CLIA Provider-Performed Microscopy (PPM) Certificate Explained
A CLIA Certificate for Provider-Performed Microscopy (PPM) covers listed microscopy exams, such as wet mounts, KOH preps and urine sediments, plus waived tests. They must be done by a physician, qualified midlevel practitioner or dentist during the patient visit using bright-field or phase-contrast microscopy (42 CFR 493.19). Accuracy must be verified twice a year.
Last reviewed Oct 2026 · By Sound Lab Consultants CLIA team · Sources: 42 CFR 493.19, 493.1355-493.1365, 493.1236(c); CMS PPM brochure. General information, not legal advice; confirm against the current eCFR and CMS guidance.
Proposed change (not in effect): the October 8, 2026 CLIA proposed rule (CMS-3478-P) would change parts of this topic. See our CLIA proposed rule 2026 summary. Current rules apply until a final rule is published.
Key facts and official sources
PPM procedures. Source: 42 CFR 493.19
PPM personnel. Source: 42 CFR 493.1355-493.1365
Accuracy verification twice a year. Source: 42 CFR 493.1236(c)
Many physician, midwife and dermatology practices perform simple microscopic exams during patient visits. Those exams aren't waived, but CLIA has a dedicated certificate for them: the Certificate for Provider-Performed Microscopy Procedures (PPM). This page explains what it covers and what PPM labs must do.
Not sure where your lab stands? Sound Lab Consultants helps labs with lab director and technical consultant services, inspection readiness and deficiency response.
What are PPM procedures (§493.19)?
PPM procedures are a subcategory of moderate complexity testing. To qualify, the exam must be performed by a qualified provider, with the microscope as the primary instrument, limited to bright-field or phase-contrast microscopy (§493.19(b)(3)), on a specimen that is labile or where delay could compromise the result, with limited specimen handling. §493.19(c) limits PPM to these nine procedures (plus waived tests):
All direct wet mount preparations for the presence or absence of bacteria, fungi, parasites and human cellular elements
Potassium hydroxide (KOH) preparations
Pinworm examinations
Fern tests
Post-coital direct, qualitative examinations of vaginal or cervical mucus
Urine sediment examinations
Nasal smears for granulocytes
Fecal leukocyte examinations
Qualitative semen analysis, limited to the presence or absence of sperm and detection of motility
HHS can revise the list through a Federal Register notice with public comment (§493.19(d)), so check the current §493.19.
Who may perform PPM procedures?
PPM must be performed by a physician, midlevel practitioner (such as a nurse practitioner, physician assistant or certified nurse-midwife) under a physician's supervision or in independent practice only if authorized by the State, or a dentist, during the patient's visit, on a specimen from their own patient or a patient of their practice (§493.19(b)(1), §493.1363). Medical assistants and nurses who aren't midlevel practitioners can't perform PPM procedures, even with training.
What does a PPM certificate allow?
A PPM certificate covers PPM procedures plus waived tests. If you add any other moderate or high complexity test, you need a Certificate of Compliance or Accreditation instead. See CLIA certificate types.
What are the requirements for PPM labs?
PPM labs aren't routinely surveyed, but they must meet the applicable CLIA requirements, including:
Personnel (§493.1353 through §493.1365): a qualified laboratory director (§493.1357) who oversees the testing, and qualified testing personnel (§493.1363)
Procedure manual and quality control appropriate to each procedure, for example checking stains and reagents
Competency of each person performing PPM, assessed and documented
Verification of accuracy at least twice a year (§493.1236(c)). PPM procedures don't have regulated analytes for PT, so the lab must verify accuracy another way, for example by splitting samples with another qualified provider or by using an external survey.
Record retention under §493.1105. See our retention guide.
Fees and renewal every two years
How do you apply for a PPM certificate?
Submit Form CMS-116 to your State Agency, selecting the PPM certificate and listing your PPM and waived tests. See our CMS-116 guide. If you already have a Certificate of Waiver, use CMS-116 to change certificate type, and don't perform PPM procedures until the new certificate is issued.
How should PPM labs document quality?
Keep a simple log for each procedure: date, patient identifier, provider, result, and any reagent or stain checks performed. File the twice-yearly accuracy checks with the provider's name and the outcome, and keep training and competency records for every provider who performs PPM. These records are what an inspector asks for first if the lab is ever surveyed.
What are common PPM problems?
Exams performed by staff who aren't qualified providers
No twice-yearly accuracy verification
No written procedures or competency records
Tests added beyond PPM, such as an automated urinalysis analyzer that isn't waived, without upgrading the certificate
When should a lab move beyond PPM?
Practices that want in-house moderate complexity testing often start with waived and PPM, then upgrade. See upgrading from waived to moderate or high complexity.
Frequently asked questions
Can a nurse or medical assistant perform PPM?
No. PPM must be performed by a physician, midlevel practitioner or dentist (§493.19, §493.1363).
Does a PPM lab need proficiency testing?
PPM procedures aren't regulated analytes, but the lab must verify accuracy at least twice a year (§493.1236(c)).
Can a PPM certificate lab do waived tests?
Yes. A PPM certificate covers PPM procedures and waived tests.
Are PPM labs inspected?
They aren't routinely surveyed, but CMS or the State Agency can inspect them, for example after a complaint.
Talk to a CLIA consultant
Sound Lab Consultants provides lab director and technical consultant services, inspection readiness and mock surveys, deficiency and sanctions response, new lab startup, and waived-to-moderate/high complexity upgrades.
Regulation sources: 42 CFR 493.19, 493.1355-493.1365, 493.1236(c); CMS PPM brochure