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Type 1 · Individual ✓ Active NPI ✓ Valid NPI checksum Sole proprietor

Mr. Mark D Harrison, ACA,NBC-HIS

Hearing Instrument Specialist in Easton, MD · enumerated 2007 · practices at International Hearing System, Inc..

Data current as of Jul 13, 2026 · sourced from CMS NPPES

National Provider Identifier

1730384710

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Registry record

Entity type Individual (Type 1)
Name Mr. Mark D Harrison
Credential ACA,NBC-HIS
Sex Male
Practice address Easton, MD, 21601
Phone (410) 822-1070
Fax (410) 822-7780
Enumeration date Jun 19, 2007
Last updated in NPPES Jul 10, 2007

Street address withheld: NPPES sole-proprietor addresses can be home addresses. See our data policy.

Taxonomy & licenses

237700000X Hearing Instrument Specialist Speech, Language and Hearing Service Providers · License 654316 (MD) Primary

Other identifiers

Identifier Type State Issuer
607209-01 Other MD MEMBER NO.

What is an NPI number?

A National Provider Identifier (NPI) is a unique 10-digit number that CMS assigns to every U.S. healthcare provider and organization under HIPAA. Type 1 NPIs identify individual providers; Type 2 NPIs identify organizations. The NPI appears on insurance claims, prescriptions, and credentialing paperwork, and never changes, even if the provider moves or changes specialty.

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Frequently asked questions

What specialty is Mark Harrison?
Mark Harrison is registered in NPPES with the primary taxonomy of Hearing Instrument Specialist. The taxonomy code describes the provider's classification and area of specialization for claims and credentialing.
Is this the official NPI registry?
No. NPI Portal is a private site built on public CMS NPPES data. The official registry is npiregistry.cms.hhs.gov, operated by CMS.

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Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2007-07-10.