In the world of bulk liquid and dry bulk it has been my experience that if hoses were hooked up the blue flat were in place before and after.
Montford L. Switzer
Switzer Tank Lines, Inc.
Fall Creek Leasing, LLC.
From: main@RealSTMFC.groups.io <main@RealSTMFC.groups.io>
On Behalf Of Bob Chaparro via groups.io
On another group a person commented about this photo:
"Does the blue flag rule cover cars being loaded or unloaded? No.
Are/were blue flags used to protect cars being loaded or unloaded? Yes."