If you need to exchange sensitive information with external (or internal) customers, you should only use approved, secure mechanisms.
While email is a convenient form of communication -- it is not considered secure -- especially when exchanging sensitive information such as social security numbers, driver license numbers, passport numbers, or financial information.
Secure File Exchange
If you need to send (or receive) file attachments that contain sensitive information, Whitman College maintains a service that allows you to accomplish this – it is called ShareFile.
This mechanism allows you to expire download links and get notifications when someone downloads or uploads a file attachment.
Use cases: sending tax forms to a previous employee, requesting a form, application, or PDF scan that may contain SSN, etc.
Instructions can be found here: File Exchange
Secure Text Exchange
If you need to send short messages that contain sensitive information, Whitman College recommends the third party service called One Time Secret.
This mechanism only allows the "secret text" to be viewed once - it self-destructs after access.
Use cases: sending someone the initial password for activating an account, etc.