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ACO Thought Leader Feature


In the first of our Thought Leader features, Andy Buchan - Divisional Managing Director for UK-based ACO Building Drainage - explains why drainage should be such a key consideration for food and drink manufacturers, and why when it comes to hygiene the detail can make all the difference.

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Why is drainage so important?
Like so many things in life, if you want to achieve the right outcome you need to do the right things. Hygiene is undoubtedly a critical priority for any food processing facility but all too often key aspects of a building’s infrastructure such as the drainage system are at best considered as an afterthought and at worst not understood at all, even though they fall within the requirements of pre-requisite programmes under HACCP.

Thankfully recent research and best practice guidance from various bodies including the European Hygienic Engineering and Design Group (EHEDG) means the food and beverage industry increasingly recognises that poor hygiene can be caused as a direct result of bacteria that’s present in a facility’s drainage.

The potential migration of bacteria and the presence of harmful pathogens that may end up causing cross contamination are fundamental issues that need to be considered. Given that the data confirming the issue is readily available and the incidence of such problems is increasing it is no wonder that hygienic drainage is now seen as critical to any food manufacturing or processing facility whether you’re an international brewer or your business manufactures ready meals for a major supermarket.

There is still a very real need, however, to raise the profile of drainage and to increase awareness for the specification criteria that optimise hygiene, particularly with the increasing threats to public health caused by an ageing population, less resistance to infection and the increasing popularity of processed food.

What critical factors should food manufacturers and factory designers consider when planning drainage?
One of the key things to understand is that if you want to ensure good hygienic performance, you can’t afford to consider drainage in isolation. To ensure a good hygienic outcome in any food manufacturing or processing environment you need to take into account three core elements: Drainage, flooring and the importance of the correct cleaning protocols. To quote EHEDG, a leading source of independent best practice advice, “Drainage should be considered holistically from a site perspective as the site and each subsequent level of analysis has potential impact on hygienic operation.”

To optimise hygiene as well as health and safety, and operational costs it’s essential that the drainage, flooring and cleaning are compatible. At the very least, the drainage design needs to connect properly with the surrounding flooring to minimise the risk of bacterial contamination, your choice of flooring needs to be fit for purpose and both the drainage and flooring need to work practically with the pre determined cleaning protocols for the facility.

The cleaning protocol itself needs to be carefully considered. It should state what needs to be cleaned, how frequently it will be cleaned and how cleaning will physically be conducted – in short the chemicals and equipment you will use as well as the processes you will adopt.

If someone specifies a stainless steel drainage system, will that guarantee a good level of hygienic performance?
Stainless steel has long been the material of choice when it comes to the manufacture of drainage for hygiene-critical environments but that alone will not guarantee good hygienic performance. There’s a misconception that stainless steel is inherently clean but a more accurate statement is that stainless steel is cleanable – providing the drainage is hygienically engineered and designed. It is important that the drainage system is designed in such a way that it does not harbour pathogens, it is designed to be cleaned and where possible, is designed to ‘run dry’.

So what design features should a food or drink manufacturer specify in their drainage?
When it comes to delivering hygienic performance, the success is very much in the detail and more detailed specification criteria need to be considered. For example, does the application require you to use 304 or 316 grade steel, what surface roughness is required and is the surface fully pickle passivated? For readers who are not familiar with pickle passivation, it’s a process which is used to fully restore the all-important oxide film that naturally occurs on stainless steel but is destroyed on welded joints. Without this film, stainless steel ceases to be corrosion resistant and that can affect a product’s lifespan as well as creating hygiene risks.

The drainage system should also be designed in accordance with the best practice design principles of EHEDG. This affects both the functionality of the drainage and its ‘cleanability’ – an often overlooked consideration in the product selection process which can affect hygienic performance, employee health and safety, and ongoing operational costs.

EHEDG provides food and drinks companies with a wealth of best practice guidance compiled by leading experts from within the food industry and academia to help businesses optimise hygienic performance. For example, the guidance contained within the recently released ‘EHEDG Doc 44’ covers a comprehensive range of considerations with regard to the design and specification of building infrastructure including floors, ceilings and drainage. Additional guidance is also contained within EHEDG Docs 8 and 13 as well as BS EN 1672 and BS EN ISO 14159.

At the most basic level, ask yourself these questions: Is your drainage design fully drainable, has the welding been done in manner that minimises areas for bacterial growth, does your drainage have rounded corners with minimum radii of 3mm and can your drainage be cleaned without power-washing? Power-washing creates an aerosol spray of water that spreads bacteria previously contained within the drainage to the floors, walls and ceilings of a factory so it’s essential that your drainage can be properly cleaned without the need for power-washing.

What other benefits do food and drink manufacturers gain from specifying drainage that has been specifically designed to suit their requirements and manufactured to a high standard?
Although the main benefit is the optimisation of hygiene, a well designed and manufactured drainage system will also improve employee health and safety (reducing slips and trips), and because cleaning will be easier – and it’s likely to get done properly and potentially be required less frequently – result in a reduction in operational costs.

Is there anything else you would suggest food and drinks manufacturers do?
Basically think about and plan your drainage properly and importantly, do this as early in the project as possible. The most difficult area to resolve or perform maintenance on is the floor and drains. Almost all other elements of a factory can be changed or maintained without the closure of an area ultimately affecting capacity. So never under-estimate the impact drainage can have on the hygienic performance, health and safety, the operational costs of your business and ultimately your available capacity.

Make sure you specify a hygienically engineered and designed drainage system and ensure your choice of drainage design and the flooring future proofed. Food trends are changing rapidly in today’s market. In contrast, the infrastructure of a building and particularly areas such as floors and drainage are hard to change and having to do so can be both costly and disruptive. By considering these areas at the start instead of the end of the design process, food factory operators can save themselves a great deal of money and inconvenience in the longer term, and ultimately protect their businesses and brand reputations as well as public health.

So, where can food manufacturers go for further advice?
Working with a company which has a track record in the design and manufacture of hygienically engineered drainage systems for the food sector can also prove invaluable. Drainage companies which specialise in the development of hygienically engineered drainage for the food sector and which, like ACO, have expert in-house technical teams can provide the required level of specification advice and guidance. Working with them is perhaps the simplest way to ensure that every aspect of your drainage specification has been considered and that the drainage system you end up with meets your current and your future needs.


Biography: Andy Buchan, Divisional Managing Director, ACO Building Drainage
Having worked in ‘drainage’ for over 20 years Andy has a wealth of experience across a number of different material options including clay, plastics and concrete. Predominantly associated with manufacturing companies prior to ACO, Andy specialised in the development of new products, particularly within plastic pressure systems. He launched the famous Hep3O Water Pressure System and following market-leading research on the ‘failure mechanism of road ironwork’ the UK’s biggest selling manhole cover. Andy has worked in the UK and overseas in the USA & Europe and has covered both manufacturing and distribution focusing on a variety of sectors within the construction industry.