An oil company association has accused classification societies of undermining the International Maritime Organisation's (IMO) ship-quality assurance scheme by backing a rival programme.
The practice was confusing the industry and could harm ship safety, OCIMF spokesman Gerhard Kurz said.
Mr Kurz said the OCIMF was holding talks with the International Association of Classification Societies to bridge the gap between the IMO's enhanced survey programme (ESP) and the ship condition assessment programme (CAP).
'We should not have two systems floating around which might only hurt ship safety,' he said.
All oil tankers and single skin bulk carriers have to undergo a special ESP every five years. The programme has stringent safety checks.
Mr Kurz said CAPs, which rate tankers in terms of structure and maintenance, varied in standard.