Stainless Steel, Silicone or Membrane? Choosing a Rugged Keyboard

We get a lot of enquiries that start with "I need a rugged keyboard" and very little else. That is completely understandable, but "rugged" covers a huge range of products. A keyboard that is perfect for a food factory washdown area would be the wrong choice for a public kiosk, and a keyboard built for a ship's bridge would be overkill on a warehouse packing bench.

The RUGGED range is a good example. It includes stainless steel, silicone rubber and sealed membrane keyboards, in desktop, panel mount and OEM formats, with touchpads, trackballs and backlighting as options. This guide explains the main differences so you can narrow it down before you get in touch.

Start with the environment, not the keyboard

Before looking at models, it helps to answer four questions:

1. What will get on it? Water, oil, dust, food, chemicals, disinfectant, or just the odd spilt drink.
2. How will it be cleaned? A quick wipe, a spray of disinfectant, or a full hose-down.
3. Who will use it? Trained staff who look after it, or members of the public who might not.
4. How will it be mounted? On a desk, built into a panel or kiosk, or integrated into your own equipment.

Those answers point you towards the right material and the right IP rating far more reliably than any spec sheet.

A quick word on IP ratings

IP ratings come from the international standard IEC 60529, and the IEC's own guide explains them well. The first digit is protection against solids such as dust, and the second is protection against water. In practice, for keyboards:

• IP65 is dust tight and protected against water jets. Fine for wipe-down and splash environments.
• IP67 is dust tight and protected against temporary immersion. A good choice where keyboards are cleaned with a lot of water.
• IP68 is dust tight and protected against continuous immersion, to conditions set by the manufacturer. This is the level for hygienic and washdown areas.

You will also see the RUGGED range describe ratings as "static" or "dynamic". As the range uses it, a dynamic rating applies while the keyboard is being used, whereas a static rating applies to the keyboard at rest, typically from the front once it is panel mounted. If the keyboard will be cleaned or splashed while people are typing on it, a dynamic rating is the one to look for.

Stainless steel keyboards: for public and high-abuse areas

Stainless steel keyboards are the tough option. They are vandal resistant, they do not mind being hit, and they look at home in kiosks, ticket machines, help points, prisons, laboratories and factories.

A few examples from the range:

• The SSK-PC-D is a 66-key stainless steel panel mount keyboard with a 38 mm stainless steel trackball, aimed at kiosk, public access and industrial use.
• The RKB-A361TP-FN-DWP is an 83-key stainless keyboard rated IP67 dynamic and washable, with a sealed touchpad.
• The RKB-A420TP-KP-FN-DWP gives you a fuller 104-key layout in stainless steel, again IP67 dynamic and washable.

The trade-off is feel. Stainless keyboards use short-travel keys, so they are not as comfortable for long typing sessions as silicone or a standard office keyboard. For short bursts of data entry, they are ideal.

Silicone rubber keyboards: sealed, washable and comfortable

Silicone keyboards are moulded as a single sealed sheet, which means there are no gaps around the keys for dirt or liquid to get into. They are easy to clean, quiet, and much nicer to type on for long periods than metal.

This is the type we usually recommend for healthcare, food production, laboratories and anywhere that hygiene matters. It is also what many military and vehicle keyboards are based on, including the iKey models we cover in our posts on NHS keyboards and in-vehicle keyboards.

• The RKB-M390TP-KP-FN-DT is a 108-key silicone hygienic keyboard, IP68 dynamic, with a numeric pad and a sealed touchpad.
• The RKB-M275-OTB-FN is a 92-key IP68 silicone keyboard with a washable 16 mm optical trackball built in.
• The RKB-M460TP-KP-FN-BL is a 106-key IP65 industrial and military keyboard with adjustable backlighting and a touchpad.

Sealed membrane keyboards: full layouts at a sensible cost

Membrane keyboards use a flat, sealed overlay over the key switches. They are very easy to wipe clean and can be made to high IP ratings while still giving you a full layout with a numeric pad. They are a popular choice for control rooms, industrial workstations and cleanrooms where you want a proper keyboard without the cost or weight of stainless steel.

• The RKB-D396TP-KP-FN-DT is a 108-key desktop membrane keyboard rated IP68 dynamic and washable, with a sealed touchpad.
• The RKB-D410-TB-KP-FN is a 108-key IP65 panel mount membrane keyboard with an IP68 washable 38 mm trackball.

Touchpad or trackball?

Most of the range is available with either, and it is worth thinking about. Touchpads are flat and easy to clean, which suits hygienic areas. Trackballs give more precise control and work better with gloves, which is why they are common in industrial, marine and defence consoles. If the keyboard is in a public area, a stainless steel trackball is very hard to damage.

When none of them quite fit

Quite often a customer needs something slightly different: a particular layout, extra function keys, a specific connector, a legend in another language, or a keyboard to fit an existing cut-out. Much of the RUGGED range is available in OEM and custom versions, and that is often the quickest route to getting exactly what you need.

The RUGGED range is supplied and supported through our partner Rugged Limited, a UK specialist that has been supplying and customising rugged keyboards for 25 years. Custom layouts and OEM versions are handled with them.

Get a recommendation

If you are not sure which way to go, tell us about your application and we will suggest a shortlist and a quote. We usually reply within 24 hours. You can also browse our stainless steel and metal keyboards, washable and sealed keyboards and panel mount keyboards.