Regulatory requirements for offshore chemicals in the North Sea

Materials World magazine
1 Jun 2016

Dr Rosalinda Gioia discusses the regulatory requirements placed on chemicals used in offshore extraction in the North Sea.

The recovery of oil and gas from offshore subsea reservoirs requires a wide range of chemicals to enhance drilling performance, promote chemical production and the separation of oil or gas, to protect equipment from corrosion and maintain safety. Since the start of oil and gas chemical production in the North Sea in the mid 1960s, the regulation of chemicals used by the offshore industry has evolved from a basic screening of chemical hazard into a more comprehensive assessment and management of the risks.

The use of offshore chemicals can result in operational discharge during drilling, well cleaning and preparation, and separation of oil/gas and condensate from water naturally present in reservoirs. As such, a robust regulatory framework that ensures an adequate level of protection is critical. That was the main objective the Convention for the Protection of the Marine Environment of the North-East Atlantic, otherwise known as the OSPAR convention, and the Harmonised Mandatory Control Systems (HMCS) produced aim to protect the marine environment by promoting the use of less hazardous, or preferably non-hazardous substances. 

A study into the substitution of hazardous offshore chemicals in 2015 by La Vedrine et al stated that more than 91% of discharge in the UK Continental Shelf comes from corrosion inhibitor, scale inhibitor, demulsifier and water clarifier formulations. The discharge of corrosion inhibitors accounted for the largest contribution to substitutable substance discharges. 

The review also highlighted how the discharge of chemicals with different functions decreased from 2000 to 2012. For example, discharge of substitutable substances (SSs) in scale inhibitors has decreased steadily, while SS discharges attributable to corrosion inhibitors have remained fairly constant since 2007, and appear to be the type of product with the fewest options for substitution.

The regulatory structure

In the UK and the Netherlands, the requirements of HMCS are incorporated in the Offshore Chemical Notification Scheme (OCNS). The scheme is administered and enforced by the Department of Energy and Climate Change (DECC) in the UK and by the State Supervision of Mines (SSM) in the Netherlands. The offshore industry regulators are responsible for ensuring all chemicals used by the oil and gas exploration and production industry on the UK and the Dutch continental shelf are registered under the OCNS and their environmental hazards evaluated before their use and discharge is permitted. This assessment is conducted by the Centre for Environment, Fisheries and Aquaculture Science (Cefas) in the UK on behalf of DECC and SSM.

The OCNS identifies chemical hazards and potential impacts to the marine environment when offshore chemicals are used and discharged in UK and Dutch waters. The hazard pre-screening and ranking of chemicals is based on ecotoxicological information on Persistence, Bioaccumulation and Toxicity (PBT) characteristics of the chemical constituents of offshore products. The chemical supply industry provides this information to Cefas, via the Harmonised Offshore Control Notification Form (HOCNF), so that their products can be registered for use offshore. The ecotoxicological data is generated through the use of a number of internationally accepted standard protocols (e.g. OECD) and chemical suppliers will normally commission these tests to be conducted by a specialist testing laboratory. 

In addition to using standard methods, it is required that studies are conducted according to Good Laboratory Practice (GLP), an internationally recognised quality system of management controls on how studies are planned, monitored, recorded, reported and archived. 

Some substances are exempt from the requirement for test data – natural materials, salts and similarly benign substances considered to pose little or no risk, and substances for which sufficient information is known that they are considered to cause minimum risk because of their intrinsic properties, (REACH Annex IV (EC) No 987/2008) or satisfy the criteria detailed in REACH Annex V. 

The introduction of REACH

On 1 June 2007 the Regulation (EC) No 1907/2006 of the European Parliament and of the Council of 18 December 2006 concerning the Registration, Evaluation, Authorisation and Restriction of Chemicals (REACH) entered into force. Central to the REACH Regulation is the concept of ‘no data, no market’. 

Companies introducing chemicals onto the EU market have to demonstrate their safe use, or that it is possible to control their risks. This is done via submission of a registration dossier that contains information on the hazards as well as a risk assessment for identified uses of the substance. The onus is on industry, rather than the regulators, to demonstrate the safe use of chemicals. Since the introduction of REACH, there have been several discussions of its impact on the OSPAR framework for offshore chemicals. The OSPAR Contracting Parties are also EU Member States and therefore obliged to follow REACH as well as OSPAR, leaving the chemical industry to face the challenges and the demands of overlaps and conflicts of the two regulatory schemes. 

One of the main differences is that REACH regulates the use of chemicals in order to achieve an appropriate level of protection and contains no provisions for the discharges of chemicals in the offshore environment. The REACH implementation timeline spans 10–15 years from when the regulation came into force to the last submission deadline of 2018. The registration deadlines have been set out to register the most hazardous and highest volume substances first. 

By 2018, all chemical substances used offshore will need to have been registered under REACH. The OSPAR Offshore Industry Committee (OIC), which implements the oil and gas sector-related work, agreed to re-establish its intersessional correspondence group on REACH, to facilitate the HMCS/REACH harmonisation process and analyse its implications. The two systems work differently in terms of exemptions, substitution strategies and the assessment of risks and hazards. It will be challenging to eliminate some of the differences between the two regimes, proving harmonisation difficult to achieve. There will probably be aspects where OSPAR will need to harmonise with the REACH requirements, but it is already clear that data currently required by REACH should not be duplicated within the HMCS framework.

The regulatory requirements are set out in the OSPAR Recommendation 2000/2 on a Harmonised Mandatory Control System (amended by OSPAR Decision 2005/1).To read more, visit

Dr Rosalinda Gioia is Managing Regulatory Scientist at The REACH Centre Ltd. An internationally recognized expert on ecotoxicology, Gioia understands the challenges that the chemical industry is facing to meet regulatory compliance and provides expert scientific advice and policy support on hazard and risk assessments for offshore chemicals. She has provided expert scientific advice and policy support to government regulators on chemical risk assessments relating to the oil and gas industry, for which she has authored technical bulletins and papers to the annual meeting of OSPAR's Offshore Industry Committee.