 A path in a fan \(\sigma\) is a sequence \(\alpha\), finite or infinite, such that \(\bar{\alpha}(n) \in \sigma\) for each applicable \(n\). We say that a path \(\alpha\) is blocked by a subset \(B\) if some restriction of \(\alpha\) is in \(B\); if no restriction of \(\alpha\) is in \(B\), we say that \(\alpha\) misses \(B\). A subset \(B\) of a fan \(\sigma\) is called a bar for \(\sigma\) if each infinite path of \(\sigma\) is blocked by \(B\); a bar \(B\) for \(\sigma\) is uniform if there exists \(n \in \bN\) such that each path of length \(n\) is blocked by \(B\).