English to French Tech/Engineering Petroleum Eng/Sci FIRED HEATER AND ASSOCIATED COMBUSTION AIR SYSTEM

5 DESCRIPTION OF FIRED HEATER AND ASSOCIATED COMBUSTION AIR SYSTEM
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5.4 Equipment Handling Arrangements
5.4.7 Observation Doors at Various Elevations

A total of six observation doors (OBS doors) are provided at the radiant section of the heater. Four of these are at an elevation of 4793mm from ground level two are at an elevation of 8750mm from ground level.
The size of the doors is 130mm × 190mm.

A ***hearth platform*** at an elevation of 3395mm provides access to the doors situated at an elevation of 4793mm.

The platform installed at elevation 7500mm permits access to the doors at elevation 8750mm.

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