The COA is committed to safe, reliable and sustainable container operations and engages with leading global flexitank manufacturers and operators to implement the COA Code of Practice and strive for the highest industry standards.


A flexitank is a large bladder with valve(s) that is designed to fit inside a general-purpose freight container and operate as part of a system which includes the container, flexitank, its fittings and restraining system.

The flexitank is designed for single-use transport of compatible liquids that are classified as non-dangerous goods i.e. goods that are not classified or regulated as dangerous goods in accordance with the IMDG Code.

Flexitanks may be constructed from polyethylene, polyethylene blends and polyvinyl chloride, but other materials can also be used.

The containers used for flexitanks are ISO dry freight 20 ft general purpose freight containers (ISO code GP22). The flexitank should be a maximum of 24000kg and 24000 litres. Flexitanks can also be designed for 40ft containers and refrigerated containers.

In addition to the transport of flexitanks in accordance with the COA Code of Practice, transport is subject to the provisions of the IMO/ILO/UNECE Code of Practice for Packing of Cargo Transport Units (CTU Code) and other statutory and industry requirements that might apply.

The global use of flexitank systems has grown substantially in recent years. It is estimated that more than 900,000 flexitanks will be transported in 2019.

COA Code of Practice

The Code of Practice requires that the COA membership of flexitank manufacturers and logistics operators comply with the COA quality management system and submit to independent quality audits and tests of the flexitank.

Compliance with the Code of Practice forms part of the COA shipping line (carriers) risk assessment process when evaluating container flexitank systems for carriage by sea.

On satisfactory completion of the audits and tests, the manufacturer achieves COA Quality Compliance (CQC)

Flexitank Quality Management List (FQML)

The COA Flexitank Quality Management List (FQML) provides a list of flexitank manufacturers and operators that have been awarded the COA Quality Compliance (CQC). The CQC is not issued in document form. The FQML can be downloaded.

The list is used as a reference for shipping line risk assessment and is regularly updated.

The list is in two parts:

Table 1 – Holders of COA Quality Compliance
Table 1 lists COA member companies that achieved the COA Quality Compliance (CQC)

Table 2 – Part completion
Table 2 lists COA member companies that have completed part of the CQC process
A blank entry indicates the outstanding quality audit items

Sustainable environment

The COA supports the sustainable use of containers and flexitanks and encourages re-cycling of single-use flexitank materials.

The COA Code of Practice requires that the flexitank membership are compliant with environmental standard ISO 14001 or equivalent.

The Code of Practice requires companies to provide practical procedures to facilitate the re-cycling of used flexitanks within their installation and operation manual and to assist users of flexitanks to comply with the environmental requirements.

To facilitate re-cycling of flexitanks, the COA maintains a recycling facilities list

Upcoming Flexitank Events

Webinar 3 – Thursday 3 December 2020
Flexitanks: Presentation and Panel Discussion


Previous Flexitank Events

12th COA Flexitank Meeting – Amsterdam

12th COA Flexitank Meeting – Amsterdam

Event location - Hyatt Place Hotel, Amsterdam

Event date - 20160629

June 2015: 11th COA Flexitank Meeting

Event location - Hamburg

Event date - 20150616

Event date end - 20150616

May 2013: 9th COA Flexitank Meeting

Event location - London

Event date - 20130523

Event date end - 20130523

COA 2019 Flexitank meeting

COA 2019 Flexitank meeting

Event location - Qingdao, China

Event date - 20190524

Event date end - 20190524