Patent ID: 6966724

Claim:
A negative pressure storage tank including a manhole, comprising: a) the manhole having an openable and closable outwardly opening manhole cover; b) a manway defining the manhole, the manway being provided on the negative pressure storage tank; c) the outwardly opening manhole cover being hingedly attached to the manway; d) the outwardly opening manhole cover including a hinge frame assembly; e) a seal provided on the negative pressure storage tank manway; f) a pin provided for securing the outwardly opening manhole cover to the manway; g) a locking and sealing assembly being provided adjacent to the outwardly opening manhole cover; and h) the locking assembly including a locking and sealing element for engaging the outwardly opening manhole cover with the seal for locking and sealing the negative pressure storage tank manway on the negative pressure storage tank.