A block is a restriction that prevents a Rail Industry Worker from working on a specific rail network or on multiple rail networks. The block can be placed at two levels in the system:

1. National Level: which impacts all work sites on all participating rail networks (a national block is referred to as a Rail Industry Worker Program Block).

2. Network Level: which includes all work sites on a specific network only.

These blocks are visible by Access Controllers and Spot Checkers when a worker’s card is swiped.