We study intersection matrix algebras im(A^d) that arise from affinizing a Cartan matrix A of type B_r with d arbitrary long roots in the root system $Delta_{B_r}$, where $r geq 3$. We show that im(A^d) is isomorphic to the universal covering algebra
of $so_{2r+1}(a,eta,C,chi)$, where $a$ is an associative algebra with involution $eta$, and $C$ is an $a$-module with hermitian form $chi$. We provide a description of all four of the components $a$, $eta$, $C$, and $chi$.
