ClassNK has informed the requirements related to computer based systems by ClassNK Technical Information TEC-1114 issued on 16 June 2017 (revoked) and TEC-1145 issued on 28 February 2018. In view of the recent situation, ClassNK reviewed the contents of the Technical Information TEC-1145 and has issued TEC-1235 alternatively.
ClassNK Technical Information TEC-1145 is revoked by this Technical Information.

IACS UR E22 (Rev.1) specified requirements related to configuration and function of computer based systems used for systems such as control, alarm, and safety systems. These requirements have already been incorporated in Rules and Guidance of NIPPON KAIJI KYOKAI (hereinafter referred as "the Society"). Furthermore, IACS has focused on the importance of quality control of computer based system software and has reviewed the unified requirement. As a result, IACS adopted UR E22 (Rev.2) in June 2016 in order to clarify the roles of stakeholders regarding computer based systems used on vessels and the requirements for quality control of the life cycles of software (hereinafter referred to as "SW") and hardware (hereinafter referred to as "HW") to be used in computer based systems.
Accordingly, relevant requirements in the Society's Rules and Guidance were amended and have been applied to vessels, machinery/systems. However, in view of the application of these rules so far, and in correspondence to diversifying computer based systems and inquiries from manufacturers and shipyards, ClassNK Technical Information TEC-1145 is amended.

[Summary of Rules]
The Rules apply to SW and HW for computer based systems used on vessels, as stipulated in Annex D18.1.1, Part D of Guidance for the Survey and Construction for Steel Ships. The computer based systems are assigned to three system categories according to the degree of these failure impact. The Rules apply to the SW and HW for computer based systems according to the system categories.
Furthermore, responsibilities and roles of the owner, system integrator, and suppliers to comply with the Rules are specified. In particular, the system integrator is a newly defined in stakeholder and shall take a responsibility only when an integrated system is installed. The "integrated system" means a system in which several machineries and/or systems are connected and mutually controlled, or there is a upstream system that integrates several systems, such as IAS (Integrated Automation System) that controls cargo control and monitoring system, gas fuel supply control system, and gas reliquefaction system on a liquefied gas carrier.

(To be continued)