When a requirements specification is being written and before an electrical enclosureis constructed, an IP rating must be assigned. This will be determined in accordance with various factors, such as the type of equipment to be protected, the required operating conditions including environmental considerations, the level of hazard or risk, and other details affecting required performance.

It is very important that you get the IP rating of your enclosure right, otherwise any failure or risk arising as a result could not only be dangerous to the health and safety of service engineers working on the equipment, but also potentially damage the contents of the enclosure. Failure of this equipment might disrupt a key systems function and cause a major highways incident.

In order to prevent this from happening, you need to understand the regulatory requirements and specifications surrounding IP ratings and whose responsibility it is to adhere to them.

What are the regulations surrounding IP ratings?

The British Standards Institution (BSI) sets standards and provides regulatory guidelines for manufacturing electrical enclosures. One of the main specifications that should be adhered to is BS EN 60529:1992, which provides guidance on how electrical enclosures must be sealed effectively against any kind of intrusion.

However, the standards that you should use will differ according to the type of electrical enclosure that is being designed, as the equipment being contained plays a fundamental part in determining the IP rating.

A critical step in ensuring that a cabinet is fit for purpose is to test it. This stage cannot be ignored and the BSI publishes documentation standards that outline which tests are mandatory for a particular enclosure. A cabinet designed for a highway or motorway environment, for example, is most commonly rated to at least IP56 and will need to be TR100 approved. (Link to highway enclosure blog here, when it is up.)

Who is responsible for IP ratings?

In the UK, it is the designer or specifier’s responsibility to provider the manufacturer with the correct IP rating for an enclosure.

Only someone with a thorough knowledge of the equipment’s characteristics and operating requirements can make this decision. They need to know what the equipment will tolerate without being damaged, for example water and solid particle ingression, moisture and humidity levels, temperature changes and more. The location of the enclosure will also need to be factored in, as an enclosure placed on a bank or a road cutting may be exposed to lashing by wind-driven rain, or very deep snow. An enclosure closer to the highway may be deluged with exceptional splashes of water from the passing of heavy vehicles.

Based on these considerations, once the specification for the enclosure is provided, it is the manufacturer’s responsibility to ensure that it is designed, tested and made to be compliant with the prescribed standard. That company may also provide subsequent installation and maintenance, again ensuring relevant standards are met.

If an enclosure is given the wrong IP that proves to be inappropriate, it may become evident at the testing stage. If, for whatever reason, it proceeds past this stage, is installed and fails in use, the penalties that an operating company or manufacturer might face are severe.

It could be especially detrimental depending on the equipment your enclosure is hosting. As touched on before, if it is linked to critical services or systems, such as traffic signage on a busy motorway, for example, the consequences might not be minor. What’s more, if there’s any risk of harm to others, you could be landed with large fines and even imprisonment as a result of health and safety breaches. It’s therefore in your best interest to ensure that the IP rating is specified correctly, and that your manufacturer can provide you with a high quality and compliant enclosure.

Whilst responsibility lies with the manufacturer to provide you with a compliant product, in order to avoid choosing the wrong supplier and electrical enclosure, as well as incur additional costs to your organisation as a result of that, you should yourself have knowledge of IP ratings. This will help you not only understand your own needs better, but will also allow you to audit a manufacturer more thoroughly as you will have some knowledge of your own.

At ICEE we will work with a customer, advising and ensuring that – based on the specification and the conditions of use described by the customer – the enclosure will have the right IP rating and be compliant. We have been providing customers with professional enclosures for over thirty-one years, built only with the highest quality materials and with safety and compliance in mind.

To help you, we have created a comprehensive chart that covers how to read an IP rating and gives examples of the most commonly used ones for enclosures in various settings, such as the highways and underground railways sectors. Download a free copy below.