These companies joined the ship-to-ship transfer monitoring system during February and March of this year.
This brings the number of subscribers up to 25, the company said.
The onlineSTS.net service (SCREENING and OSIS) provides tanker operators with the ability to maintain high STS safety policy standards, according to statutory and industry requirements, with reference to the encountered risks and duties for all STS stakeholders, without adding further work load to the shore personnel, the company claimed.