March 2019


The impact of fats, oils and grease (FOG) on commercial kitchens and the wider sewer network is of growing concern to businesses, consumers and society as a whole. To help you understand more about FOG and the grease management solutions available, we’ve prepared this short Q&A.

What is FOG?

FOG is the abbreviation for the fats, oils and grease which are found in the wastewater produced by kitchens. FOG comprises fats, oil, grease created by food debris, fats and oils used in the cooking process, and the washing of food equipment, utensils and crockery. All kitchens produce wastewater which contains fats, oils and greases (FOG) as well as food debris.

Why do I need to worry about FOG?

FOG causes blockages in kitchen drainage systems, compromises hygiene, creates unpleasant odours, makes cleaning difficult and costly, can impact upon employee health and safety, and ultimately can stop your commercial kitchen from operating.

FOG is also becoming a major issue for Britain’s sewer network, creating ‘fatbergs’ and causing blockages. FOG, combined with the significant use of wet wipes and other non-biodegradable items, is the major cause of sewer blockages. Industry body Water UK says there are 300,000 FOG-related sewer blockages every year in the UK, costing the country around £100-million. Thames Water alone estimates it spends £18-million per year clearing the 75,000 blockages experienced across its network.

What does this have to do with commercial kitchen operators?

Every foodservice outlet in the country has a legal obligation to “manage effluent content” under the Water Industry Act (1991). Section 111 of The Water Industry Act (1991) gives water companies the power to bring a criminal proceeding against anyone who causes injury or inhibits the free flow of the sewer network. As FOG is a major cause of sewer blockages, under this Act the water companies have the power to prosecute for FOG contamination and also to recharge any costs incurred to clear blockages. Aside from the legal obligation to help tackle FOG, responsible commercial kitchen operators are keen to use grease management systems to minimise the impact of their FOG for the benefit of our living and working environments.

What is Grease Management?

Grease management refers to the use of a range of products and systems which effectively remove FOG from waste water and so prevent the issues which FOG can cause in a kitchen’s drainage system and the wider sewer network.

What grease management solutions are available to prevent FOG from entering my drainage and the wider sewer network?

A wide range of solutions are available including grease separators, grease traps and grease recovery units also known as GRUs. It is important to specify the right grease management solution for your business and, to ensure it continues to operate effectively, to conduct ongoing maintenance.

Why are there so many different products and solutions to choose from?

Different types and size of commercial kitchen require different grease management solutions. Your choice of grease management solution will depend on a variety of key specification criteria including the size of your kitchen, the type of food you prepare, the equipment used for food preparation, the contents of your waste water, the density of the FOG produced and the space you have available for the installation of a grease management solution.

How can I ensure that I specify the most appropriate grease management solution for my business?

There are numerous sources of impartial information which will provide you with guidance. ACO has also developed a Product Selector for commercial kitchen operators which can be found on our website For project-specific guidance, you can also talk with our in-house technical team who help you choose the right grease management solution for your business.

What are the cost implications of fitting a grease trap?

The initial capital cost of the grease management system that you choose will vary enormously depending on what you purchase. It is important to recognise that there will be regular maintenance and service requirements to ensure that the system remains problem free and provides the performance that you expect. It is worth reviewing this aspect before a purchase is made to understand the ongoing costs and requirements.

Will local authorities/ water companies provide grants to fit one?

It is unlikely that you will get any financial assistance from either your local authority or the local water company responsible for your sewer. We would suggest that you ask your local water company, local Environmental Health Officer or British Water ( for guidance.

Why choose ACO?

ACO Building Drainage is the established leader in the provision of hygienic floor drainage systems and provides grease management systems designed and manufactured to support the functionality of commercial kitchens both large and small. We have more than 60 years’ experience of designing and manufacturing high performance drainage solutions, and our in-house design team provides tailored solutions to suit individual client requirements. To give you optimum peace of mind and a complete grease management solution, we can also put you in touch with our service and installation partner, who can manage your commissioning, installation and maintenance requirements.

If you would like more information about our range of grease management solutions or would like specification advice for your commercial kitchen, visit the grease management section on this website or contact our in-house technical design team on 01462 810421.