What constitutes mountain exposure when hiking or scrambling?

Question

In this question, I focus on the fall exposure component. While I understand the perception of danger will vary from person to person, I'm having trouble characterizing mountain exposure. I can see where when you reach YDS (Yosemite Decimal System) 3rd class, it's evident that overall steepness usually makes the path exposed in some way, but at 1st and 2nd class ratings, how do we define exposure? I'll be asking a few questions here but they all aim to aggregate the attributes of a hike or scramble that would make it exposed.

• Is the mere presence of a drop-off on one side enough to consider that particular section exposed even if walking on mostly level ground?

• Does the footing have any impact, like loose scree on a long steep talus (let's say over 35°)?

• How long or steep does a slope have to be to become exposed? I have Greg Slayden's Mt. Columbia trip report in mind where he mentions the constant steepness being overwhelming.

• Is a narrow path traversing a slope that ends further below at a drop-off considered exposed?

This question is inspired by my recent experience with Alan Kane's Scrambles in the Canadian Rockies guide. It seemed to me that what constituted exposure was strangely defined or that I didn't understand the concept. For example, I found the slabby ridge up the classic Mt. Rundle quite exposed at its narrowest point (and that's at the most a 2nd class hike), but didn't find the 3rd class moves up Mt. Temple to be that dramatically exposed.

Answer 1

"Mountain Exposure" is a very broad term. Simply defined, it means you are exposing yourself to some risk of injury or death in the outdoors.

Your level exposure while climbing is determined by how unprotected your climb is, which is summed up by how likely you are to sustain injury if you took a fall. On vertical climbs, the availability of anchors or placements for trad gear, and the availability of good holds constitutes protection; the lack thereof determines exposure. On hikes, the steepness of the slope, and ground cover determine exposure. You're much less likely to go tumbling to the bottom of a slide covered in thick willows than you are on a barren talus slope. The willows can stop and even cushion your fall, whereas you can cartwheel all the way to the bottom of a steep talus slope.

The term is not exclusive to falling. Mountain exposure encompasses exposing yourself to the elements as well. Wind, weather, temperature, the sun; there are many levels of exposure.

When hiking or climbing in good weather however, your level of risk of sustaining a serious injury or dying in the event of a fall is what constitutes your level of exposure.

Answer 2

Exposure is more a feeling that there is nothing below you in the event of a fall rather than a steepness.

A trail that was level as it winds its way around a mountain but has a 1500 ft drop off on one side would be considered exposed, while Class 3 moves up a slope might not be depending on the person.

Here is a picture of the narrows on the Long's peak trail,

Source

Notice how the trail is mostly level, and yet there is a dropoff right there.

Or see this one of the trail to Angel's landing with a railing,

Source

It doesn't depend on the footing or the length of the trail because you can have good footing or a very short section of exposure. There are rock climbs where you go from no exposure to what looks like an infinite amount of blue sky below in the space of a couple moves.