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Applicable to all Oil & Gas Operators GUIDELINES FOR THE DESIGN, CONSTRUCTION, OPERATION AND MAINTENANCE OF OIL AND GAS PIPELINE SYSTEMS IN NIGERIA Code: DPR Guide 0027 – 2021

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Applicable to all Oil & Gas Operators  
GUIDELINES FOR THE DESIGN, CONSTRUCTION, OPERATION AND 
MAINTENANCE OF OIL AND GAS PIPELINE SYSTEMS IN NIGERIA  
Code: DPR Guide 0027 – 2021 
 
Effective Date: 14th October 2021 
 
This is a property of the Department of Petroleum Resources. All rights reserved  
 
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specified construction types of pipelines in the proximity of main roads and 
railroads and the mode of their crossing shall be complied with. 
d. The minimum depth of burial shall be as specified in Section 3.3.1 but where these 
minimum depths could not be achieved, the pipeline at these points shall be 
encased, bridged, or specially reinforced to withstand any anticipated external 
load. 
e. There shall be a minimum clearance of 0.5 meter between the pipeline and any 
other underground structure not connected with it. 
f. It shall be mandatory for all buried pipelines to be protected against corrosion 
where any pipeline is to transport corrosive or toxic gas, the following shall be 
ensured: 
i. 
 Design parameter shall be such that the gas pressure at any time in the 
pipeline shall not result in a hoop stress greater than 60 percent of the 
specified minimum yield strength of the pipeline material based on the 
nominal wall thickness.  
ii. 
Block valves and check valves shall be so located as to prevent the escape 
of the corrosive or toxic gas into the atmosphere in the event of a pipeline 
failure. 
g. The design, installation and maintenance of the associated corrosion control 
system of the pipeline shall be in line with section 3.5, in conformance with to the 
provisions of NACE SP0169-2013 and other internationally recognised standards 
approved by DPR. 
4.2.2 Requirements for Inspection and Testing of Gas Pipelines  
i. 
Inspection of pipeline construction materials and its appurtenances, welding, 
ditching, stringing and the general installation shall follow the procedure outlined 
in chapter IV of the ASME B31.8-2018 and other internationally recognised 
standards approved by DPR. 
ii. 
All gas pipelines laid in farmlands, virgin areas and sparingly populated areas shall 
be tested with water up to a minimum pressure of 125 percent of their maximum 
operating pressure or with air up to 110 percent of their maximum operating