The equipment marking must be to IEC 60079-2 & IEC 60079-0, and contain the following information:
- The manufacturers name
- Model number, type and serial number
- The symbol Ex, followed by the pressurisation types i.e. pxb, pyb, or pzc
- The gas group symbol II, temperature class, or the maximum surface temperature, or both, e.g. T3, or 200°C, or 200°C (T3)
- The certificate number
- The internal free volume excluding the ducts
- The protective gas (when a gas other than air is used)
- Details of the minimum purge requirements
- The minimum and maximum permissible over-pressure
- The minimum flow of protective gas
- The min. and max. supply pressure to the system
- The maximum leakage rate from the enclosure
- The temperature or temperature range of the safe gas at the inlet duct
- The point(s) where the pressurisation is to be monitored.
IEC 60079-17:2013 Table 3
Inspection schedule for Ex “p” and Ex “pD” installations
| Check that : | Grade | of | inspection | |
| X = required | ||||
| A | EQUIPMENT | D | C | V |
| 1 | Equipment is appropriate to the EPL/Zone requirements of the location | X | X | X |
| 2 | Equipment gas group is correct | X | X | |
| 3 | Equipment temperature class or surface temperature is correct | X | X | |
| 4 | Equipment circuit identification is correct | X | ||
| 5 | Equipment circuit identification is available | X | X | X |
| 6 | Enclosure, glasses and glass-to-metal sealing gaskets and/or compounds are satisfactory | X | X | |
| 7 | There are no unauthorised modifications | X | ||
| 8 | There is no evidence of unauthorised modifications | X | X | |
| 9 | Lamp type, rating and position are correct | X | ||
| B | Installation | |||
| 1 | Type of cable is appropriate | X | ||
| 2 | There is no obvious damage to the cable | X | X | X |
| 3 | Earthing connections, including any supplementary earthing bonding connections, are satisfactory, for example connections are tight and conductors are of sufficient cross-section | X | X | X |
| Physical check | X | X | X | |
| Visual check | X | X | X | |
| 4 | Fault loop impedance (TN systems) or earthing resistance (IT systems) is satisfactory | X | ||
| 5 | Automatic electrical protective devices operate within permitted limits | X | ||
| 6 | Automatic electrical protective devices are set correctly | X | ||
| 7 | Protective gas inlet temperature is below maximum specified | X | ||
| 8 | Ducts, pipes and enclosures are in good condition | X | X | X |
| 9 | Protective gas is substantially free from contaminants | X | X | X |
| 10 | Protective gas pressure and/or flow is adequate | X | X | x |
| 11 | Protective and/or flow indicators, alarms and interlocks function correctly | X | ||
| 12 | Conditions of spark and particle barriers of ducts for exhausting the gas in hazardous area are satisfactory | X | ||
| 13 | Specific conditions of use (if applicable) are complied with | X | ||
| C | ENVIRONMENT | |||
| 1 | Equipment is adequately protected against corrosion, weather, vibration and other adverse factors | X | X | X |
| 2 | No undue accumulation of dust and dirt | X | X | X |
