Category Archives: vigilance

affordances, design, errors, expertise, rock climbing, safety, vigilance, warnings

Brilliant guard against accidents in indoor rock climbing

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For those who don’t follow news of climbing accidents as closely as I do, there has been a spate of accidents associated with the automatic belay devices (autobelays) installed at climbing gyms.

These devices are handy to have around as they negate the need for a climbing partner, allowing one to exercise and train alone. The climber clips his or her harness into the device at the bottom of the wall, and it automatically retracts (like a seat belt) when you climb upward. At the top, you let go of the wall and the device lowers you slowly back to the ground. You are probably imagining that the accidents had to do with failures of the equipment – while that is not unheard of, the most recent issues have all been with climbers forgetting to clip into the system at all.

The most recent tragedy occurred this past September, where an experienced climber died after a fall in a Texas gym, and it’s been listed as so common it happens at “every gym,” though not always resulting in a fall. Here is the facebook page with members of another gym discussing a similar accident.

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If you talk with climbers or read accident forums you will invariably be faced with a large contingent bent on blaming the victim. I’ll grant that it is hard to imagine forgetting to clip into a safety device and climb 30 feet up a wall, but that’s because I hardly ever do it. One characteristics these accidents share is that the victims were experienced and used the auto-belays frequently.

When a procedure becomes automatic, it becomes more accurate and less effortful, but it also becomes less accessible to the conscious mind. When a step is skipped, but all other steps are unaffected, it’s especially hard to notice the skipped step in an automatic process. If caring more or working harder or “being more careful” could actually prevent this type of problem, we wouldn’t have any toddlers left in hot cars, perfectly good airplanes flown into the ground, or climbers falling because they didn’t clip into the autobelay.

That brings me to the device I saw installed at a climbing gym last night.

guardAbove: The guard in place, clipped to the wall and ready to go. Notice how it blocks the footholds of the climbs.

photo 2Above: Nikki shows how to unclip the guard before attaching to her harness.

 

photo 4Above: Clipped in and safely ready to go. Guard is on the ground and out of the way (it is ok to step on it!)

Let me tell you why I think this is brilliant.

  • It’s highly visible.
  • It functions as a guard. This adheres to the hierarchy of safety: First, try to design out the hazard. Second, guard against the hazard. Last, warn. These are in order of effectiveness. Prior to this device, I had only seen signs on the wall saying “Clip in!” (And a year ago, even those didn’t exist.) This device physically blocks the start of the climbing routes, demanding interaction before one starts climbing.
  • Using it properly does not add any additional time or mess to climbing a route. If it weren’t there, the climber would still have to unclip the autobelay from an anchor close to the ground, etc. With it there, the climber does the same thing and once done, the guard becomes a flat mat that doesn’t get in anyone’s way.

Is it perfect? No. You can also climb with a belayer on the same or nearby routes, and then it’s also blocking your way at the start of the climb. Some adaptation should be made by the route-setters at the gyms to minimize this. But overall, what a great and simple solution.

 

academia, aviation, classroom, safety, vigilance

Collection of Aviation Safety Articles & Student Activity Ideas

I recently came across an impressive collection of Human Factors related safety stories, mostly concerning aviation, from a the System Safety Services group in Canada. The summaries are written in an accessible way, so I recommend this site for good classroom examples. I was already thinking of a classroom activity, perhaps for an undergraduate course:

In class:
Please read the following excerpt (abridged) from Aviation Human Factors Industry News Volume VII. Issue 17. Provide a list of the pros and cons of allowing ATCs to take scheduled naps during their shifts. Put an * by each pro or con that is safety related. The full article is available via the link above.

…the FAA and the controllers union — with assistance from NASA and the Mitre Corp., among others — has come up with 12 recommendations for tackling sleep-inducing fatigue among controllers. Among those recommendations is that the FAA change its policies to give controllers on midnight shifts as much as two hours to sleep plus a half-hour to wake up. That would mark a profound change from current regulations that can make sleeping controllers subject to suspension or dismissal. Yet, at most air traffic facilities, it’s common for two controllers working together at night to engage in unsanctioned sleeping swaps whereby one controller works two jobs while the other controller naps and then they switch off…

More than two decades ago, NASA scientists concluded that airline pilots were more alert and performed better during landings when they were allowed to take turns napping during the cruise phase of flights. The FAA chose to ignore recommendations that U.S. pilots be allowed “controlled napping.” But other countries, using NASA’s research, have adopted such policies for their pilots. Several countries — including France, Germany, Canada and Australia — also permit napping by controllers during breaks in their work shifts, said Peter Gimbrere, who heads the controllers association’s fatigue mitigation effort. Germany even provides controllers sleep rooms with cots, he said. …fatigue affects human behavior much like alcohol, slowing reaction times and eroding judgment. People suffering from fatigue sometimes focus on a single task while ignoring other, more urgent needs.

One of the working group’s findings was that the level of fatigue created by several of the shift schedules worked by 70 percent of the FAA’s 15,700 controllers can have an impact on behavior equivalent to a blood-alcohol level of .04, Gimbrere said. That’s half the legal driving limit of .08. “There is a lot of acute fatigue in the controller work force,” he said. Controllers are often scheduled for a week of midnight shifts followed by a week of morning shifts and then a week swing shifts, a pattern that sleep scientists say interrupts the body’s natural sleep cycles.

