Further details of these concessions are available at GOV.UK: Toll Concessions.
In some cases you will have to apply in advance to qualify for a concession. As toll operators sometimes vary their concessions it is a good idea to check with the owners or operators before you travel.
Tyne Tunnel Disability Exemption Accounts
Disability Exemption Accounts are available for the Tyne Tunnel.
To apply, go to Toll Exemption Accounts.