LR issues the first Direct Damage Stability certificate to Onboard-NAPA

The IACS Unified Regulation L5 (IACS UR L5) clearly stipulates that stability software installed onboard shall cover all stability requirements applicable to the ship, thus including also damage stability. The requirements of this Unified Regulation apply to stability software on ships contracted for construction on or after 1 July 2005.

According to Lloyd?s Register procedures, a General Certificate is needed prior to the issuance of any ship-specific approval of loading computer software. The work targeting to the General Certificate was started following the detailed instructions published by LR.

During the exhaustive process using several purpose specific test vessels, the existing Onboard-NAPA direct damage stability module was developed and improved to meet LR requirements and interpretations of the Codes. The work was carried out in close co-operation with the leading experts from LR stat-comp department, including also simultaneous development of the LR procedure and requirements.

The outcome is an efficient, easy-to-use software module enabling the ship officers to check the damage stability compliance of their planned loading condition by one push of a button.

All tanker type vessels involved in international trade must comply with the IMO requirements for damage stability when loaded with cargo. These requirements are defined in MARPOL, IBC and ICG codes.

The only relevant method for verification of the compliance of an actual operational loading condition is the direct damage stability method. This means that all deterministic two-compartment damages (as defined in the Codes) are calculated for the actual loading condition and the results are verified against all the criteria laid down in the Codes.

Since no pre-calculated results or tables can be utilized, the only way to cope with this task is to use a modern loading computer system based on a 3-D ship model together with a powerful calculation engine. Onboard-NAPA Loading Computer software has been a forerunner in this field by offering direct damage stability calculation since 1993. The Onboard-NAPA direct damage stability module has previously been approved by other leading classification societies before the adoption of IACS UR L5.