Judging by the amazing story of how 22 people survived the deadly May 20 tornado by taking shelter in the vault of the $3 billion Tinker FCU's Moore, Okla., branch, they take tornado safety seriously in the Sooner State, too.

Of course they took shelter in the vault. Anybody would.

Or would they?

Credit union disaster plans usually include detailed information on how to provide continued service to members and handle service interruptions. But do they instruct employees what to do in the event of every emergency? Does your credit union drill for those emergencies?

I spoke with Phil Tschudy at CUNA Mutual about tornado procedures and whether the vault is a common, or even a good, place to take shelter. It turns out the employees at TFCU were lucky: he said vaults aren't often an option for branch employees, because many branches don't have safe deposit boxes, and therefore only have safes, not vaults.

But more important than a vault is a written plan, Tschudy said.

Whether your credit union is located in Tornado Alley or on the San Andreas Fault, employees should not only know what procedures to follow in the event of a natural disaster, they should be trained and drilled on it, too.

I spoke with a couple of credit union managers in Kansas, and they said they have written tornado procedures for each branch, because some locations have basements while others do not. In some cases, the procedure calls for employees to leave the credit union as soon as tornado sirens sound and seek shelter nearby.

Tschudy also said that sheltering members, or even employees from the business next door, doesn't present a situation where a credit union would take on additional liability, provided everyone follows a well-written plan. However, if there was not a plan, or employees didn't follow it, the credit union could be liable because a victim could argue in court that the institution was negligent.

Many credit unions located in what has traditionally been dubbed Tornado Alley – which includes parts of Texas, Oklahoma, Colorado, Kansas, Nebraska and Iowa – probably already have a tornado procedure in place. However, deadly tornadoes have recently struck locations outside those states, such as the devastating May 2011 Joplin, Mo., tornado that killed 158 people and the March 2012 tornado in West Liberty, Ky., that killed six.

According to the National Oceanic and Atmospheric Administration, strong E3, E4 and E5 tornadoes primarily hit states in the Great Plains, South and Midwest. However, these potentially deadly tornadoes have also struck in unlikely locations like Flagstaff, Ariz., Albany, N.Y., and Miami.

That means most credit unions probably aren't prepared with a written plan or procedure for employees.

Nobody wants one more to-do item on their compliance list. So if you need some motivation, just take a look at what is left of Tinker's Moore branch.

Of course you'll write that procedure.

Who wouldn't?