Hi vis discussion thread (read post #1)

CramCycle · 27-07-2018 09:43AM

tomasrojo wrote: »

Interesting bit of work: testing how well people in a driving simulator see cyclists wearing yellow jackets and just wearing grey.

Basically, people could see hi-viz cyclists further away, but only in scenarios where they didn't have much trouble seeing the grey-wearing cyclists (I think)
https://www.sciencedirect.com/science/article/pii/S0925753518309871?platform=hootsuite

One glaring flaw with the paper is the assumptions at the beginning:

In several cases involving collisions between cars and cyclists, car drivers failed to detect the latter in time to avoid collision because of their low visibility or sensory conspicuity. We studied the effect of a yellow cyclist jacket on the detection of cyclists by motorists in an urban environment during daylight hours.

I have seen another paper showing that when there is various light heights used against oncoming traffic, a hi vis has a slight improvement on visibility distance. Not sure if it was enough to warrant usage as I cannot recall and the scenario where it was useful was when cars had their full beams on (against each other). Interestingly (and again from memory) while full beams were annoying, when asked to mention the distance they seen something at, it had very little affect.

tomasrojo · 27-07-2018 10:20AM

CramCycle wrote: »

One glaring flaw with the paper is the assumptions at the beginning:

In several cases involving collisions between cars and cyclists, car drivers failed to detect the latter in time to avoid collision because of their low visibility or sensory conspicuity. We studied the effect of a yellow cyclist jacket on the detection of cyclists by motorists in an urban environment during daylight hours.

I have seen another paper showing that when there is various light heights used against oncoming traffic, a hi vis has a slight improvement on visibility distance. Not sure if it was enough to warrant usage as I cannot recall and the scenario where it was useful was when cars had their full beams on (against each other). Interestingly (and again from memory) while full beams were annoying, when asked to mention the distance they seen something at, it had very little affect.

Yeah, I think they just took the conventional road-safety wisdom about collisions occurring because drivers "just couldn't see" the cyclist or pedestrian (without considering the Mandy Rice-Davies counterview: Well, they would say that, wouldn't they).Also "in several cases" is more than a little vague.

However, I don't think "cyclists are so hard to see" is a working assumption baked into the study design. It seems to be about how much sooner you can see hi-viz cyclists, and in what context, so any bias on the part of the researchers shouldn't really matter, provided the respondents aren't given leading questions.

Interestingly, on the second paper, I've heard it said (might have been in Cyclecraft that wearing reflective clothing probably increases the chance of drivers keeping the lights on high beam on rural roads, maybe because they like the reflective effect, or feel it's the right thing to do, making the cyclist "more conspicuous", even though they've already seen them. Dazzling the cyclist is an obvious problem, but even following the cyclist, delays in dipping the lights could dazzle oncoming drivers.

I guess the second study would be more relevant for rural roads, as high-beam is not that common in the urban environment, which the first study is about.

average_runner · 27-07-2018 11:57AM

realitykeeper wrote: »

I will vote against any political party that tries to force me to wear a high vis vest or a helmet. They can encourage common sense and do an awareness campaign by all means but such a law would be an imposition on cyclists. Cycling needs to be encouraged, not have impositions placed upon it. If there were no motorists, there would hardly be any need for high visibility so motorists are the problem. This country needs to reduce its carbon emissions so encouraging motorists to cycle would be a better idea.

The electric cars will reduce the emissions problem but it will also bring a different problem, their noise output will be alot lower so more care will be needed!!

AndrewJRenko · 27-07-2018 12:13PM

average_runner wrote: »

The electric cars will reduce the emissions problem but it will also bring a different problem, their noise output will be alot lower so more care will be needed!!

It may help the emissions problem, but it certainly doesn't solve it if all the EVs are being powered by oil/coal/turf generated power stations.

average_runner · 27-07-2018 12:19PM

AndrewJRenko wrote: »

It may help the emissions problem, but it certainly doesn't solve it if all the EVs are being powered by oil/coal/turf generated power stations.

