Stainless steel has established itself as the base material for furniture and equipment used in the food processing, cleanrooms and healthcare environments, for nearly all applications. This is predominantly because stainless steel has the ability to resist corrosion. In addition, its smooth, non-porous surface inhibits bacterial growth and makes it incredibly easy to keep clean and sterilise.
It is therefore the perfect material for designing hygienic furniture for these hygiene critical industries. In this guide we discuss the benefits in detail.
Stainless steel is corrosion resistant
Stainless steel resists corrosion from acidic or alkaline foods and from harsh cleaning chemicals used in the Food processing and Cleanroom / Pharmaceutical sectors.
The key to stainless steel’s corrosion resistance is due to its chromium content which forms a thin, invisible layer of chromium rich oxide; a passive protective layer which acts as a barrier, preventing the iron from reacting with oxygen and corroding. This protective layer will repair itself once any damage is removed and it is exposed to oxygen.
Different grades of austenitic stainless steel offer different levels of corrosion resistance. below we give details on common grades and their resistance.
304 grade
AISI 304 (Grade 1.4301) offers good overall corrosion resistance. It is able to withstand most cleaning and sterilisation routines without corroding including mechanical (high bar pressure), thermal (high temperature – up to 870C) and chemical (detergent with a chloride content up to 200 mg/l) cleaning.
304L
AISI 304L, L standing for ‘low carbon’ has a maximum carbon content of 0.030% compared to standard 304 which has a maximum carbon content of 0.07%. The low carbon content helps to ensure seamless welds to minimise the risk of harbouring bacterial or other contaminants.
316
AISI 316 (Grade 1.4401), has very similar hygienic qualities as 304 but due to its 2% Molybdenum content, it is more resistant to pitting corrosion. It can withstand chloride content of up to 500 mg/l and can withstand the most severe sterilisation regimes. It is therefore resistant to higher levels of chloride found in salt solutions, brines and some cleaning agents so is particularly suitable to use in the fish industry and pharmaceutical sectors.
Electropolishing
Additionally, electropolishing 304 or 316 stainless steel removals a very thin layer of the stainless steel surface to obtain a smoother surface (<0.3 RA versus <0.8 RA) to remove surface oxides and impurities, making it harder for bacteria to grow and form biofilms. By removing these microscopic pits and impurities, the smoother electropolished surface allows contaminants to be wiped away more easily and makes the disinfection process more effective and longer lasting.
Electropolishing reduces the number of particles that can come off the stainless steel surface due to normal wear and tear which is important for pharmaceutical cleanrooms where even tiny amounts of small particles can contaminate the products being produced. Therefore electropolishing 304 or 316 is the ideal hygienic solution for pharmaceutical companies, especially for grade B cleanrooms, to help maintain a sterile environment.
Stainless steel is strong and durable
Stainless steel is a robust, strong material that can withstand impacts and endure rigorous and demanding environments and so is inherently long-lasting and able to provide the hygienic design principles needed of furniture for the food processing and pharmaceutical / cleanroom environments.
Stainless steel is easy to clean
Its inertness gives the advantage of it being non-toxic. Its non-porous, non-absorbent surface helps to resist the accumulation of biofilms and so reduce the risk of creating a hygiene hazard. The smooth surface of stainless steel makes it easy and therefore quicker to clean and disinfect. The rougher the surface, the more food and micro-organisms will stick to the peaks and valleys across the surface. Any electropolished 304 or 316 stainless steel will have an even smoother surface due to its lower RA (roughness average) and therefore making it ideal for ultra-sterile environments.
Stainless steel is hygienic
In food and drink processing, medical, cleanroom and pharmaceutical companies, maintaining hygienic environments is of the utmost importance.
Due to the above hygienic advantages of 304 and 316 stainless steel hygiene teams are able to keep furniture clean and sterile. Used in combination with Teknomek’s hygienic design principles the furniture removes potential hiding places for bacteria and micro-organisms and therefore further reduces the risk of contamination. Our design principles also aid the cleaning process, making it easier and quicker to keep the furniture sterile.
Stainless steel is environmentally friendly
Stainless steel is 100% recyclable, and a high percentage of recycled scrap is used in its production. Around 60% of the global production of stainless steel makes use of recycled materials. This reduces its environmental impact and makes it an eco-friendly choice. When a product is no longer required, it can be easily melted down and recycled once again. Unlike certain other metals, such as aluminium, recycled stainless steel retains its quality and so is not limited in the applications to which it can be applied.
Stainless steel provides lifetime value
Its strength and robustness allow stainless steel products to be thinner than similar items made of lesser materials. Stainless steel can withstand impacts and so retain its shape and appearance for many years with correct handling, reducing repair costs. When looked at over the life of an item of furniture, its return on investment is extremely high.
