Incident Report

Subject:               FW: Storage Tank Collapse - The Power of a "Plastic Bag"         

Date of Email reporting Incident:   FW: Storage Tank Collapse - The Power of a "Plastic Bag"

Report Detail:

Attached are three photos, courtesy of the API showing a tank Collapse   as a result of drawing out of a tank when the vent valve was covered by a plastic bag to "protect" it during tank painting.  This is the third such tank collapse that I am aware of from the exact same cause.  Who knows how many more times this happened that I am not aware of.  The third photo best shows the full extent of damage.  The other two are close ups of the bottom lifting off the foundation during the collapse and the top of the collapsed tank where the vent is covered with some plastic. The scaffolding around the tank is for painting.

Lesson Learned:

1. Covering the vent valve during tank painting is fairly standard practice; unfortunately leaving it covered when drawing out of the tank is very non-standard practice.
2. This is an expensive, embarrassing mistake that is entirely preventable by adherence to good procedures and good communications  between operations and maintenance.
3. This sort of thing nearly always results in total destruction of the tank.  It is generally not cost effective to repair tanks with this  extent of damage.
   For some, it is hard to believe that the plastic over the vent valve is stronger than the steel tank under the vacuum conditions that
   are created when drawing product out of the tank.  Seeing is believing.

Please make sure that all the right folks at your site and in your organization see what damage can be caused by such mistakes, and thereby have the opportunity to avoid these expensive mistakes, by learning from the misfortune of others.