---
title: Fixed Equipment in Zones 1 and 2
description: "IEC 60079-14 specifies the cable requirements for fixed equipment in Zone 1 & 2. Cables sheathed with thermoplastic, thermosetting or elastomeric (“rubber-like”) material may be used in fixed wiring installations. Generally, they should be circular and effectively filled, with extruded…"
url: "https://www.eicstech.com/kb/wiring-systems-installation/fixed-equipment-in-zones-1-and-2/"
updated: "2022-06-02"
category: "Explosion Proof Basics / Wiring Systems & Installation"
---

# Fixed Equipment in Zones 1 and 2

IEC 60079-14 specifies the cable requirements for fixed equipment in Zone 1 & 2.

Cables sheathed with thermoplastic, thermosetting or elastomeric (“rubber-like”) material may be used in fixed wiring installations. Generally, they should be circular and effectively filled, with extruded bedding. Any filler must be non-hygroscopic.

Mineral insulated metal sheathed cable is suitable for use in hazardous areas.

Cables are normally armoured, but non-armoured types may be used if mechanically protected.

Cables commonly used in the offshore industry are EPR/CSP with **braided wire armour**, although XLPE/LSF **single wire armoured (SWA)** types may be found on fixed platforms. PVC or XLPE/SWA/PVC is often used in land installations.

Copper conductors may be used for all sizes of cables, but **Aluminium conductors** must have a cross-sectional area **not less than 16mm^2**, and be connected via suitable terminals.

Examples of the various permitted cable insulation types are given in the table below.

## Elastomeric

| Chlorosulphonated polyethylene | CPS |
| --- | --- |
| Cross-linked polyethylene | XLPE |
| Ethylene propylene rubber | EPR |
| Ethylene vinyl acetate | EVA |
| Natural rubber | NR |
| Polychloroprene | PCP |
| Silicone rubber | SR |

## Thermoplastic

| Polyethylene | PE |
| --- | --- |
| Polypropylene | PP |
| Polyvinyl chloride | PVC |

## **Cables in Zone 0**

These would usually be screened cables connected to intrinsically safe ‘ia’ equipment and must withstand a 500Vac or 750Vdc test between conductor to earth, conductor to screen, and screen to earth. Minimum conductor or conductor strand size is 0.1mm^2.

## **Elastomeric Cables**

A typical elastomeric cable comprises EPR insulated copper conductors and CSP inner and outer sheaths (which are heat and oil resistant and flame retardant **(HOFR).** Operating temperature range is 30°C – 90°C.

![](https://www.eicstech.com/wp-content/uploads/2022/06/HOFR.png)
HOFR Cable Examples used in Hazardous Zone

A fire resistant LSF cable is illustrated below:

![](https://www.eicstech.com/wp-content/uploads/2022/06/LSF-Cable-used-in-EX-Zone.png)

## **Insulation colour**

The internationally agreed L.V. colour code is now:

- **Phases:** brown, black, grey (3 x brown may be used in some circumstances)
- **Neutral:** blue
- **Protective earth conductor:** green/yellow

Cables, particularly offshore types, may be encountered with other colour codes.

**Where cables of different colour codes are joined or connected together, they must be properly marked to avoid confusion.**