Hazardous area table.DOC

1

Rig floor and substructures

Bell nipple

outlet

Wellhead

N.A.

5   ft radius

10 ft radius

N.A.

Cellar, sunk ditches in zone 2

7,5m radius bell nipple, 9m below well head deck or to ground level, 7,5m above rig floor up to top windbreak  

N.A.

Enclosed spaces or semi-enclosed locations with source of hazard or spaces not separated by solid floor from the earlier mentioned spaces

Outdoor locations, within boundaries of the derrick, 3m above drill floor;  Semi-enclosed locations, below and contiguous to the drill floor, within boundaries derrick or to the extent of any enclosure which is liable to trap gas;

Outdoor location, below the drill floor and within the radius of 3m from a possible source of hazard such as the top of the drilling nipple;  Semi-enclosed derricks to the extent of their enclosure above the drill floor or to the height of 3m above the drill floor, whichever is greater

2

Mud tank

N.A.

Intermediate space:  level mud to top of tank

10 ft radius

N.A.

Enclosure around the tank

3m radius from opening tank and 3m radius from the top and sides of the tank extending to 7,5m on 0-3m ground level

Internal spaces tanks and pipes drilling mud, oil/gas/air mixture present for longer periods

Enclosed spaces containing mud circulation system with opening into space, between the well and final degassing discharge;

Outdoor and semi-enclosed locations the area within 1,5m radius from the boundaries of any opening to equipment part of the mud system, any ventilation outlets or access of/to zone 1 spaces (Except encl. /semi-encl.. spaces under the drill floor);

Pits, ducts or similar structures in locations which would otherwise be zone 2 which are so arranged that dispersion of gas may not occur

Enclosed spaces with open sections of the mud circulation system from final degassing discharge to the mud suction connection at the mud pit;

The areas 1,5m beyond the zone 1 areas, enclosed and semi-enclosed location under the drill floor

3

Mud ditch, trench or pit

N.A.

Intermediate space: level mud to top of tank

10 ft radius

N.A.

Below ground level with source of hazard;  Encl. Premises (without fire walls) without source of hazard in zone 2; Interior of the enclosure

7,5m radius surrounding space in open air;  Enclosed premises (with firewalls, etc.) without source of hazard in zone 2;  Naturally well ventilated conditions outside the limits of the derrick or mast zone may be reduced to 3m

N.A.

As part of the Mud system, the earlier described specifications, under the heading mud tank (MODU Code), are applicable

As part of the Mud system, the earlier described specifications, under the heading mud tank (MODU Code), are applicable

4

Mud pump

N.A.

-

-

N.A.

Not referred to in detail

Not referred to in detail

N.A.

As part of the Mud system, the earlier described specifications, under the heading mud tank (MODU Code), are applicable are still the same or valid

As part of the Mud system, the earlier described specifications, under the heading mud tank (MODU Code), are applicable are still the same or valid

5

Shale shaker

N.A.

5   ft radius

10 ft radius

N.A.

1,5m radius around the shale shaker

7,5m radius around the shale shaker

N.A.

As part of the Mud system, the earlier described specifications, under the heading mud tank (MODU Code), are applicable are still the same or valid

As part of the Mud system, the earlier described specifications, under the heading mud tank (MODU Code), are applicable are still the same or valid

6

Desander,  desilter or degasser

N.A.

-

5   ft radius

N.A.

Not referred to in detail

Not referred to in detail

N.A.

As part of the Mud system, the earlier described specifications, under the heading mud tank (MODU Code), are applicable

As part of the Mud system, the earlier described specifications, under the heading mud tank (MODU Code), are applicable

7

Degasser vent

N.A.

5   ft radius

10 ft radius

N.A.

Not referred to in detail

Not referred to in detail except for the vent.  If flow rates and type of effluent figures are not known, the zone should extend at least 15m radius