In brief
You can check whether an OSGB is authorised, without logging in, from the List of Authorised OSGBs and TSMBs on the ISG-KATİP home page. The authorisation certificate is specific to the address and trade name and is renewed every five years; the certificate of an OSGB that does not apply for renewal on time is suspended. The employer is responsible for ensuring that the OSGB it obtains services from is assigned with a valid authorisation certificate; an assignment by a suspended OSGB may make you appear to have no specialist or physician in an inspection.
Why is checking an OSGB’s authorisation certificate the employer’s job?
When signing a contract with an OSGB (joint health and safety unit), most employers look at the price, the visit pattern and the specialist’s experience; they do not ask whether the organisation’s authorisation certificate is valid. Yet Art. 5/7 of the Regulation on Occupational Health and Safety Services is clear: the employer is responsible for ensuring that the OSGBs it obtains services from are assigned with a valid authorisation certificate. That is why checking an OSGB’s authorisation certificate is not something to do once before the contract and forget, but a check to repeat at least once a year and around renewal dates.
Under the regulation, the authorisation certificate is issued exclusively for the address and trade name stated in the application file (Art. 17/2). An OSGB cannot operate without an authorisation certificate or without completing the renewal process on time (Art. 17/4). The service area is also limited: an OSGB can provide services in the province where it is established and in the provinces bordering it (Art. 12/5). For a workplace in Bursa, this means the address on the authorisation certificate must be in Bursa, Yalova, Kocaeli, Sakarya, Bilecik, Kütahya or Balıkesir.
For a general definition of an OSGB and its staffing requirements, see our article what is an OSGB. This article focuses only on how to check the validity of the certificate.
The authorised OSGB list: the ISG-KATİP home page
The home page of ISG-KATİP (the Ministry’s online OHS registration system, isgkatip.csgb.gov.tr) offers several lists that can be accessed without logging in via e-Devlet (the government’s online services portal). As of November 2026, the page contains the following headings:
| List or tool | What is it for? |
|---|---|
| List of Authorised OSGBs and TSMBs | Checking whether the OSGB is among the authorised organisations |
| List of OSGBs Authorised for a Fixed Medical Testing Facility | Seeing whether the OSGB is authorised to carry out tests at its own address |
| List of Authorised OSGBs with a Mobile Occupational Health Vehicle | Seeing which OSGBs can provide services with a mobile vehicle |
| List of Authorised Occupational Hygiene Laboratories | Checking the authorisation of the laboratory that will carry out workplace environment measurements |
| Authorised Work Equipment Inspection Bodies | Checking the body for equipment requiring accredited inspection |
| Document Verification | Verifying the authenticity of a document generated on ISG-KATİP |
The authorised OSGB list downloads as an Excel file. Search for the OSGB by its trade name in the file and compare the information in the list with the copy of the authorisation certificate you hold. The site’s screens may change over time; if the list cannot be found, you can send your questions via ALO 170 (the Ministry’s helpline) or CİMER (the Presidential Communication Centre), as indicated on the home page.
Checking an OSGB’s authorisation certificate: step by step
- Ask for a copy of the authorisation certificate. At the quotation stage, ask for a copy of the certificate; note the trade name, address, certificate number and date of issue. This information is your record of the OSGB authorisation number.
- Check the list. Download the authorised OSGB list from the ISG-KATİP home page and search for the OSGB by its trade name.
- Check the service region. The province on the authorisation certificate must be the province where your workplace is located or one bordering it. Providing services in another province requires opening a branch there (Art. 12/5).
- Check the consistency of the trade name. OSGBs may use only the name and trade name written on the authorisation certificate on signs, printed documents and electronic media (Art. 17/5-a). The trade name on the quote, the invoice and the ISG-KATİP contract must be the same.
- Calculate the renewal date. Using the method in the section below, write the next renewal date in your file.
- Check the contract screen. In the contract that comes to you for approval on ISG-KATİP, are the OSGB’s trade name, the assigned specialist and physician and the monthly times correct? The contract is approved by both parties within five days at the latest; work cannot start with an unapproved assignment (Art. 14). For the approval steps, see our article on ISG-KATİP contract approval.
- Record the result. Note the date and result of the check in your OHS file; repeat the check at least once a year and when the renewal date approaches.
The certificates of the persons it assigns matter as much as the organisation’s authorisation. For the specialist’s class and renewal status, see our article on checking an OHS specialist’s certificate, and to see who has been assigned to your workplace, see checking assignments on ISG-KATİP.
OSGB renewal period and validity of the authorisation certificate
The authorisation certificate is renewed every five years (Art. 20/1). The OSGB applies via the e-Devlet infrastructure no more than 60 days before the five years are completed. The authorisation certificate of an OSGB that does not apply on time is suspended until the renewal process is completed; if the renewal is not completed within three months of the end of the renewal period, the certificate is cancelled outright (Art. 20/2).
