Any user that has edit or admin role in the project which the application is running in, can create a terminal session for pods running in that project.

oc adm policy add-role-to-user edit <collaborator>

The purpose of the different roles you can grant are:

• admin - A project manager. The user will have rights to view any resource in the project and modify any resource in the project except for quota. A user with this role for a project will be able to delete the project.
• edit - A user that can modify most objects in a project, but does not have the power to view or modify roles or bindings. A user with this role can create and delete applications in the project.
• view - A user who cannot make any modifications, but can see most objects in a project.

A user with view role cannot create a terminal session as that would mean they could modify things.