Better Roads Staff
Down I go on rappel, looking carefully at the steel around me, foot by foot, every few feet moving my backup device down with me to keep it within arm’s reach. I stop at areas I need to document and photograph. Eventually, 80 feet down, I reach the bottom of this vertical and stand up on the lower chord. Nothing exists below me now but lots of air and the river 300 feet below. As I begin to switch my rope access set up from descent to ascent and prepare to jumar back up the rop I just came down, I think to myself: one done and many more to go over the course of the next week…let’s hope the rest of this inspection goes as smoothly as this first rappel.
Ryan Nataluk, P.E., is a bridge inspection program manager for Stantec. Nataluk is SPRAT level 2 rope access technician.
Not all bridges are created equal
Prior to about 2000, standards did not exist for inspectors accessing a bridge via rope access, points out Ryan Nataluk, P.E., bridge inspection program manager for Stantec. The first time bridges were climbed [for inspection] using ropes , a.k.a. rope access,
Should be as such: …using ropes, a.k.a. rope access, was in the mid-1980s, Nataluk says. was in the mid-1980s, Nataluk says. The process gained more popularity in the 1990s, and since about 2000, it has been in a growth mode. “Prior to 2000, there weren’t really any standards,” he says. “The No. 1 thing in safety is anchors and a double rope system.”
Now with SPRAT, which works with the American National Standards Institute (ANSI) and the Occupational Safety and Health Administration (OSHA), climbing methods and safety practices can be regulated. There are three levels of SPRAT certification. Above level 3 is considered an “evaluator.” Within a rope access team, a level 2 or level 3 candidate undergoes extensive self-rescue training in case of an accident. You go through a lot of rope rescue training, Nataluk points out. “It’s similar to mountaineering type rescue training.”
A minimum of two inspectors must climb together, but a typical rope access inspection team has four to six people training, with a team of four being the most common. “You cannot climb alone,” Nataluk says. “You always work in at least pairs of two.” A typical partnership is a level 2 supervisor and a level 1 inspector that breaks into teams, says Nataluk, who has a SPRAT 2 certification.
Caltrans’ Sahs (also a SPRAT level 2 Technician) adds: “Comprehensive climb training is essential for the safety of personnel as well as for the appropriate selection of techniques and equipment for a particular task.” The complete Caltrans bridge Rope Access training consists of two courses: a comprehensive 32-hour basic course conducted by a qualified instructor and a six-hour practical test and a 32-hour self-belay course followed by a 6 hour test. The curriculum – which is broken down into classroom covering knots, equipment, elementary climbing, rope and mountaineering techniques and safety and rescue and hours of practice applying the techniques on a steel truss bridge followed by the timed practical test.
Climbing, however, is not an efficient method to inspect every bridge. “Some bridges will require traditional methods,” Nataluk says. More so than not, using an under bridge inspection unit – commonly known as a “snooper” on a redundant concrete I-bream structure is more cost efficient. “Where climbing comes in is on steel trusses and arches,” he says.
Nataluk gives examples of steel structures built about 50 to 60 years ago over the Mississippi and Ohio rivers. “They have a lot of lacing and bracing to tie off to so they are much easier to climb,” he says.
Climbing on a traditional concrete arch bridge such as those over an interstate can be challenging because myriad anchorage points are needed so the climbing inspector can ensure the rope can be tied off. “On a lot of traditional concrete bridges, there aren’t many tie off point, and most owners don’t want you drilling into their structures,” Nataluk points out. “On steel structures, there are a lot of places where you can tie off your anchors. This facilitates better climbing.”
During a traditional bridge inspection, traffic control needs to be set up. However, traffic control is not needed in rope access inspection – unless the distance below the structure isn’t great enough. “You might have to block off a lane, but that is rare,” Nataluk says. “When climbing a bridge [to inspect it], you don’t have to use mechanical equipment so you don’t have to use traffic control.”
This, in turn, eliminates the time constraints associated with traffic control. Traditional inspections that require lanes to be blocked off typically have to begin after the morning rush hour and end at 3 p.m. before the afternoon rush hour or must resort to night inspection. “Rope access provides more room to move around the structure,” Sahs says. “In photographs it might look daring or dangerous, but it’s actually safer for the inspector to not be in a traffic control zone.”