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Flanged Pipework -All flanges in a Hydrocarbon filled system generate a 3 meter Zone 2 around them

10 Metres

ZONE 2

ZONE 2

ZONE 1

4.5 Metres

3 Metres

4.5 Metres

3 Metres

3 Metres

3 Metres

A Guide to Zoning

Zone 0 - Area where explosive gas-air mixture is continuously present or present for long timesZone1 - Area where explosive gas-air mixture is likely to occur in normal operationsZone 2 - Area where and explosive gas-air mixture is not likely to occur, and if it occurs, it will only exist for a short timeSafe Area - All other areas than those mentioned above

4.5 Metres

Separator sometime get classed as Zone 0 but it does not have electrical or temperature sources to produce ignition. The Separator does produce a Zone 2 area due to infrequent releases from Daniels box, Sight glass etc.Everything within 3 metres horizontal and 4.5 metres above and below must be rated Zone 2. This means Pump drivers and lights if we install them on the skid.

Steam Heaters are not a problem but the Steam Generator needs to be remote as this is an open flame diesel burner. You do need safety devices to protect from Coil failure from reaching the Steam Generator..Gas or Diesel Fired Heaters have the fire tube and the exhaust stack can be classed as Zone 2 if all safety devices are in place. Flame arrestor on Fire Tube, Low water alarm, ESD on the Shellside and Spark Arrestor on the Exhaust.

Zone 2

Zone 2

Zone 2

PumpsElectric Pumps as long as they are fitted with a Zoned classified motor and starter box all is ok.Diesel Pumps Safety devices required - Anti Static Belts; Anti Static Fan for the radiator; Spark Arrestor on the Exhaust; Shutdown on air intake; water cooled exhaust for surface temp need to cool to 200f, this means an oversize radiator. No way should a diesel pump operate in Zone 0

Zone 2

Companies and countries vary Zone Classification this is only a general guide

Pressurized Tanks - Same as Separators

Labs -Lab Electrics should have the relative Zone Classification fitted however the computer equipment is not able to meet this. To overcome this the Lab should be fitted with -Air Purge System; Internal Cabin Pressure Sensors/Shutdowns; Internal LEL/HEL (Lower,Higher Explosive Limit) and H2S Sensors ;Alarm and Time delay shutdowns for open doors; Multi Cable Transit (MCT) -MCT is used for feeding Scan cables to the lab and form a compression seal around the cables.

Compressors- Never in Zone 0 Avoid Zones 1 & 2 if at all possible unless proper safety devices are fitted. If in doubt place in a Safe Zone

Trees and Rig floor are usually considered zone I

3 Metres

3 Metres

3 Metres