Understanding IP Rating Required Degrees of Protection for Electrical Equipment in Bathroom Zones

Understanding Required Degrees of Protection for Electrical Equipment in Bathroom Zones

Regulation 701.512.2 states:

"Installed electrical equipment shall have at least the following degrees of protection:

• (i) In zone 0: IPX7
• (ii) In zones 1 and 2: IPX4 This requirement does not apply to shaver supply units complying with BS EN 61558-2-5 installed in zone 2 and located where direct spray from showers is unlikely.

Electrical equipment exposed to water jets, e.g. for cleaning purposes, shall have a degree of protection of at least IPX5."

Regulation 701.32.2 - Description of Zone 0

Zone 0 is the interior of the bath tub or shower basin (see Figures 701.1 and 701.2).

For showers without a basin, the height of zone 0 is 0.10 m, and its surface extent has the same horizontal extent as zone 1 (see Figure 701.2(f)).

---

Regulation 701.32.3 - Description of Zone 1

Zone 1 is limited by:

• (i) the finished floor level and the horizontal plane corresponding to the highest fixed shower head or water outlet or the horizontal plane lying 2.25 m above the finished floor level, whichever is higher.
• (ii) the vertical surface:
  • (a) circumscribing the bath tub or shower basin (see Figure 701.1).
  • (b) at a distance of 1.20 m from the centre point of the fixed water outlet on the wall or ceiling for showers without a basin (see Figure 701.1(e) and (f)).

Zone 1 does not include zone 0.

The space under the bath tub or shower basin is considered to be zone 1. However, if the space under the bath tub or shower basin is only accessible with a tool, it is considered to be outside the zones.

---

Regulation 701.32.4 - Description of Zone 2

Zone 2 is limited by:

• (i) the finished floor level and the horizontal plane corresponding to the highest fixed shower head or water outlet or the horizontal plane lying 2.25 m above the finished floor level, whichever is higher.
• (ii) the vertical surface at the boundary of zone 1 and the parallel vertical surface at a distance of 0.60 m from the zone 1 border (see Figure 701.1).

For showers without a basin, there is no zone 2, but an increased zone 1 is provided by the horizontal dimension of 1.20 m mentioned in Regulation 701.32.3(ii)(b) (see Figure 701.1(e) and (f)).

The regulation specifies the protection levels required for electrical equipment in different areas (zones) within a bathroom, particularly against water ingress. The zones are defined based on their proximity to water sources, such as showers and bathtubs:

• Zone 0: This is the interior of the bath or shower itself. Equipment installed in this zone must have a protection level of IPX7, meaning it can withstand temporary immersion in water.
• Zone 1: This area includes the space directly above the bath or shower, up to a height of 2.25 meters from the floor. Electrical equipment here must have a protection level of IPX4, which means it is protected against splashing water from any direction.
• Zone 2: This zone extends 0.6 meters beyond Zone 1 and up to a height of 2.25 meters. Similar to Zone 1, electrical equipment in Zone 2 must also be protected to IPX4.
• Exceptions: Shaver supply units that meet the standards of BS EN 61558-2-5 and are installed in Zone 2 where direct spray from showers is unlikely are exempt from these requirements.
• Special Case: Electrical equipment that is exposed to water jets, such as those used for cleaning, must have a protection level of at least IPX5. This ensures that the equipment is protected against water projected from a nozzle.

Frequently Asked Questions

Q: What does IPX7 mean?

A: According to Regulation 701.512.2, IPX7 indicates that the electrical equipment can withstand immersion in water up to 1 meter for 30 minutes. It is crucial for equipment in Zone 0, where it may be submerged in water.

Q: What is the difference between IPX4 and IPX5?

A: IPX4 means the equipment is protected against water splashes from any direction, suitable for Zones 1 and 2. IPX5, on the other hand, means the equipment is protected against water jets projected from a nozzle, which is necessary for areas where cleaning with water jets is common. This is specified in Regulation 701.512.2.

Q: Are there any specific standards shaver supply units must comply with?

A: Yes, Regulation 701.512.2 states that shaver supply units in Zone 2 must comply with BS EN 61558-2-5 and be located where direct spray from showers is unlikely to be exempt from the IPX4 requirement.

Q: Why are different IP ratings required for different zones?

A: Different zones in a bathroom have varying levels of exposure to water. The IP ratings ensure that electrical equipment is sufficiently protected against the specific water exposure it may encounter, thereby enhancing safety, as outlined in Regulation 701.512.2.