Library / GUIDE FOR THE ESTABLISHMENT AND OPERATIONS OF DOWNSTREAM GAS FACILITIES IN NIGERIA (LPG, CNG, LNG) ISSUED BY

GUIDE FOR THE ESTABLISHMENT AND OPERATIONS OF DOWNSTREAM GAS FACILITIES IN NIGERIA (LPG, CNG, LNG) ISSUED BY

Page 191 of 194

Applicable to all Oil & Gas Operators
GUIDELINES FOR THE ESTABLISHMENT AND OPERATIONS OF A GAS
RETICULATION FACILITY IN NIGERIA
Code: DPR Guide 0028 - 2020

Revision Date: 1st September 2020

26
hence reducing the potential for ruptures and collapses.
4.17.1 Internal Inspection of Storage tanks
1. The storage tanks shall be opened for internal inspection at intervals of not more than
60 calendar months in line with the MOSR, 1997 or subject to an approved Risk Based
Methodology.
2. For these inspections, tanks should be emptied and cleaned, and the inside examined
for holes and corrosion.
3. During the storage tank cleaning operations, adequate ventilation shall be provided
inside the tank and as work progresses, frequent tests shall be carried out to detect
any increase in gas concentration.
4. Adequate safety equipment and devices shall be provided for workers entering the
tank for their protection and survival in case of emergency while working in the tank.
5. The tanks shall be subjected to thorough visual and non-destructive test inspections
and Ultrasonic Thickness Measurement (UTM) of tank shells, roof, shall be carried out
and records made available on demand.
6. Any defect affecting the integrity and operability of the tanks observed shall be
repaired and or rectified.
4.17.2 Tank Entering
1. Only trained and qualified persons should conduct internal inspections. Under no
circumstances should anyone else enter the tanks.
2. No workman, without appropriate breathing apparatus, shall be allowed to enter a
hydrocarbon storage tank for cleaning or inspection unless it is free of hydrocarbon
and is continuously ventilated.
3. The tank shall be certified safe by a competent person and there must be strict
adherence to confined space entry procedure.