The Ministry’s OSGB application guide contains two important notes on practice:
- The five-year renewal period is calculated from the date the authorisation certificate was first issued. A change of address, or time spent suspended during the five years, does not change the renewal date.
- Organisations that do not apply for renewal on time have their existing contracts cancelled and cannot enter new contracts.
Example: For an OSGB whose authorisation certificate was issued on 15 March 2022, the renewal date is 15 March 2027. The OSGB can apply for renewal on 14 January 2027 at the earliest. Write this date in your file and ask your OSGB in writing in February whether the application has been made. If the application is not made, your contract being cancelled means your workplace suddenly being left without a specialist or physician.
Suspension and cancellation: in which situations?
The OSGB’s authorisation certificate can also be suspended for reasons other than renewal. Under Art. 21 and 22 of the regulation, the main situations are as follows:
| Situation | Consequence |
|---|---|
| Warning points reaching a total of 300 | 6-month suspension |
| Documents issued under the regulation proving to be untrue | 3-month suspension |
| Providing services outside the address or provincial boundaries for which it was authorised | 6-month suspension |
| Transferring all or part of the service to another party | 6-month suspension |
| Changing address without approval, or not reporting a change of trade name within 30 days | 1-year suspension |
| Being suspended three times in one renewal period | Outright cancellation |
| Making contracts or providing services while the certificate is suspended | Outright cancellation |
OSGBs that are suspended or cancelled are notified in writing by the Directorate General, and the situation is announced on its website (Art. 22/6). In addition, under Art. 8/2 of Law No. 6331, the authorisation certificate of an OSGB that does not report a life-threatening danger to the Ministry is suspended for six months, and for one year on repetition.
The consequences of working with a suspended OSGB
The fine is not the only consequence:
- Gap in records: The validity of risk assessment revisions, training or examination records made during the suspension may become questionable.
- Accident risk: If a work accident occurs during this period, it becomes harder for the employer to show that it obtained OHS services properly. Under Art. 4 of Law No. 6331, outsourcing services does not remove the employer’s responsibility in any case.
- The OSGB’s liability: If the authorisation certificate is cancelled or suspended, the OSGB is responsible for the legal consequences arising from service and employment contracts made previously (Art. 22/7). This is the basis on which the employer can claim the loss it has suffered from the OSGB; but it does not remove the administrative fine.
When you learn of a suspension or cancellation, make a contract with a new OSGB via ISG-KATİP without delay and take over your documents with a signed record. For the transition steps, see our article on the OSGB change process. It is also useful to add a clause to your contract stating that the OSGB will notify you in writing on the day it receives a suspension or cancellation notice.
Bursa Sistemer OSGB’s authorisation details
Bursa Sistemer OSGB is a Ministry-authorised OSGB headquartered in Nilüfer, Bursa, and provides services in Bursa and Yalova, Kocaeli, Sakarya, Bilecik, Kütahya and Balıkesir. We recommend applying the steps in this article to us as well: you can ask for a copy of our authorisation certificate at the quotation stage and check it against the list on ISG-KATİP. For the scope of our occupational safety specialist service, see the relevant page, and for other questions to ask when choosing an OSGB, see our article on what to look for when choosing an OSGB. Our article on the legal liability of the OHS specialist complements this one on the reporting obligations of the specialist and the OSGB.
Frequently Asked Questions
Where can I find out whether an OSGB is authorised?
You can download the List of Authorised OSGBs and TSMBs on the ISG-KATİP home page without logging in and search for the OSGB by its trade name. Compare the information in the list with the copy of the authorisation certificate you requested from the OSGB.
How long is the OSGB renewal period?
The authorisation certificate is renewed every five years. The period is calculated from the date the certificate was first issued; the OSGB applies no more than 60 days before the five years expire. The certificate of an OSGB that does not apply on time is suspended until the renewal is completed.
What happens to my contract if the OSGB’s authorisation is suspended?
A suspended OSGB cannot exercise its powers; in a suspension caused by renewal, existing contracts are cancelled according to the Ministry’s guide. Your workplace is effectively left without a specialist or physician, and you need to make a contract with a new OSGB quickly.
Can an OSGB in another province serve my workplace in Bursa?
An OSGB can provide services in the province where it is established and in the provinces bordering it. Bursa’s neighbouring provinces are Yalova, Kocaeli, Sakarya, Bilecik, Kütahya and Balıkesir; an OSGB in any other province cannot provide services unless it opens a branch in Bursa.
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Bursa SİSTEMER OSGB Technical Team — written from the field experience of our OHS specialists and workplace physicians. Legal information is valid as of the publication/update date; contact us for an assessment specific to your business.