No. There is no overall minimum or maximum time for Transnational Access. Limitation is that Community financial support should never exceed 20% of the annual operating costs of the infrastructure to prevent it from becoming dependent on the Community contribution. Another aspect is that in the Work Package description for Transnational Access you have to provide an implementation plan which also shows the minimum quantity of access to be provided (see Guide for Applicants). TA is the main purpose of a project and must be explicitly integrated in a project.

One has to differentiate between TA-time for the whole project on one hand and TA-time for access of one user group on the other hand:

- Whole project: the access should be provided during an essential part of the project in order to gain significant impact on the target research community.

One could advise for a project of four years that access should be provided during ca. three years;

- Single access: here there is no formal minimum access time. This is due to the fact that the needs of the RIs differ widely. So in one RI access can be done in 2 days including all preparations, whereas the experiments in another RI may take e.g. 10 days.