Protection
Before entering any tank or equipment, it is necessary to take certain special safety-precautions. Refer to site safety procedures.
Inspect through available openings overhead parts for loose purlins, or any other object which might fall and cause personal injury. If nitrogen blanketing is foreseen on a tank the best internal protection will be obtained by applying the blanket soonest.
The following procedures can be used for protecting almost any type of tank against deterioration:
1) If necessary dry the walls (consider use of heat guns);
2) Coat unprotected interior surfaces by spraying or brushing structural members with a gas oil with 2% VSI 8235. For floating roof tank all unpainted surfaces exposed to open air shall be protected with Shell Ensis 30 or 158 or Shell Autoseal 1835;
3) Avoid damaging floating roof seals by covering with tarpaulins or equal.
4) Close all manholes with gasketed covers, but breathing not to be obstructed.
5) Leave floating roof drains open. Verify periodically for pluggings and support the roof in high position. Inspect periodically for water ingress.
6) Maintain the tank exterior according to the plant maintenance painting program or maintain the weather seals on insulated tanks. Pay special attention to the seal between tank bottom and foundation to avoid water ingress under the tank bottom.
7) Check cathodic protection periodically.
