Sim's Electrical Companion
IP - International Protection Ratings
Ingress Protection Against Solid Foreign Bodies, Liquids & Additional Specific Factors
International protection ratings have two numbers and sometimes a letter at the end. The first number is protection against the ingress of solid foreign bodies.
The second number is protection against liquids.
The letter is to denote some further specific field of protection. If an X is present e.g. IP2X it means that was not tested.
Common Applications of IP Ratings
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All standard equipment must provide a degree of basic protection against electric shock. The application of insulation to prevent accidental contact of a live part. For the top surface of all items have to comply to IP4X or IPXXD which will prevent access by a >1mm diameter wire. All sides and bottoms of the containment must comply to IP2X or IPXXB cannot access a live part with an object 80mm log 12.5mm wide and hinged in two places. E.g. A simulated child’s finger.
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Special Locations
BS 7671 Requirements Part 7 specifies IP ratings for equipment that is more prone to damage by liquids or solids from its environment.
This non-exhaustive list includes some of the locations specified.
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Locations Containing a Bath or Shower
Zone 0 is in the bathtub, sink or shower tray - any installed equipment must be ≤ 12V Separated Extra Low Voltage (SELV) and be at least IPX7
Examples of this application include TV, radio lights and pumps in whirlpool tubs or hot tubs.
Zone 1 is within 60 cm of the bath, shower basin or 1.2m away from the outlet of a shower with no basin and to a fixed height of 2.25m or the height of the shower head whichever is greater. In zone 1 SELV sockets and outlets may be used (Separated from earth <25V) and any equipment that is designed for this purpose as specified by the manufacturer. This departure from BS 7671 allows manufacturers to be responsible for the safety of the electrical installation with regard to loads in the zones. Equipment that fits into this category would be electric showers, pumps & radiators etc. All equipment must comply with the requirements to achieve at least IPX4. IPX5 recommended if the area is to be cleaned with jets or a shower hose.
Swimming Pools and Other Basins
Zone 0 - In the pool, spa and anywhere in line of or below water jets or fountains all installed equipment to be IPX8 and SELV <25V with the source of the SELV outside the zones. Fountains and jets require additional protection by either electrical separation or RCD <30mA.
Zone 1 - Outside of zone 0; horizontally 2m from the basin edge and vertically 2.5m above the basin water level all equipment to be IPX4 or IPX5 if jets are used for cleaning.
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Rooms and Cabins Containing Sauna Heaters
Zone 1 - 0.5m from the edge of the heater and the space above it. Requirements be that only the heater and components belonging to the heater be installed in that zone as specified ultimately by the manufacturer. All equipment must be IPX4 or IPX5 if jets are used for cleaning.
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Agricultural and Horticultural Premises
ALL equipment of the electrical installation shall have a minimum degree of protection of IP44 or IP XXD. Where IP 44 is not available as an option the equipment must be sited in a container that is IP44.
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Marinas & Similar Locations
Equipment installed on or above a jetty wharf potoon shall be at least IP3X. Anything that may be splashed IPX4; Anything that may experience jets of water IPX5 and anything that may suffer waves IPX6.
External Influences
Construction Products Regulations (CPR)
All cables designed for use in fixed electrical installations now need to undergo an additional test to check their resistance to fire. All cables must now have a fire classification code. Details of this classification as well as compliance with its individual CE or BS standard should be made available on a material data sheet known as a Declaration of Performance (DOP).
Information Presented on the Declaration of Performance:
Type of cable Manufacturer Serial / batch number Manufacturer address
DoP number System of assessment Test lab details Level of fire performance
Date of issue Manufacturer signature Name and number of notified body
External Influences
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Cables are classified by three factors (A) Environmental, (B) Utilisation and (C) Building type.
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Environment is further broken down to the following factors: (AA) Air temperature, (AB) Temperature and humidity, (AC) Altitude, (AD) Presence of water, (AE) Presence of solid foreign bodies, (AF) Corrosion, (AG) Impact, (AH) Vibration, (AJ) Other mechanical stresses, (AK) Flora, (AL) Fauna, (AM) Electromagnetic effects, (AN) solar radiation, (AP) Seismic activity, (AQ) Lightning, (AR) Air movement and (AS) Wind.
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Utilisation is broken down to capability of the persons using the system (BA), consideration is being given to the (BB) Resistance of the human body (Not currently specified), (BC) Persons contact with earth, (BD) Ease of evacuation (BE) Nature of processed or stored materials and any risk associated with that.
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Buildings takes into account the materials the building is constructed with and the nature of its structure.
The designer of an electrical installation should consider if any of these factors need to be taken into account. Part 7 of BS 7671 (Special locations) defines what external influences need to be taken into account with regard to the installation. Example in marinas subject to the effect of waves the classification is AD6 which specifies all installed equipment must be IPX6 of higher or installed in a container that is IPX6. If there is any doubt refer to manufacturer's instructions and BS 7671 for guidance.