Case No: B3/2003/0397/0703/0704
Neutral Citation Number: [2004] EWCA Civ 374
IN THE SUPREME COURT OF JUDICATURE
COURT OF APPEAL (CIVIL DIVISION)
ON APPEAL FROM CARDIFF COUNTY COURT
(HIS HONOUR JUDGE HICKINBOTTOM)
Royal Courts of Justice
Strand, 
London, WC2A 2LL

Date: Tuesday 30th March 2004 
Before :

THE RIGHT HONOURABLE LORD JUSTICE AULD
THE RIGHT HONOURABLE LORD JUSTICE MAY
and
THE RIGHT HONOURABLE LORD JUSTICE SCOTT BAKER

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Between :

	KENNETH JOHN BROWN, LLOYD MICHAEL GROGAN AND PETER GODFREY TRICKEY	Appellants	
	- and -		
	CORUS (UK) LTD	Respondents	

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(Transcript of the Handed Down Judgment of
Smith Bernal Wordwave Limited, 190 Fleet Street
London EC4A 2AG
Tel No: 020 7421 4040,  Fax No:  020 7831 8838
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Nigel Cooksley Q.C and Ian Scott (instructed by Russell Jones & Walker) for the Appellants
Charles Feeny (instructed by Cartwright Black) for the Respondents

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Judgment

Lord Justice Scott Baker:

1.	This is the judgment of the court.
2.	On 13 February 2003 Judge Hickinbottom, sitting in the Cardiff County Court, dismissed the claims for damages of six former employees at the Llanwern Steelworks in South Wales. We have heard the appeals of three of those employees, Messers Brown, Grogan and Trickey. The other three employees’ claims failed on the ground of medical causation. They are of no direct relevance to the present appeals. The six individuals were selected as lead cases from some 57 similar claims. The outcome of the present appeals is therefore of some wider importance than to the three appellants.
3.	Each of the appellants suffers from a condition known as Hand/Arm Vibration Syndrome (“HAVS”), a condition caused by exposure to vibration from hand held vibratory tools over many years. HAVS is the generic term covering a number of specific conditions of which Vibration White Finger, the condition suffered by the appellants, is one.
4.	The Llanwern Steelworks closed in July 2001 although the Rolling Mills remained open thereafter. Since the 1960s they had been owned and operated by a succession of companies including the Steel Corporation of Wales, the British Steel Corporation, British Steel plc and finally Corus UK Limited who are the respondents to these appeals. Corus took over all relevant obligations and liabilities of its predecessors and nothing turns on the change of identity.
5.	In its heyday the operation at Llanwern was very considerable and employed thousands of men. During their employment in either the Refractory Department (responsible for removing and replacing the refractory material that lined much of the plant), or the Civil Engineering Department (responsible for demolishing and rebuilding various parts of the works) the appellants used a variety of handheld pneumatic mechanical tools in particular jackhammers and drills for removing or “wrecking” refractory material, rammers for installing malleable refractory material and concrete pokers to assist the de-aerating and setting of concrete.
6.	HAVS is a cumulative or progressive condition. Asymptomatic damage worsens as a result of exposure to vibration until it becomes symptomatic. The condition has a vascular and neurological element. The neurological element may develop independently from (or at a different rate to) the vascular element. The condition is dose related i.e. the more vibration to which the person is exposed, the greater the damage that is caused. The vibration dose is made up of three components (i) the vibration level experienced from the particular tool being used (ii) the daily exposure to that level of vibration and (iii) the cumulative exposure to that level of vibration. The amount of vibration experienced by an operator at any given time depends on a number of variables, including the nature of the job being done, the type of material on which the machine is operating and the grip of the operator. There are variables within the machine itself, including its weight, the length of action stroke (amplitude) and the number of beats per minute (frequency). High amplitudes and low frequencies produce greater vibration levels. Acceleration is directly proportional to the force produced on the hands and is expressed in terms of metres/second² (“m/sec²”).
7.	Brown, Grogan and Trickey all worked in the Refractory Department as labourers. Brown worked there from 1971 – 2000, Grogan from 1977 – 2000 and Trickey from 1964 – 2000. Grogan had previously worked in the Civil Engineering Department from 1969 – 1977. The judge found that until about 1982 more than half of a labourer’s time in the Refractory Department was spent using heavily vibrating tools. After 1982 the proportion dropped and continued to fall over time until the works closed in 2001. When Grogan worked in the Civil Engineering Department he spent about the same amount of time working with vibrating tools as he did in the Refractory Department i.e. about 3 - 4 hours per shift. This was translated to 2 hours per day ‘anger time’ mainly with jackhammers.
8.	The judge found that Brown’s exposure to vibration was 12.9m/sec² from 1971 to 1982, thereafter falling to 10.5m/sec² by 2000 when he left the respondent’s employment. He found that Grogan’s was 11.6m/sec² from 1969 to 1977 (when he worked in the Civil Engineering Department) rising to 12.9 m/sec² from 1977 to 1982 and then falling to 10.5m/sec². He found that Trickey’s exposure was 12.9m/sec² from 1964 to 1982 thereafter falling to 10.5m/sec² by 2001. The judge also found that each of the appellants developed neurological damage, but not vascular damage, as the result of their use of vibratory tools. He said with regard to Brown:
“Whilst, on the evidence, I am not satisfied that Mr Brown has suffered any loss of strength in his hands, or general pain in hands and arms, as a result of exposure to vibration, I am satisfied that he does suffer from low grade symptoms of numbness and tingling in all of his fingers, now on a persistent (as opposed to intermittent) basis, which are attributable to vibration. Dr Cooke concluded that Mr Brown was “describing sensorineural changes due to hand arm vibration exposure” (Report, 5 July 2000, Paragraph 6.17). I accept this conclusion. I accept Dr Cooke’s evidence that, because of their nature, such symptoms will not improve following cessation of exposure (and neither will they deteriorate, unless there is further exposure to vibration), and the symptoms and their level are therefore permanent.
In classifying such symptoms, as they are restricted to the sensorineural, the Taylor Pelmear Scale is not helpful (although, on that scale, they would technically be classified as Ot/On). As I have explained, the Stockholm Scale is a coarse one, as it seeks to pigeon-hole cases into a particular category, although the scale is in reality a continuous linear one. The difference between 2SN and 3SN is, formally, the addition of problems of “tactile discrimination” or “manipulative dexterity”. In this case, I find there is some evidence of such additional problems, but the evidence comes from only the (appellant) himself, is limited, and is made difficult to assess positively because of Mr Brown’s other, unrelated complaints (e.g. loss of grip strength and general upper limb pain). Whilst I accept this is a borderline case, such problems are, in my view, poorly evidenced and, on the available evidence, insignificant.
For these reasons, I would categorise Mr Brown (as does Dr Cooke) ROV 2SN LOV 2SN, on the Stockholm Scale.” 
And with regard to Grogan:
“On the basis of all the evidence, I am satisfied that the sensorineural symptoms of which Mr Grogan complains were caused by the vibration to which he was subjected whilst in the employ of Corus.
…….
On questioning by Dr Cooke for the purposes of his report, Mr Grogan indicated that lack of sensitivity in his fingers had not resulted in any inability to, e.g., play darts. Having considered all of this evidence, I am not satisfied that the sensorineural symptoms of which Mr Grogan complains has led to any significant practical disability on his part.
As in Mr Brown’s case, on the Taylor Pelmear scale, Mr Grogan’s symptoms would be categorised as Ot/On: and, more helpfully, ROV 2SN LOV 2SN, on the Stockholm scale. Because of the lack of compelling evidence of reduced “tactile discrimination” or “manipulative dexterity”, I do not consider a classification of the sensorineural symptoms to category SN3 to be warranted.”
And Trickey:
“I find that he has suffered from persistent numbness, with reduced tactile discrimination and manipulative dexterity. Dr Cooke says that the formal test suggested a Stockholm Scale grading SN3, for each hand. Mr Trickey’s account of his problems – which, in substance, I accept – supports that classification.
For these reasons, I would categorise Mr Trickey as ROV 3SN LOV 3SN, on the Stockholm Scale. The sensorineural symptoms to which I have referred were caused by vibrating tools, operated by Mr Trickey in the course of his employment by Corus at Llanwern.”
The R and L in these classifications refer, of course, to the right and left hands.
9.	The judge therefore concluded that each appellant suffered from sensorineural symptoms in the fingers but that none of them suffered from blanching in a manner diagnostic of HAVS. They did not therefore register on the vascular component of the Stockholm Scale used to measure the condition. The stages in the vascular component are as follows:
Stage	Grade	Description	
O		No Attacks.	
IV	Mild	Occasional attacks affecting only the tips of one or more fingers.	
2V
	Moderate	Occasional attacks affecting distal and middle (rarely also proximal) Phalanges of one or more fingers.	
3V	Severe	Frequent attacks affecting all phalanges of most fingers.	
4V	Very severe	As in stage 3 with trophic changes in the fingertips.	