At home:
Your homework assignment is to identify another work domain with similar characteristics where you believe fatigue is a safety concern. Write an argument for requiring rest during work hours or other solutions for fatigue. Again, specifically call out the pros and cons of your solution.

A list of all articles, in newsletter form, can be found here.

Photo credit mrmuskrat @ Flickr

aging, alarms, automation, aviation, errors, multi-tasking, vigilance

Pilots forget to lower landing gear after cell phone distraction

This is back from May, but it’s worth noting. A news story chock-full of the little events that can add up to disaster!

From the article:

Confused Jetstar pilots forgot to lower the wheels and had to abort a landing in Singapore just 150 metres above the ground, after the captain became distracted by his mobile phone, an investigation has found.

Major points:

  • Pilot forgets to turn off cell phone and receives distracting messages prior to landing.
  • Co-pilot is fatigued.
  •  They do not communicate with each other before taking action.
  •  Another distracting error occurred involving the flap settings on the wings.
  • They do not use the landing checklist.

I was most surprised by that last point – I didn’t know that was optional! Any pilots out there want to weigh in on how frequently checklists are skipped entirely?

 

 

Photo credit slasher-fun @ Flickr

errors, health/healthcare, safety, vigilance

Fun with confusing medication names!

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Check out this post from The Consumerist about how unhappy the FDA is with Durezol and Durasal.

A hint: It’s ok if you accidentally use Durezol when you wanted Durasal, but the penalty is high for using Durasal instead of Durezol!*

This link contains an explanation of the names:

When drugs are submitted to the FDA for approval, the Agency carefully screens their proprietary names for similarities. However, Durasal (salicylic acid) is an OTC medication that did not undergo the approval process. That is why the two names exist side-by-side in the pharmacies.

Thus far, the FDA is asking pharmacists to “be vigilant.” I think we know how that usually plays out.

 

*Durezol is eye drops. Durasal is wart remover.

alarms, errors, signs, transportation, vigilance, warnings

11 feet 8 inches

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A train trestle in Durham, NC has a clearance of 11’8″.

The typical height of a large rental truck ranges from 11’6″ (don’t bounce!) to 13’6″.

How often do you think about clearance when driving? Do you think you could adjust to thinking about it 100% of the time in your rental truck?

I’ve seen parking garages that have a hanging bar well before the low ceiling to notify drivers that they are not going to make it. The bar, on chains, will bang the front of the truck but not peel the top off as the bridge does. The trucks in this video are going to quickly, this warning would have to come well before they crossed the intersection. This solution probably has problems too. I’m sure there would be drivers who were planning to turn before the bridge that get mad that a bar hit their truck. Also, getting someone to pay for and maintain the bar might be difficult as the trestle owners want to blame the drivers (and so do other drivers, if you read the comments on the video.)

More video and information is availible at 11foot8.com. Videos copyright Jürgen Henn – 11foot8.com.

APA, aviation, cognition/memory, Division 21, errors, vigilance

Blogging APA Division 21: You’re Looking Harmless Today

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I‘m on a plane writing this post and I look harmless, or at least not threatening.

According to work presented by Poornima Madhavan from Old Dominion University, being a female in the screening line means I am less likely to be hassled by a false alarm of a screener seeing a threat in my bag.*

In work done with her graduate student Jeremy Brown, Dr. Madhavan found that participants in their studies consistently reported more false alarms (detecting a threat that was not there) when the passenger was male. Both genders showed this bias.

Because this bias affects a perceptual task (detecting a knife in a baggage x-ray) it is called a “Social Cognitive Bias.”

This project is a wonderful example of an applied experiment that gives us information on the effects social and cultural structures can have on cognitive ability.

Photo credit Wayan Vota under a Creative Commons license.

*No matter what gender you are, carrying climbing gear guarantees a search!

aviation, cognition/memory, errors, safety, vigilance

Visual Search and Airport Security Screening

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Funny I should have mentioned conjunction search the other day, since this post is all about new research by Jeremy Wolfe who has and continues to contribute to the visual search literature.

In this new work, already mentioned on i09, Wolfe and his former research assistant Michael van Wert investigated complex visual search as it applies to baggage scanning at airport security. When the target being searched for (i.e., weapons) does not appear frequently, detection rates go way down. Even if it is detected, people have a hard time inhibiting the motor response of saying “no, I didn’t see anything.”¹

Of course, human difficulties in searching for rare events is nothing new. The big contribution of this work was to determine that we go through two decision criteria when searching and each affects our response time and our accuracy.

¹I’m liberally translating; these aren’t the specifics of the study method.

The primary sources mentioned in this post can be found:

Wolfe, J. M, & van Wert, M. J. (2010). Varying target prevalence reveals two dissociable decision criteria in visual search, Current Biology, 20(2), 121-124

Another good article with implications for the TSA:

Warm, J. S., Parasuraman, R., & Matthews, G. (2008). Vigilance Requires Hard Mental Work and Is Stressful. Human Factors, 50, 433-441.