Nope it won't but then we again we aren't going to solve such a big issue easily when certain powers (Countries) control it and it drives the world economy.

While the tv show Occupied is based on a fiction, you could easily see it happening

Fitness is something that needs promotion more and more these days, facilities need to match, making things easier for people to do it!

Seweryn · 27-07-2018 12:21PM

AndrewJRenko wrote: »

It may help the emissions problem, but it certainly doesn't solve it if all the EVs are being powered by oil/coal/turf generated power stations.

No, EV cars do not help reducing emissions. The emissions come from manufacturing, mining, end of life recycling (and generating electricity required to power the vehicles)...

07Lapierre · 27-07-2018 12:25PM

Seweryn wrote: »

No, EV cars do not help reducing emissions. The emissions come from manufacturing, mining, end of life recycling (and generating electricity required to power the vehicles)...

Clarkson is right...the most eco friendly car on the planet is a 20+ year old land rover defender! .. Why? because they don't make them anymore and most of the ones still on the road are still one owners who never drove anything else!

tomasrojo · 27-07-2018 01:00PM

Electric vehicles do have lower emissions of NOx, and if you look at just their immediate environment, this is a big advantage. So in cities, where NOx levels are often high enough to be a health risk, they make sense, if they're replacing vehicles that use fossil fuels and can't be replaced by active travel or public transport. Public transport should also switch to electric where possible.

If you can substantially decarbonise electricity supply, and that does appear to be on its way in a few countries, electric vehicles would lead to lower CO2 emissions as well.

EVs still take up an insane amount of room, kill people by colliding with them, make people fat, stop children from playing outdoors, and give off plenty of particulate matter from braking and tyre wear that adversely affects health, so the best thing to do is still discourage the use of private motor vehicles, regardless of whether they're electric, especially in cities.

average_runner · 27-07-2018 01:00PM

Seweryn wrote: »

No, EV cars do not help reducing emissions. The emissions come from manufacturing, mining, end of life recycling (and generating electricity required to power the vehicles)...

You can say the same for the bike frames, tyres, puncture repair kids, the gear people wear, it all adds to the emissions.

The same for the heating in our offices and buildings etc.

We should walk around naked instead with no shoes:D

tomasrojo · 27-07-2018 01:01PM

(This isn't the Electric Vehicle thread, I probably should add!)

tomasrojo · 27-07-2018 01:02PM

average_runner wrote: »

You can say the same for the bike frames, tyres, puncture repair kids, the gear people wear, it all adds to the emissions.

The same for the heating in our offices and buildings etc.

We should walk around naked instead with no shoes:D

No, they were washing bikes.

http://irishcycle.com/2018/06/13/dublin-bicycle-shop-hit-with-e150-fine-after-children-stuck-up-poster-advertising-bike-wash/

Seweryn · 27-07-2018 01:24PM

average_runner wrote: »

You can say the same for the bike frames, tyres, puncture repair kids, the gear people wear, it all adds to the emissions.

The same for the heating in our offices and buildings etc.

We should walk around naked instead with no shoes:D

No, the core of the problem (the elephant...) is very obvious, but very few people are able to see it.

And we are derailing from the subject a little

.

Grassey · 27-07-2018 01:26PM

average_runner wrote:

We should walk around naked instead with no shoes

But not until the excess fat has been burned off please.

magicbastarder · 27-07-2018 01:28PM

Seweryn wrote: »

No, EV cars do not help reducing emissions. The emissions come from manufacturing, mining, end of life recycling (and generating electricity required to power the vehicles)...

to quote ben goldacre, 'it's complicated'.
obviously petrol/diesel is a lot easier to calculate the figures on as they're a more standard fuel than electricity - driving a petrol car here, and driving one in norway will result in similar tailpipe and lifespan CO2.
but comparing EVs in ireland and norway is completely different because the vast majority of their electricity is hydro, and the majority of ours is from fossil fuels.

