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A facility that performs testing on materials derived from the human body for the purpose of providing information for the diagnosis, prevention, or treatment of any disease or impairment of, or assessment of the health of, human beings.  This also includes procedures to determine, measure, or otherwise describe the presence or absence of various substances or organisms in the body. 

Shared Laboratory

A shared laboratory is one where two or more sole practicing physicians bill Medicare and/or Medicaid individually but collectively pool resources to fund a laboratory’s operations.  The definition of a shared laboratory may also include two or more physician group practices that share the expenses for the laboratory’s operation.
NOTE:  This definition of a shared laboratory is for the purpose of registering laboratories in the CLIA program; it may not meet the definition of a shared laboratory according to the Medicare regulations regarding proper billing procedures in shared laboratory arrangements.

Multiple Site Certificate

A multiple site certificate is one a facility may obtain if they meet one of the following exceptions:

  1. Laboratories that are not at a fixed location; that is, laboratories that move from testing site to testing site, such as mobile units providing laboratory testing, health screening fairs or other temporary testing locations may be covered under the certificate of the designated primary site or home base, using its address.
  2. Not-for-profit or Federal, State, or local government laboratories that engage in limited (not more than a combination of 15 moderately complex or waived tests per certificate) public health testing may file a single application.

NOTE:  Laboratories applying for this exception MUST provide a copy of their Federal Not-for-profit 501(c)(3) Tax Determination Letter from the US Department of the Treasury, Internal Revenue Service.

  1. Laboratories within a hospital that are located at contiguous buildings on the same campus and under common direction may file a single application or multiple applications for the laboratory sites within the same physical location or street address.  (This exception is only for hospitals.)

Mobile Unit

A movable, self-contained operational laboratory with its own personnel, equipment and records.  In order to be considered a mobile unit, equipment must be installed and located permanently within the mobile unit.  If a vehicle is used to transport laboratory equipment from the primary site/home base to another site where testing is performed, the transporting vehicle is not a mobile unit.
NOTE:  If you are applying for a CLIA certificate as a mobile unit, you must include the Vehicle Identification (VIN) number of the mobile unit in which testing is performed. 

Temporary Testing Site:

A temporary testing site is where, at various intervals of time, an entity that is not at a fixed or permanent location performs laboratory testing. The laboratory moves from testing site to testing site. The laboratory’s CLIA certificate is in the name of the home base or designated primary site. Examples of a temporary testing site would be a Home Health Agency patient’s home, or a health screening event held by a community clinic at a local church.
NOTE:  Home Health Agencies performing testing in patients’ homes MUST request the Multiple Site Exception that covers temporary testing sites, and MUST include a copy of their Illinois Department of Public Health Home Health Agency License with their CLIA application for processing. 

Primary Site or Home Base:

The location where the staff is based and records, equipment, supplies, etc. are maintained.  For example, the main office for an ambulance service.