The severity rating scales support consistency in determining service delivery times for students who are Blind or Visually Impaired. Use the scales to establish how often a particular service should be delivered to a student.

Please note: We are currently updating our VSSRS documents and expect them to be ready to access in spring 2024. In the meantime, please use the document below to assist in making recommendations for your students. We will share an update via the MDE-LIO email list when the new documents are ready to use.

Vision Services Severity Rating Scales (VSSRS)


For visual impairment services delivered by teachers and teacher consultants.

Download VSSRS [PDF]

Orientation & Mobility Severity Rating Scales (O&MSRS)


For orientation and mobility services.


For orientation and mobility services delivered to students with additional needs.