then you have the complicating factor of the mining and manufacture, and add into that, that with cars, it's usually easiest to distil the emissions issue to CO2, whereas an EV will have much lower particulate/NOX/etc. emissions, which are the ones which play more into the effects of cars on urban air quality.
and you still have tyre dust from EVs (possibly brake dust, i guess, if they're using traditional brakes).

some interesting reading here, you can see the different numbers the different car types and different energy sources produce:
https://www.theguardian.com/football/ng-interactive/2017/dec/25/how-green-are-electric-cars

magicbastarder · 27-07-2018 01:37PM

anyway, getting back to the topic at hand:

tomasrojo wrote: »

Interesting bit of work: testing how well people in a driving simulator see cyclists wearing yellow jackets and just wearing grey.

i wonder/worry how much the fact that the 'drivers' knew they were being tested would skew the results - even if they might not have known they were specifically being tested on the cyclist visibility issue.

someone in a driving simulator, *knowing* they are being watched, will be a hell of a lot more observant than a tired office worker/baker/artificial inseminator/what have you, driving home after a days work, on roads they are (i.e. would claim to be) able to drive blindfolded.

tomasrojo · 27-07-2018 02:13PM

magicbastarder wrote: »

i wonder/worry how much the fact that the 'drivers' knew they were being tested would skew the results - even if they might not have known they were specifically being tested on the cyclist visibility issue.

That's mentioned in the Australian study where people drove around a track at night and looked out for cyclists wearing different conspicuity aids. They found the drivers were good at spotting even people wearing no conspicuity aids at all, which might have been because the drivers were in a test scenario and on their mettle.

But when you combine a study like this recent one with the prospective cohort study in Nottingham (following urban cyclists who wear hi-viz and who don't and comparing their subsequent rates of collision), you get a convincing enough case that hi-viz isn't remotely as effective as frequently made out (often it's claimed to be so effective, and cyclists without it so hard to see that it's "essential" or "vital", and basically a moral imperative to wear it).

Hurrache · 18-09-2018 11:24AM

The Office of Emergency Planning has an interesting take on winter planning

https://twitter.com/emergencyIE/status/1041988691462377473?s=19

conkennedy · 18-09-2018 11:27AM

http://gifly.com//media_gifly/0/f/E/R/b/0fER.mp4

Pinch Flat · 01-10-2018 08:08PM

https://www.broadsheet.ie/2018/10/01/intolerable/

Free hi-vis jacket in Daily Fail today, life saving apparently. Headline is pretty sad as well. Poor woman.

Hurrache · 01-10-2018 08:13PM

Does it inflate on contact with water those nasty unapproved ones?

CramCycle · 02-10-2018 10:22AM

Pinch Flat wrote: »

https://www.broadsheet.ie/2018/10/01/intolerable/

Free hi-vis jacket in Daily Fail today, life saving apparently. Headline is pretty sad as well. Poor woman.

The irony being the one in the picture looks like one of the recalled ones. As the reflective strips are not reflective.

Pinch Flat · 22-10-2018 11:16PM

Piece on crime call just now, some Garda on recommending hi-vis for pedestrians as the evenings draw in. “There really is no excuse and it’s irresponsible to go walking without a hi vis. You can get a vest free off the RSA”. (Some paraphrasing)

So there you have it. Officialdom says tough luck if you’re walking home and get hit when you’ve no hi vis.

Absolutely no mention of motorists altering behaviour. Slowing down? Driving to the road conditions? Make sure you’re not distracted with a Phelan? No mention of ensuring the criticality of ensuring the left head lamp especially works (although they did have about 30 seconds on basic maintenance of your car that’s includes making sure your lights work - DUh!).

tomasrojo · 23-10-2018 12:02AM

The thing that intrigues me is whether they really expect people to do it in large numbers, or do they just enjoy hectoring people? I mean, do they really expect in a few years to traverse a town centre on a Friday night and see everyone dressed like a construction worker or a bin man? Really?

greenspurs · 23-10-2018 09:03AM

Can ANYONE on here actually admit that wearing hi viz jacket/vest/clothing at dusk or at night, actually does make you more visible?

