In a risk assessment, can the severity rate change once additional control measures are in place? To my understanding severity rate remains unchanged only the Likelihood will be reduced. Do enlighten me.

I agree and I was going to use a similar analogy. I think it is dependent on the hazard as well as the control measures in place

I would also agree, the severity rate can change. For instance, working at height on a platform. If the control measure was to remove the requirement for this work to be done or for it to happen at ground level, then the severity would be nil.

Now just to find these miracle control measures!!

Always an interesting debate this one, especially the hi-vis issue. Will the severity always be the same? I would disagree. If the driver sees the hi-vis and applies the brakes earlier than he might if hi-vis was not been worn, but still hits the person, the collision would be at a lower speed and the severity may be reduced.

Typically,

Prevention controls are typically directed at reducing the likelihood of the scenario

Alerting controls (alarms) typically provide indication that an abnormal situation is developing and provide an opportunity to intervene. Alerting measures may be preventing or mitigating.

Mitigation controls are typically directed at reducing the consequences of the scenario

I can't believe I am reading here that hi-vis can reduce the potential severity of an incident (vehicle vs person). Severity can only be reduced by reducing the hazard.

Please look at previous discussions on this topic. Things said on this thread so far do not reflect the usual consensus.

I would agree with both Andy & Toe.

Even if u wear a hi-Viz which is a additional control measure, i would say that severity rate won't change it would only reduce the likelihood of the accident happening. Even if the driver slows down and still a collision happens the possibility of fatality is there.

My point here is severity would remain the same and won't change.

Thank you all for the replies.

I see where you are coming from with this argument, however I think this is overthinking it. A high vis jacket is not there to protect the user from physical damage. Therefore, in my opinion, it can only ever reduce the likelihood not the severity.

On the flip side of that coin, a hard hat will only ever reduce the severity. Wearing a hard hat will not make it less likely that one your esteemed colleagues working on that scaffold drops a tool which hits you on the head, but it will absorb some of the impact. Thus the severity is reduced but not the likelihood.

In my experience, this is where most people fall down with their risk assessing. For example they might say:
Hazard: Falling object - Sev: 5, Prob: 5 = 25
Control: Hard Hat (re-assess risk) - Sev: 3, Prob 3 = 9

They reduce the probability where it will be unaffected, so that second line should read:
Control: Hard Hat (re-assess risk) - Sev: 3, Prob 5 = 15
(Forgive me if I am preaching to the converted...)

Of course they may be controls which reduce the probability and the severity but these are not easy to come by and it is for this reason that one control is never adequate. To use my above example of a falling tool, there is no way any H&S professional would ever say "Ah stick a hard hat on that will do for that hazard!", no, we insist on toe boards, lanyards, training and hard hats - all of those controls reduce the severity and the probability. Never be content with reducing one without the other, I always try as best I can to reduce both!!

Ray - I quite agree - hence the 'm' in the equation E = 1/2mv^2

A nice summary here for the risk of pedestrain fatality probability from vehicle impact speed.

http://www.who.int/viole...orld_report/speed_en.pdf

For construction/vehicle yard areas - I think bigger risk factors per se are standing behind reversing vehicles, standing in blind spots for drivers/pedestrains/trap points, un expected movement of vehicles.

If you can't be seen, a hi vis jacket isn't going to save you from being crushed.

Hi all,

Though it is quite old topic seen by me today. My response to this goes as follows:

Risk = Severity x Likelihood

The Risk reduced by reduction of any of these two i.e. Severity or Likelihood.

Now it is important to understand the difference between Risk and Hazard. In the earlier example quoted of person got struck to vehicle, the hazard is vehicle and risk is getting injured. Now you can eliminate any one of the thing to make thing safer.

To remove / reduce the hazard, you can have underground / overground crossing of road, foot path with protection railing etc etc. With these type of control measure you are reducing / eliminating hazard hence likelihood will get changed and at the same time the severity will also get changed.

To remove / reduce the risk, you can have zebra crossing, Hi-vis, speed breakers etc. In such type of control the person still get hit by vehicle but the quantum of injury will be quite low as the speed of vehicle may be low in such cases. Hence this will keep likelihood same but severity will reduce.

Finally if you are removing the hazard itself then likelihood and severity both will affected and if you are reducing the risk then only severity will change.

Similarly for other example of working at height. The Hazard is working at height and risk is falling from the height.

In this case the Hazard can be removed by providing working platform or carrying out the job at ground level. With such control measure the likelihood will change along with the severity.

However if the control measure is just safety harness, safety net etc then the likelihood will remain same and only severity will change.

So always look at the risk from this angle, while making the risk assessment.

Smurf, if hi-vis clothing is not classified as PPE, what would it be classified as?

Nonsense ... a Hi Viz vest makes you invincible instead of invisible, every desk jockey knows that! ;-)

During site inductions the script now tends to be "the Hi-Vis you are being asked to wear by our corporate policy won't stop the FLT from hitting you, but it will protect the value of your payout in event of a claim"

Given the tatty, non-reflective, grease sodden garments some contractors and visitors cheerily arrive with (whilst their desk jockey H&S Manager happily shuffles his signed company PPE issue forms) the anecdotal evidence is correct Hi-Vis should not be considered PPE as many companies fail to monitor and maintain the issued device.

This lengthy thread takes me back 18 years to my first cieh risk assessment course .. Far too much time debating around qualitative risk assessment. Anyone with a level maths understands quantitative risk assessment regarding probability etc.,



love the phrase 'desk jockey'....

And, if you are not careful you will end up putting that every possible risk could result in death, thus rendering the whole process a complete and utter waste of time

Watson & sadlass,

Not at all. If you do a RA properly you do what's reasonable, significant risks, and with any traffic accident I think it is reasonable to expect the worst case, unless you're in a desert!

Firstly, I'm not sure why being in a desert would alter the severity of a collision with a vehicle? Likelihood - yes; severity - no.

Secondly, it is very sloppy work to just simply accept the worst case scenario and move on. This just assumes that everyone hit by a car simply dies no matter the circumstances (e.g speed, etc), thus rendering the whole process a complete and utter waste of time.

Excerpt from RAC website showing fatalities as accounting for less than 1%:

There were 1,732 people killed in road accidents reported to the police in 2015.

The number of people seriously injured in reported road traffic accidents decreased by 3 per cent to 22,137 in 2015, compared with 2014.

There were a total of 186,209 casualties of all severities in 2015.


- See more at: http://www.racfoundation.../motoring-faqs/safety#a1

Please pay attention, there are no kerbs to bang your head on in the desert :0)

So, for workplace traffic, like in a loading yard, building site or roadworks I think we would come up with the same risk assessment.

Cheers.