How safe is a chest harness when used without a sit harness?

Question

How safe is it to use a chest harness without a sit harness? I ask this question because of an experience I had while on holiday.

A couple of years ago I was in China and hiked/climbed HuaShan (see this link for some info/pictures). This is basically a hike but with some very steep sections protected by chains. The most dangerous (but optional) sections are cordoned off and, to access them, you are provided with what seemed like a chest harness by staff - I found a photo of one here. Would a harness of this kind be effective in the event of a slip/fall? I'm not sure; naively I'd have thought that a fall could leave you in an awkward position from which self-rescue would be impossible, or you could even slip out of the harness??

EDIT: thanks for the responses. Some more info about the specific situation at Hua Shan...

1. Until a few years ago there was no safety equipment whatsoever, despite the fact that this is an extremely busy route with access seemingly regulated by the authorities. I guess that China is not well known for its high standards of health and safety.

2. The harness photo doesn't tell the whole story; there are also some very steep (almost vertical) sections - the first link contains some photos which hint at these sections.

3. It's not 'real' climbing - it is, however, a spectacular example of a situation where the use of wooden planks and pieces of iron has allowed access to terrain which would otherwise be considered a very highly graded and exposed rock climb.

4. Some people would probably be happy to follow this route without any protection. However, I think that many people would prefer to have some level of protection on the route. I'm just concerned that the protection provided may offer only a false sense of security.

Answer 1

TLDR:
Never ever use a chest harness alone.

It depends on what you mean by effective: It can stop a fall, there was a time (before the seventies) when chest harnesses (alone) were used in mountaineering. The big problem comes after: suspension trauma.

This is not limited to breast harnesses at all. This is the main life-threatening problem apart from direct mechanical injuries after a fall in climbing. Without movement the blood will get stuck in the lower extremities leading to orthostatic shock, leading to a circulatory collapse. According to Pit Schubert[1]:

after only 2min hanging in a chest harness the arms are paralysed.

This means you cannot rescue yourself anymore. According to Schubert hanging freely (in any kind of harness) is deadly after a maximum of 2h, potentially much earlier.

So assuming on this trail you may be alone a chest harness can prove fatal in case of fall. Even if somebody arrives in time to save you (i.e. bring you into lying position before you are in shock) you will likely sustain damage to your arms/chest.
In addition an operator using chest harnesses does not show off competence. You have to wonder whether safety is precarious in other regards as well. I would immediately stop using their services.

[1] Pit Schubert, Sicherheit und Risiko in Fels und Eis (Band III), pp. 45.

Answer 2

In this sort of situation a chest harness is reasonable because its main purpose is to keep you attached to the route via a short sling as protection against slips as opposed to actual climbing where long, high energy falls might be expected. So it should not be loaded with much more than you body weight and it it more about stopping a fall than arresting one.

Also for a harness issued to the general public a chest harness is likely to fit better, be more comfortable and be harder to fall out of than a sit harness, which generally needs to be well flitted and adjusted to work and may fail if you fall inverted (more likely for an inexperienced climber on a 'walking' but exposed route).

Also in this situation you are less likely to be actually injured by falling and you aren't going to fall far there is a good chance that you could self rescue by pulling yourself back onto the ledge.

Note that this is an entirely different situation from climbing on a long rope while belayed.

Answer 3

This is basically a hike but with some very steep sections protected by chains.

If I'm interpreting the photo correctly, this is a sort of horizontal via ferrata, and the protection is the steel cables, not the chains.

This does not seem like a setup that would have been designed by anyone whose background was in mountaineering. A more normal setup based on standard mountaineering practices would use a seat harness, and in addition the would be some provision for allowing the climbers to pass the bolts while staying protected. As far as I can tell from the photo, the guy in the red shirt is going to have to unclip his (non-locking?) carabiner, then clip it onto the next section of cable. While it's unclipped, he has no protection.

But I don't know if any of this matters, because they're walking on horizontal wooden boardwalks, and they have the cables or chains to hold onto with their hands. I wouldn't really feel any need for a belay in this situation, so it might not matter much if the protection is not reliable or mainly psychological.

How safe is a chest harness when used without a sit harness?

This is really a whole separate issue that doesn't apply to the situation being described, where the belay is unnecessary. For real climbing, you use a seat harness because you need more than a psychological belay.