Now is a good time to take a hard look at your current liquid nitrogen contract. If your contract is expiring in the next 1-3 years, you should send a letter to your supplier now informing them you would like to terminate the contract once it expires. This will give you flexibility when it comes time to either renegotiate a new contract or look at options such as nitrogen generation. If you do not give notice, the contact automatically renews for another year.