When i go for a walk in the evenings, i wear a viz vest, to increase my visibility .When i cycled in low light i wear a hiviz gilet.

Why cant people on here admit that, instead of digging their heels in, just to create/fight an arguement!

magicbastarder · 23-10-2018 09:08AM

yes, i will say that a hi-vis jacket makes you more visible.
that's not the crux of the issue that gets people's back up though. go two posts up and you'll see the general argument which is not about whether they make you more visible.

RobbieMD · 23-10-2018 09:18AM

Pinch Flat wrote: »

Piece on crime call just now, some Garda on recommending hi-vis for pedestrians as the evenings draw in. “There really is no excuse and it’s irresponsible to go walking without a hi vis. You can get a vest free off the RSA”. (Some paraphrasing)

So there you have it. Officialdom says tough luck if you’re walking home and get hit when you’ve no hi vis.

Absolutely no mention of motorists altering behaviour. Slowing down? Driving to the road conditions? Make sure you’re not distracted with a Phelan? No mention of ensuring the criticality of ensuring the left head lamp especially works (although they did have about 30 seconds on basic maintenance of your car that’s includes making sure your lights work - DUh!).

Wasn't there a national slow down day the other day for motorists?

check_six · 23-10-2018 09:23AM

greenspurs wrote: »

Can ANYONE on here actually admit that wearing hi viz jacket/vest/clothing at dusk or at night, actually does make you more visible?

When i go for a walk in the evenings, i wear a viz vest, to increase my visibility .When i cycled in low light i wear a hiviz gilet.

Why cant people on here admit that, instead of digging their heels in, just to create/fight an arguement!

The whole thread goes through the different issues, but in brief, the problem is that the RSA promote the hi viz vests as a panacea for EVERYTHING.
Cycling in low light - hi viz vest.
Walking anywhere - hi viz vest.
Speeding motorists - hi viz vest.
Motorists on mobiles - hi viz vest.
Angry taxi drivers - hi viz vest.
Irish football team's inability to create scoring chances - hi viz vest.

The importance given by the RSA to hi viz vests vastly outweighs their efficacy. On a bike or on foot at night get a light first. If your brakes need fixing, do that before reaching for the hi viz. Also, hi viz is now ALWAYS mentioned in accident reports, when it should be entirely peripheral. This leads to victim blaming.

There's more, but you may have to read back over the thread to find the different nuances.

Grassey · 23-10-2018 09:26AM

greenspurs wrote:

Can ANYONE on here actually admit that wearing hi viz jacket/vest/clothing at dusk or at night, actually does make you more visible?

In all situations? Or limited situations?

CramCycle · 23-10-2018 09:28AM

greenspurs wrote: »

Can ANYONE on here actually admit that wearing hi viz jacket/vest/clothing at dusk or at night, actually does make you more visible?

When i go for a walk in the evenings, i wear a viz vest, to increase my visibility .When i cycled in low light i wear a hiviz gilet.

Why cant people on here admit that, instead of digging their heels in, just to create/fight an arguement!

They are also specifically designed for daytime visibility or when full beams are shone on them, not the scenarios that the RSA recommends.

The truth of the matter is that in regards cycling, good lights trump Hi Vis any day. Lights are already a legal requirement. Yet for some reason, the RSA seem to promote a sub standard safety item instead of promoting the items that are already required under law.

magicbastarder · 23-10-2018 09:32AM

and you can see it in court cases or inquests where it is frequently noted that a cyclist 'was not wearing hi vis' even though it's broad daylight.
and in one of the more recent ones, the motorist clearly stated he'd seen the cyclist anyway.

Hi vis discussion thread (read post #1)

Comments