Shipowners would also be in breach of the clause if at the time of delivery of the vessel to the charterers she did not have a deratisation certificate since without the certificate she could not trade as the charterparty provided or for the contemplated purpose. The words “in every way fitted for cargo service” do not impose an absolute obligation on the shipowners to deliver the vessel in a fit condition but only to use reasonable diligence to do so. The test for seaworthiness is would a prudent owner have required the defect to be remedied before sending his ship to sea if he had known of it?  If he would the ship is unseaworthy. Unseaworthiness includes lack of sufficient bunker fuel for the voyage or, where the voyage is a long one, for the particular stage of the journey during which the loss occurs. The undertaking as to seaworthiness is that the vessel is fit to receive the particular cargo at the time of loading so that a defect arising after the cargo has been shipped is no breach of this undertaking and the vessel is seaworthy at the time of sailing. A clause in a charter party that the vessel is to be “tight staunch and strong, and in every way fitted for the voyage” relates to the preliminary voyage to the port of loading. It refers to the time at which the contract is made or to the time of sailing for the port of loading. The undertaking for seaworthiness implied by law relates to the time of sailing from the port of loading. A breach of the implied undertaking of seaworthiness at the port of loading entitles a charterer to refuse to load but the breach would have to be such as to frustrate the object of the charter. The difference arises because the charterer’s obligation to load is conditional on the ship being seaworthy at the port of loading not upon her being seaworthy at the time the contract was made. The seaworthiness obligation can be limited at common law (unlike under the Hague-Visby Rules), but it must be expressly excluded, and in the clearest words: the courts adopt a presumption that an exemption clause does not apply to unseaworthiness unless expressly so stating. Any ambiguity will be construed against the shipowner. The seaworthiness obligation applies equally to time as to voyage charter parties. The second term implied under Common Law is that the ship shall proceed with reasonable despatchThe ship must be ready to commence the voyage agreed on and to load the cargo to be carried and shall proceed upon and complete the voyage agreed upon with all reasonable despatch. A breach of this implied undertaking gives the charterer the right to repudiate the contract if the delay is so serious as to go to the root of the contract. Otherwise, the only remedy is damages. Thirdly, Common Law requires that there should be no unjustifiable deviation. At Common Law, deviation will only be justifiable where it is to save life. At Common Law deviation to save property is unjustifiable unless expressly stipulated in the charter party (this can be contrasted with the position under the Hague-Visby Rules, whereby deviation to save property is considered as justifiable). Deviation is also justified at Common Law for purposes necessary for the prosecution of the voyage or for the safety of the venture. A master is required to use all reasonable care to bring the venture to a successful conclusion protecting the ship and cargo from undue risks. If a ship sustains such damage that repairs are necessary the master must put in to the nearest port at which such repairs can be effected. The same doctrine applies in the case of any other grave peril threatening the ship or her cargo. A deviation would be justified even if necessitated by the ships unseaworthiness at the commencement of the voyage if it would be dangerous to keep her at sea without effecting such repairs.