By Bill Adams

Did you ever end up in a discussion where you can’t remember what the original topic was, who started the conversation, and why it lasted for three days? Welcome to the world of morning coffee with some of the Raisin Squad. One of the geezers brought in a photo of an aerial ladder failure that obviously happened years ago. The firefighters in the picture were wearing ¾-length boots, rubber coats, and tin helmets—appropriate rubber goods for the 1970s. It appeared the extended ladder just dropped out of the sky. The gang started in on why ladders fail, who’s at fault, what broke, why do some manufacturers build crap, and how come you never hear about snorkels (elevating platforms) failing.

When one white hair mentioned driver (operator) error should always be considered, the rest unloaded on him for picking on the drivers, especially if grievous injuries occurred. The squad protects “its own” despite the fact that the last time they rode a rig it was legal to ride the back step. They’ll blame lack of training, the manufacturer, mechanical error, lack of maintenance, and newfangled electronic controls and gizmos but never the firefighter. The general consensus was if God or the devil didn’t cause a failure, it was because of little or no maintenance. 

Considering it was safe to elaborate on the topic and attempting to impress them, I brought in a couple of pages copied from National Fire Protection Association (NFPA) 1911, Standard for the Inspection, Maintenance, Testing, and Retirement of In-Service Emergency Vehicles. My contention was the cylinders holding the aerial in the sky could have failed. I explained that sentence 22.8.6.28 says: “The extension cylinder shall be subjected to a drift test as follows:

(1) With the hydraulic fluid at ambient temperature, place the aerial device at 60 degrees elevation at full extension.

(2) Mark the cylinder position or the second aerial ladder section in relation to the base section.

(3) Allow the ladder to stand for 1 hour with the engine off.

(4) Measure the drift and verify that the results do not exceed the manufacturer’s specifications for allowable cylinder drift.”

I said that NFPA 1911 defines drift as “A time-dependent movement away from an established position.” And, it says “…these measurements shall be recorded in the test record so that a year-to-year comparison can be made.” Then, to really impress them, I said that’s so you can tell from year to year if the stick might droop down on its own. They beat that up for a while. “I’ve never heard of an aerial drooping or drifting.” “You’re making that up.” “This has to be something new they just came up with.” One semi-smart geezer said, “Hey—that says the manufacturer allows them to drift down. How much is an allowable drift?” I don’t know. “You should.” He’s right in asking how much should an aerial ladder drop (or drift down) on its own. How many people really know? One Raisin said that if an aerial is above a building’s parapet and it drifts down, it could damage a prepiped waterway. Another said, “Water’s not usually piped to the last fly, and anyhow the ladder shouldn’t be extended that far from the roof’s edge.” I said that doesn’t make it right. “It does in my mind.”

Photo 1<