Part 7 of the IEE Wiring Regulations deals with special installations and locations. Section 701 specifically addresses locations containing baths or showers. It defines three zones - Zone 0 inside the bath/shower, Zone 1 extending to the edge of the bath/shower, and Zone 2 extending 60cm beyond Zone 1. Additional protection through 30mA RCDs is required for all circuits in locations with baths/showers. Various protective measures like automatic disconnection, SELV/PELV, and electrical separation are permitted.

1. Requirements for Electrical Installations IEE Wiring Regulations 17 th Edition Part 7

2. IEE Wiring Regulations 17 th Edition - Part 7 700 General 701 Bathrooms 702 Swimming pools etc 703 Saunas 704 Construction sites 705 Agricultural 706 Conducting Locations 708 Caravan Sites 709 Marinas 711 Exhibition show stands 712 Solar Voltaic units 717 Mobile Units 721 Caravans 740 Temporary installations, amusements, fairs etc There are now 14 “special locations” – one has been split into two and there are five new ones, one of which has been threatened for some years

3. Requirements for Electrical Installations IEE Wiring Regulations 17 th Edition Part 7 Special installations or locations

4. PART 7 SPECIAL INSTALLATIONS or LOCATIONS The particular requirements for each section in part 7, supplement or modify the general requirements contained in other parts of the “Regs”

5. PART 7 SPECIAL INSTALLATIONS or LOCATIONS This part is unique in regard to the numbering system - - - - The first three numbers indicate the SECTION The numbers that follow indicate where, in the previous sections, information can be located regarding the section.

6. PART 7 SPECIAL INSTALLATIONS or LOCATIONS e.g. 709.553.1.13 This is the section – Marinas and Similar Locations This bit refers to the section in Part 5 (553) ACCESSORIES And this is the regulation, or series, regarding PLUGS & SOCKET-OUTLETS

7. PART 7 SPECIAL INSTALLATIONS or LOCATIONS You will get used to it as we proceed! It will make sense Let us make a start by looking at - - - - - -

8. Section 701 LOCATIONS CONTAINING A BATH OR SHOWER

9. Section 701 LOCATIONS CONTAINING A BATH OR SHOWER Such locations and the surrounding area are considered to be locations where there is an increased risk of electric shock due to: a reduction in body resistance caused either by bodily immersion or by wet skin, absence of or minimal clothing, & likely contact of substantial areas of the body with earth potential.

10. Section 701 LOCATIONS CONTAINING A BATH OR SHOWER “Zonal” concept is based on the perceived risk of electric shock in relation to areas in/around the bath etc Having established the zones, particular requirements are then prescribed for: switchgear, controlgear, accessories, and current using equipment.

11. Section 701 LOCATIONS CONTAINING A BATH OR SHOWER The zones as they are now - - - ->

12. There are now only 3 zones Zone 0 – inside the bath Zone 1 – to the edge of the bath Zone 2 – next to the bath Section 701 LOCATIONS CONTAINING A BATH OR SHOWER

13. Zone 0 - is the interior of the bath or shower basin (see diags. In BS 7671) For showers without a basin, the height of zone 0 is 0.10m and its surface extent has the same horizontal extent as zone 2 (see diags.) Section 701 LOCATIONS CONTAINING A BATH OR SHOWER Description of the zones

14. Section 701 LOCATIONS CONTAINING A BATH OR SHOWER Description of the zones Zone 1 - is limited by: The finished floor level and the horizontal plane corresponding to the highest fixed shower head or water outlet or the horizontal plane lying 2.25m above the finished floor level, whichever is the higher. The vertical surface: Circumscribing the bath tub or shower basin At a distance of 1.2m from the centre point of the fixed water outlet on the wall or ceiling for showers without a basin

15. Section 701 LOCATIONS CONTAINING A BATH OR SHOWER Description of the zones 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 the greatest (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 diagram BS 7671) For showers without a basin, there is no zone 2 but an increased zone 1 is provided by the dimensions of 1.20 m as mentioned in reg. 701.32.3(ii)b (see Fig 701.1(e) and (f) in BS 7671).

16. Section 701 LOCATIONS CONTAINING A BATH OR SHOWER 701.411.3.3 Additional protection by RCDs Additional protection shall be provided for ALL circuits of the location, by the use of one or more RCDs having the characteristics in regulation 415.1.1 Note: see also regulation 314.1(iv) and 531.2.4 concerning the avoidance of unwanted tripping ≤ 30 mA RCD protection is required for all circuits of the location NOW MAKE YOUR OWN MIND UP

17. Section 701 LOCATIONS CONTAINING A BATH OR SHOWER Protective measures The basic protective measures permitted for use in a room containing a bath or shower are: Automatic disconnection of supply SELV or PELV Electrical separation

18. Section 701 LOCATIONS CONTAINING A BATH OR SHOWER 701.415.2 - Additional protection by supplementary bonding Not necessary where all circuits of the location: comply with requirements for automatic disconnection are ≤ 30 mA RCD protected, and all extraneous-conductive-parts of the location are connected to the protective equipotential bonding within the installation

19. Section 701 LOCATIONS CONTAINING A BATH OR SHOWER Protective measures – SELV and PELV SELV and PELV Circuits Basic protection shall be provided by either: Basic insulation complying with Regulation 416.1, or Barriers or enclosures affording a degree of protection of at least IPXXB or IP2X

20. Section 701 LOCATIONS CONTAINING A BATH OR SHOWER Protective measure – Electrical separation Electrical separation (one item of equipment only) in use where no earth return path is available on the secondary side of the transformer

21. Section 701 LOCATIONS CONTAINING A BATH OR SHOWER Shaver supply units to IEC 61558-2-5 utilize the protection measure electrical separation. 230 V from earthed supply 230 V (unearthed supply)

22. Section 701 LOCATIONS CONTAINING A BATH OR SHOWER External influences – Overview of IP codes Zones Minimum degree of protection IP Code Zone 0 IPX7 Zone 1 and 2 general IPX4 Zones 1 and 2 Where water jets are likely to be used for cleaning purposes in communal baths or communal showers IPX5 Outside zones 0,1, and 2 General rule

23. Section 701 LOCATIONS CONTAINING A BATH OR SHOWER 701.753 – Electric floor heating Where installed in a room containing a bath or shower all heating cables must be of a type incorporating: a metal sheath, or metal enclosure, or fine mesh metallic grid NOTE: In all of the above cases, the metallic sheath, enclosure or grid must be connected to the supply protective conductor (unless SELV

24. Section 701 LOCATIONS CONTAINING A BATH OR SHOWER A typical electric floor heating application