Victor Singer
VSinger01@aol.com
AN EXAMPLE OF WHAT LIVING IN A POST 9/11 ERA MEANS:
Somebody with a rifle shoots at a street light
The bullet goes thru the globe and the bulb shatters
The globe has two holes in it
Then he shoots at an aboveground storage tank
Would you prefer shattering or leaking ?
Do you have the option to choose?
Technology is available to control fracture mode at detail design / material selection stage.
- Fracture Mechanics, “new” since WW II
- Technology suitable for tanks ~ 25 years old
- Engineers now practicing, writing regulations not exposed to it in college (except in aerospace curriculum) tend to avoid new technology even when aware
The Jeffrey Davis Aboveground Tank Act applies to tanks above 12500 gallon volume
- If contents environmentally hazardous (or worse)
- 520 such tanks in Delaware
- 134 > 1 million gallons
A regulation is being written (under DNREC)
- Subcommittee on new installations section
- Draft depends on reference standards for details
- Fracture mode control provisions in reference standards are weak, ineffective for large tanks
Effective fracture mode control provisions
- Prepared and submitted to subcommittee based on only a re-interpretation of data from material tests of a type already required and learning to use square root button on pocket calculator applicable only to new metal tanks
Subcommittee prefers avoiding brittle fracture
- During latest meeting, deleted the only 14 words that addressed the issue
- Deleted: “the ast’s resistance to brittle fracture under the harshest of conditions must be shown.”
I ask you to demand either of the following:
- A firm requirement of leak-before-burst capability for new metal aboveground storage tanks subject to the act. Or
- An explanation as to why learning to use that square root button is too much to require.