How to Clean Out a Grease Trap | How Often Should a Grease Trap be Cleaned? | Top Tips and Best Practises for Efficient Grease Management
With so much publicity surrounding the discovery of a giant fatberg beneath London’s streets you’ll undoubtedly already know how important grease traps are, especially within commercial catering operations and the foodservice industry. These simple unassuming metal boxes play a massive part in preventing fats, oils and grease (aka FOG) from entering the sewer system, causing massive damage to drainage infrastructure and the environment overall. Brushing up on the basics surrounding grease traps and understanding the critical need to take grease prevention seriously will not only preserve the environment but could also protect your business from potential fines and, in some cases, imprisonment.
The journey taken by FOG can be retraced from the grotesque end result back to the source meaning that investigators can enforce legislation where necessary. Businesses are no longer able to hide behind outright denial of responsibility; if a business disregards the legislation they will be held accountable.
So, you’ve made the decision that your business needs a grease trap. You’ve calculated the size required based on contributing factors such as the number of sinks in the kitchen and the overall flow rate passing through the grease trap. You’ve decided on the specific type of grease traps for commercial kitchens, they’re all correctly installed and working as they should – that’s the hard work done, right?
Ongoing maintenance and cleaning of the grease trap is just as important as the crucial decisions made at the beginning of the process. If grease traps are neglected they will not work effectively or efficiently. Just because a kitchen has a grease trap installed it will not make them immune to fines. If the trap is deemed to be ineffective due to incorrect installation or improper cleaning for example, the business will still be liable. This further reiterates why correct cleaning and maintenance is vital.
How to Clean Out a Grease Trap
Whatever type of grease trap your business has installed, passive or automatic, they need to be cleaned albeit with differing frequencies and potentially using different methods. Cleaning can be dirty work and it’s essential to do it properly so it’s advised to use a specialist company with relevant certifications if possible. 
While larger grease traps, typically positioned externally of the building, above or below ground will require use of pumping equipment by a trained specialist to get the job done, cleaning of smaller units can be carried out in-house if preferred.
TOP TIP: Whether cleaning grease traps yourself or using a specialist company, it is a legal requirement that disposal must always be carried out by a licensed waste contractor.
PLEASE NOTE: We strongly advise hiring a professional service, in fact we advise against doing it yourself, minimising the risk of prosecution due to incorrect procedures.
A Basic Guide to DIY Grease Trap Cleaning
- Let any water cool before cleaning.
- Wear appropriate clothing and respiratory protection including overalls, gloves, goggles and mask.
- Protect the surrounding floor to limit potential contamination of the kitchen.
- Open up the tank, carefully prying off the lid being sure not to damage the gaskets or seals. Some boxes may have bolts to unscrew while others may have fasteners which need to be undone.
- Measure the quantity of FOG waste in the trap using a ruler or gauge. Take note of any
- Remove any sludge floating on top of the tank.
- Use a small bucket or scoop to remove any water from the tank.
- Scrape out solid FOG’s using a separate bucket or scoop. (It’s best to have a dedicated tool used for this purpose only)
- Remove baffles and scrape the interior surfaces of the tank as well as all components. A specialised vacuum can be used to help get rid of smaller debris. Remember to check the inlet and outlet pipes for any residual debris.
- Use room temperature water to scrub and clean the walls, base and lid of the grease trap.
- Clean baffles making sure all holes are clear and unobstructed.
- Run clean water through the trap. If water doesn’t flow as it should there may be a blockage further up in the pipe – you’ll need a plumber to sort it.
- FOG’s are packed with bacteria so it’s vital to seal any FOG securely in a leak free container ready for responsible disposal via licensed waste contractors.
- Inspect all components including lid gasket. Replace any necessary elements.
- Reinsert all components back into the grease trap and securely replace the lid.
- Complete records and mandatory forms and file away safely ready for inspection as and when required.
How Often Should a Grease Trap be Cleaned?
Whether you choose to clean your grease trap yourself or employ the services of specialist companies to do the dirty work for you, you’ll need to know how often cleaning should take place to make sure grease interceptors remain effective.
Unfortunately there are no hard and fast rules to cleaning. Regularity will be dependent on the type of grease trap installed, the level of usage and the total flow rate of water being put through the system. General advice is to monitor traps regularly, perhaps once a week to start with then tailoring the frequency of checks based on results.
Manual or passive grease traps are more labour intensive and will require regular in depth cleaning. Once the lid is removed, contamination could occur from the bacteria laden FOG so 
Automatic grease traps or grease recovery units (GRUs) are considered less hassle in relation to cleaning and can work out cheaper in the long run. Only requiring in depth cleaning every couple of months depending on usage, these models are generally the preferred choice of water companies.
TOP TIP: Never wait for FOG to be spilling from your interceptor; your system should never be allowed to fill to capacity instead being cleaned when approximately 25% full.
All traps need to be cleaned, maintained and serviced to make sure they are still performing effectively and doing the job they were designed to do. If you find that you’re cleaning and emptying interceptors far too often, you may need to reconsider whether your current installation is still suitable for your grease management needs – you may find that you need to upgrade.
Top Tips and Best Practises for Efficient Grease Management
Taking a proactive stand point in the fight against FOG is much preferred over a reactive response. You’ve taken the first step by installing a grease trap, next is to employ best practises for efficient grease management. By enforcing a few rules surrounding the control of fats, oils and grease in the kitchen, you can reduce the quantities being introduced to the drainage system and effectively deal with the FOG that does end up there.
Incorporate these actions into your current kitchen procedures;
There are many other good techniques for effective grease management however these are recommended as a good starting point.
For information regarding specialist cleaning contractors in your area contact your local authority.
