Accreditation to ISO 15189 is often discussed as a project with a finish line. For the people at the bench and the sign-out desk, it is better understood as a set of daily habits. This article is for pathologists, histotechnologists and lab managers who want to know what ISO 15189 actually changes in routine anatomic pathology work.
ISO 15189 in brief
ISO 15189 is the international standard for medical laboratory quality and competence. It combines requirements for how the lab is organized and managed with requirements for the technical work itself: personnel, facilities, equipment, methods and the whole examination process from request to report. Accreditation is granted by an accreditation body that assesses the lab against the standard and returns for regular surveillance.
The standard has been revised over the years, and the current edition places clear emphasis on risk management and on the patient as the reason the laboratory exists. In practice, that means assessors expect you to show how you identified what could go wrong and what you did about it, not just that you have procedures.
ISO 15189 does not tell you how to cut a block or which antibody clone to use. It tells you to define, validate, control and record what you do, and to show that your staff are competent to do it. If your lab already runs a working quality management system, much of this will feel familiar. The difference is consistency and evidence.
At accessioning
Accessioning is where many errors start, so it is where assessors often look first. Day to day, the changes look like this:
- Specimen acceptance and rejection criteria are written down and applied the same way by everyone, on every shift.
- Unlabeled, mislabeled or mismatched specimens follow a defined path that is recorded, rather than being resolved informally by phone.
- Receipt time, condition and any deviations are captured at the point of receipt.
- Where professional guidelines set expectations for ischemic and fixation times, as they do for some biomarker tests, those times are recorded with the case.
- Every deviation is logged as a nonconformance, even when it is fixed within minutes.
The extra seconds per specimen are the price of traceability. They also make later investigations far faster.
At the grossing bench
Grossing is interpretive work with permanent consequences, because tissue that is not sampled cannot be examined later. Under ISO 15189, a few things become routine:
- Only authorized, competency-assessed staff gross, and the scope of each person's authorization is documented, for example which specimen types a trained technologist or pathologists' assistant may handle.
- Grossing follows written protocols for common specimen types, covering orientation, measurements, inking and sampling.
- The cassette count and block key in the gross description match what actually goes to processing.
- Equipment such as balances, fume extraction and refrigerators have maintenance and check records.
None of this slows an experienced prosector much. What it removes is variation between people and the silent gaps that appear when a new staff member learns by watching.
In the histology lab
Histology is where ISO 15189 most visibly adds records. Expect to see:
- Reagent control: lot numbers, opening dates and expiry tracked for stains, antibodies and consumables.
- Run QC: control tissue included with special stains and immunohistochemistry, and acceptance documented before slides are released.
- Method validation and verification: a documented study before a new antibody, protocol or instrument goes live, and again after significant changes.
- Equipment records: processor and stainer maintenance, temperature logs for water baths, ovens and fridges.
- Defect tracking: recuts, re-embeds and poor-quality slides recorded so trends can be reviewed.
The common pushback is that these records duplicate what experienced histotechnologists already know. That is true. The point is that the lab, not just the individual, knows it.
At sign-out and reporting
For pathologists, ISO 15189 mostly formalizes good practice:
- Report content is defined. Required elements for common cancer specimens are often best handled with synoptic reporting.
- Amended and corrected reports preserve the original, state the reason for the change, and are communicated to the clinician.
- Critical or unexpected findings are communicated according to a defined procedure, and the communication is recorded: who was told, when and by whom.
- Intradepartmental consultations and case reviews are documented, not just discussed in the corridor.
- Turnaround times are monitored against targets agreed with the clinical users of the service. Our guide to reducing turnaround time in surgical pathology covers what to do when they slip.
Competence, training and the people side
Personnel requirements are where many labs underestimate the work. Every role needs a job description, training records and evidence of initial and ongoing competency assessment. This applies to pathologists as well as technical staff.
For technical staff, competency is commonly assessed through direct observation, review of work, blind samples and problem-solving exercises. For pathologists, labs use approaches such as participation in external quality assessment, review of a sample of signed cases and documented continuing education. The method matters less than having a defined approach that is applied regularly and recorded.
Authorization is the other half. A person may be trained but not yet authorized to perform a task independently. The lab should be able to show, for any given day, who was authorized to do what.
The rhythm of the year
ISO 15189 introduces a predictable cycle that sits on top of daily work:
- Internal audits on a planned schedule, covering every part of the lab over a defined period.
- External quality assessment or interlaboratory comparison for the examinations you offer, with results reviewed and acted on.
- Management review, where leadership looks at indicators, audit findings, complaints, risks and resources, and decides on actions.
- Assessment and surveillance visits by the accreditation body.
Labs that spread this work across the year cope well. Labs that compress it into the weeks before an assessment tend to burn people out and find the same problems every cycle.
Common misconceptions
- More paper means more compliance. Assessors look for control and evidence, not volume. Short, accurate procedures beat long ones nobody follows.
- Quality is the quality manager's job. The quality manager coordinates; everyone owns the quality of their own work.
- Once accredited, you are done. Surveillance and reassessment mean the habits must stick.
- The standard dictates methods. It requires that your chosen methods are validated, controlled and documented.
Key takeaways
- ISO 15189 changes daily habits more than it changes techniques.
- Accessioning and histology see the most new records; sign-out mainly formalizes good practice.
- Competency and authorization records apply to everyone, including pathologists.
- Spread audits, quality assessment and review across the year instead of cramming before assessment.
- Aim for short, accurate procedures and records that are created as part of the work.
Accreditation is easier when evidence is captured as a side effect of normal work rather than recreated afterward. If you are looking at software to support that, PATHOLOGY+ records specimen tracking, report versions and audit logs as cases move through the lab, and you can book a demo to see it in context.