body whether a copy or reissue is possible. Recovering a document must be kept separate from a new calibration and from verification that judges whether a device meets requirements after repair.
First define the scope of the certificate to find
If the same breathalyzer has been calibrated several times, there may be a separate certificate for each calibration date. Start by sorting out whether you need the most recent document, the document submitted in a particular year, or all documents for a particular device. If an outside body requested the material, confirming the device and period requested makes clear the scope of the lookup to pass to the issuing body.
Losing a certificate does not by itself create a reason to recalibrate the device right away. Getting a copy of a past certificate is a procedure for recovering the document of a past calibration. A new calibration, by contrast, is work that establishes the relationship between the device's indication and the standard at that point in time, and receiving a copy does not replace a new calibration or verification.
Gather the device and clues from the original submission
Whether copies are provided, the scope of stored records, and how to request them may differ according to the procedures of the body that issued the certificate. So it is best to gather the facts confirmed from the markings on the device and from internal documents before making the request. Even if you do not have every piece of information, you can send the items you have confirmed first and supplement any additional material needed according to the issuing body's guidance.
| Material to prepare | What to look for | Why it is needed |
|---|---|---|
| Breathalyzer unit | Model name and serial number | To identify the device the document covers |
| Equipment management log | Calibration date, issuing body, submission number | To narrow down the needed round among several calibrations |
| Emails, submission, and billing records | Document number, submission date, department in charge at the time | To add lookup clues beyond the serial number |
| Purpose of the document request | Internal records, checking documents submitted in the past, etc. | To explain the scope of the documents needed and how they should be delivered |
Even if the serial number is not visible, you must not write in the number of another device that looks similar. If you receive the document for the wrong device, the calibration histories of individual devices can become mixed up later. If you find an attachment in old emails, do not rely on the file name alone. Check that the serial number, calibration date, and document number inside the document match the device and round you are looking for.
Put together the request in a hypothetical case
Suppose, for example, that a safety manager preparing for an assessment cannot find the certificate for a breathalyzer calibrated in 2024. The equipment management log says it was calibrated in June 2024, and the model name and serial number can be confirmed on the device itself. No certificate file remains in the shared document folder or in the email of the person in charge at the time.
What this observation tells you is that although the file is missing, you have device identification and time clues to ask the issuing body to look up. This alone does not let you conclude that the body has definitely kept the record or will provide a copy. A possible action is to put together the device serial number, the calibration date in the log, when it was submitted or billed at the time, and the purpose for which the document is needed, and send them, supplementing as needed if the body asks for a document number or proof of authority to request it.
The completion criterion is not simply receiving a file. You must check that the serial number on the document you receive matches the device, that the calibration date matches the round you were looking for, and that the document number and pages are complete. If these conditions are met, you can record that the document for that calibration of that device has been recovered.
Record the copy receipt date separately from the calibration date
Even if the issuing body provides a copy or reissued document of a past certificate, the date you received the document again is not the actual calibration date. For example, if the device was calibrated in June 2024 and you received a copy in March 2025, keep the calibration date in the equipment management log as June 2024. Keeping the copy receipt date and the file's storage location in a separate note prevents the meanings of the two dates from getting mixed.
Submitting a product manual or general specification sheet in place of a certificate is also not appropriate. A manual contains how to use the product and general information, while a certificate identifies an individual device and an individual calibration. If only screen captures or some pages remain, also check whether the full document is needed and whether any pages are missing.
Decide on a storage method that prevents the next loss
After recovering the document, you can store it in a folder for each device using the serial number and calibration date, and link the document number or storage location in the equipment management log. If files are kept only in a staff member's personal email or PC, they are hard to find again when the person in charge changes, the PC is replaced, or the mailbox is cleaned up. Keeping them in a shared document folder where the necessary staff can find them and access rights are managed reduces confusion in practice.
If another document has already been shared by mistake as the certificate, it is best to announce the correct document's storage location and the device it applies to at the same time. If there is a deadline for external submission, you can tell the issuing body when you need it, but you must not set the lookup and document delivery schedule on your own. Even if the record cannot be found, keeping the device information you have, the date of your request, and the issuing body's reply lets you keep the process of recovering past documents separate from later equipment management actions.
