Bathroom Zones & IP Ratings Explained

Bathroom Zones - The IP Standard

The Ingress Protection (IP) Standard is a rating system for categorising electrical appliances by their ability to keep out foreign bodies, such as dust particles and water. For bathroom electronics, this is most relevant in preventing water from entering the appliance and causing a potentially dangerous malfunction. This system is now the standard in the UK and should be conformed to when designing and purchasing appliances for your bathroom.

Though potentially daunting, the IP rating is merely a reference system. Two numbers follow the letters IP, for example IP65. The first digit (0-6) refers to the object's protection against foreign bodies, such as dust and tools, while the second (0-8) is its ability to keep out water, from general humidity to complete submersion. The latter of these is more likely to be a concern in bathroom appliances, such as shower lights. There are a number of letter suffixes that can be added to the end of the IP code, signifying a wide range of other traits (for example, protection against oil).

The particle ratings are:

• 0: No protection against particles.
• 1: Protected against solid objects over 50mm, such as accidental touching with hands.
• 2: Protected against solid objects over 12mm, such as fingers.
• 3: Protected against solid objects over 2.5mm, such as tools.
• 4: Protected against solid objects over 1mm, such as wires.
• 5: Protected against non-harmful dust particles.
• 6: Protected against all dust.

The liquid protection ratings are:

• 0: No protection against water.
• 1: Protected against drops of condensed water, such as mist, while in an upright position.
• 2: Protected against drops of falling liquid while tilted slightly (up to a 15 degree angle).
• 3: Protected against rainfall while tilted further (up to a 60 degree angle).
• 4: Protected against splashing liquid from any direction.
• 5: Protected against jets of water, such as from a shower.
• 6: Protected against ship deck conditions, including waves of sea water.
• 7: Protected against submersion in water for a stated duration, up to 1m depth.
• 8: Protected against indefinite submersion in water.

While installing bathroom lighting and other electronics, this means that a liquid rating of 5 will be sufficient. This applies to our earlier example of IP65, where the appliance will be protected against jets of water, ideal for wall lights in a shower.

The bathroom can be divided into zones, based on proximity to the various water sources in that room. These zones are:

What are the UK Bathroom Electrical Zones?

Zone 0: Inside the bath or shower 

Bathroom Zone 0 is any area inside the bathroom that will be completely submerged in water, such as the interior of the bathtub or the shower basin. Electrical appliances installed in Zone 0 must meet a minimum rating of IPX7, ensuring they are completely protected against total water submersion.

Zone 1: Above the bath or shower

Bathroom Zone 1 is the area directly above the bath or shower tray, extending up to a height of 2.25 metres from the floor. Electrical appliances installed in Zone 1 must have a minimum rating of IP44 to protect against splashing water.

Zone 2: The 60cm perimeter

Bathroom Zone 2 is the area stretching 60cm outside the perimeter of Zone 1, as well as the 60cm radius surrounding any wash basin. Electrical appliances in Zone 2 must meet a minimum rating of IPX4 to ensure they are protected against mist and small water splashes from any direction.

Outside Zone

The Bathroom Outside Zone is any area within the room that falls completely outside the boundaries of Zones 0, 1, and 2. Electrical appliances in the Outside Zone do not require a specific IP rating by law, unless they are intentionally cleaned with streams of water. However, a minimum rating of IP44 is highly recommended to protect your electronics from ambient steam and condensation.

As an example, when browsing bathroom mirrors, you will notice that standard reflective glass doesn't require an IP rating. However, if you choose an illuminated mirror, it will usually carry a rating of IP44. This means it is safe for installation in a bathroom (such as Zone 2) but should not be subjected to direct water exposure. If a shower light has a rating of IP65, this means it is completely safe in an environment where it will be sprayed with water.

The IP rating removes any confusion by allowing a person to easily refer to a table and determine the suitability of an electrical appliance for any location in a bathroom. Where a product has an IP rating provided, HeatandPlumb.com lists it in the product details so you can be confident that it's safe before you make a purchase.