Wooden sleepers in particular, especially if they have a thin film of dew on them.
When I started working for BR Southern, I was given a number of safety leaflets. They included one about not walking on the sleepers, one about not stepping on the rails, and one about not stepping on the ballast (as the stones can move under your foot). So where was I supposed to walk? No leaflet about not walking on the live rail!
Yeah, I was told similar, don't walk on the rails, sleepers or ballast, and don't walk on the troughing. I so wanted to say, what, am I suppose to (insert appropriate coloured language) fly then...!
In the good old days of BR, along some lines, there were the remains of the cess path. This was a fine gravel rather than ballast sized stones (the old guys told me they were once so good you could ride the company supplied bicycles on them). And by far, was the best and easiest place to walk. The trouble was, it was rare for the railway to maintain them apart from along published walking routes (mostly along or near depots). They often got covered in spent ballast, earth from the sides of the cutting or old/new sleepers, rails and other items were left on them. Or some contractor would lay a new SCT route on top of the path because that was easier than digging a trench to put the SCT in (the lids of the SCT are or were supposed to be level with the surface of a path).
If the line was re-laid (or ballast "cleaned") using modern ballast machines that normally meant the path was toast.
Side note: during some works these days, there is a requirement to provide a cess path, so in some places they are making a comeback.
Where there was no cess path or it was overgrown, in practice, if the troughing route (officially surface concrete troughing - SCT) if actually concrete, in good condition and free of overgrowth was my preferred place to walk.
If having to walk along the four foot, and the sleepers were concrete with the tops clear of ballast and they were not slippery with moss or whatever, that's where I walked.
Otherwise I used to walk along on the ballast. If in the four foot trying to make sure I stepped on the ballast between sleepers and not on the ballast that was on top of sleepers. As loose ballast was just as deadly as a slippery sleeper.
The concrete cable conduit ?
Officially called SCT where I worked - see above.
High ballast shoulders were always my concern, particularly where you have a live rail at the top. Getting down in a hurry at least you can jump over the live rail and down into the cess. But climbing up a high ballast shoulder with a live rail at the top could be interesting.
Loose ballast lying on top of a sleeper can also lead to your foot slipping.
Old wooden sleepers with creosote or tar preservative often can have patches of the tar on them. While not dangerous, if the tar gets in the soles of your shoes, you could make yourself quite unpopular if you trod it in somewhere.
We used to get ear ache from the cleaner when we trampled dirt, oil or grease in...
As well as wooden sleepers being slippery or having excessive tar on them, the other problem was that as they rotted, many did so from the inside leaving them normal looking normal. Until you stepped on them, then the now very thin bit of good wood on the top would give way dropping your foot into the rotten core and maybe tripping you up in process... For some reason, these sleepers rotted more in the middle than the area under the chairs.
Breaking of the lid is possible but it would probably be visibly damaged. I was thinking more of the risk of it becoming dislodged and dropping into the trough. I do remember being warned about that on a PTS course (30+ years since I did one but I doubt that has got any better).
BR tried various designs and types of troughing. By far the worst for walking on was the grey plastic type. That was extremely slippery when wet or worse, when it was icey. More than once I've taken a tumble. And over the years, the plastic became brittle, so the lid would give way under your weight.
The concrete type, the short length (half a metre in length I think) design doesn't have metal reinforced steel rods. So if either the lid or the U-shaped base cracks...
The longer type (all one metre in length) does have metal reinforcing. So broken bases (U -shaped) is less common. However, the edges of the lids don't have metal reinforcing. So a part of the edge of a lid can either already be damaged or missing, but with the lid looking normal until you step in it, you don't know... Or very occasionally it can break when you step in it.
Trough lids can also, as well as the mentioned risk if them moving, be just as slippery as sleepers for the same reasons
Oh yes, especially if they spend a lot of time in the shade, like in cuttings.
Trough lids can move when stepped on and there is the potential risk of cracking them if regularly stepped on.
Normal walking on them if the better concrete type does not cause damage. Most of the damage is done when the lids are not fitted correctly. Especially if whoever is doing it just drops them down instead of carefully lowering them. Or when they are tight, using brute force.
So that's what we were missing, we were all wearing Crocs so it's no wonder we were slipping and sliding all over. Safety boots are the answer, got it!
The railway supplied safety boots have varied in quality over the years, some bad good grip, others had very little...
And 30 years later some of those lids are now very brittle, we always taught to avoid walking on them. Obviously a lot of it is being renewed with polymer replacements that have a textured lid but in my experience they were still lethal in the winter.
The modern polymer type can cause you to build up a static electricity charge, which you get to know about when you then touch an earthed metal object (such as a metal fence)!
The same applies to walking in the fourfoot if stepping from one section of ballast to the next. If I recall correctly it's too short for a normal step but trying to step over two sleepers would be too far. This is one reason why the cess is safer, but only if a clear cess exists.
There have been various sleeper spacings used. Some of the older standards happen to be close to my natural stride. But the modern sleeper spacing for main lines are too close together for me. So I have to "quick step"...
Do safety boots give better grip than walking shoes or boots?
When I was told to walk down the line that was the only instruction I got! It was about 40 years ago.
Not always - see above. Also note that the safety boots required have to have a steel plate in the sole to protect your foot against shape things like nails... So the boot is less flexible.