Dim ond mewn amgylchiadau eithriadol y mae Pont Britannia yn cau i gerbydau ag ochrau uchel, ac mae hynny wedi digwydd saith gwaith y flwyddyn ar gyfartaledd yn ystod y pum mlynedd ddiwethaf.
The closure of the Britannia Bridge to high-sided vehicles only happens in exceptional circumstances. In the last five years, the bridge has been closed to high-sided vehicles on average seven times a year.