The stages in the sensorinenal component are:
Stage	Description	
OSN	Vibration-exposed but no symptoms.	
ISN	Intermittent numbness with or without tingling.	
2SN	Intermittent or persistent numbness reducing sensory perception. 	
3SN	Intermittent or persistent numbness reduced tactile discrimination and/or manipulative dexterity.	
10.	The judge noted that a lot of research had been done on the aggregate ‘vibration dose’ necessary to cause the syndrome but that whether a particular employee suffers from symptoms of the syndrome depends upon, not only the vibration dose to which he is exposed (a product of the vibration level of the machines he has used and the time he has actually used them (i.e. the ‘anger time’)) but also his own idiosyncratic propensity to be affected. Particular individuals may be exposed to high levels of vibration over a lengthy period, but suffer no symptoms. Others may be exposed to relatively low levels of vibration for a relatively short period and suffer symptoms. Also, the damage that gives rise to the syndrome may remain asymptomatic for a considerable period. During this period there is no means of telling what (if any) damage has been caused. However, as the damage is caused by the cumulative effect of exposure to vibration, once that exposure ceases the adverse effects plateau or some may even regress. It is highly unusual for symptoms to worsen after the exposure to vibration is removed.
11.	There is no doubt that each of these appellants’ exposure to vibration greatly exceeded the recommended maximum.
12.	The judge correctly observed that in order to succeed in their claim for negligence each appellant had to show that at the relevant time there was a foreseeable risk of injury arising from his use of vibrating tools. A number of admissions were made by the respondent before and during the trial. These included:
•	“That (the respondents) ought by 1 January 1976 to have been aware of the risk of injury from vibratory tools.
•	That if it is shown by any claimant that his vibration exposure after 1 January 1976 for any period exceeded the contemporaneous recognised safe levels, (the respondents) will accept this would represent a breach of relevant common law and statutory duties owed by (the respondents) to this claimant. (By recognised safe levels, (the respondents) mean those laid down in DD 43 of 1975 and then those laid down in BS 6842 of 1987).
•	That, if such a breach of duty is proved, then (the respondents) ought, in respect of the relevant exposure, to have considered and taken, as appropriate, the steps recommended in DD 43 of 1975 and BS 6842 of 1987 respectively.” 
The respondents indicated they did not intend to advance any positive case in relation to the steps in fact taken.
13.	The respondents in due course accepted that on a daily basis, the individual appellant’s vibration exposure was likely to have been unacceptable within DD 43 of 1975 and exceeded the action level within BS 6842 of 1987, and that having regard to the terms of their earlier admission there was therefore an admitted breach of duty in each case. Indeed on the third day of the trial the respondents informed the court that: “on any assessment of the claimants’ evidence their vibration exposure was sufficient to create a foreseeable risk of injury as from 1 January 1976”.
The judge found:
“The (respondent) was a major employer of men who used vibrating machines during the course of their employment. It had a representative on the drafting committee for DD 43, who would have had drafts of the guidance well before its publication. There is little doubt that the company must have had actual knowledge of the paper by February 1975. I find that, by February 1975, the (respondents) were not only aware of the risk of injury through use of vibrating tools but, on the balance of probabilities, they had actual knowledge of the information and guidance contained in DD 43 with regard to that risk. In so far as they did not have actual knowledge, they clearly had constructive knowledge.”
14.	He also found that the respondents ought to have conducted a survey of vibrating tools in use at Llanwern; that they should have provided training in the use of the tools, have introduced a system of medical surveillance and have positively monitored employees at risk and sought out symptoms.
15.	The appellants’ claims failed for two reasons. The first was because the judge decided that the respondents owed no duty to them to reduce the levels of vibration to which they were exposed either by using alternative machines or changing the work systems. He said:
“Therefore, although the (appellants) strenuously submitted that, in addition to the (respondents’) obligations to monitor and warn (which, largely, the (respondents) had accepted by the end of the trial), the (respondents) had an obligation to reduce the levels of vibration suffered by individuals by substantial changes to the tools used and work practices, on the evidence, I cannot be satisfied that such an obligation arose in the circumstances of this case. The (respondents) had a duty to consider and investigate these matters: but, had they done so, in my judgment, absent any indication that the projected risks of HAVS were playing out at Llanwern – absent a single case of symptomatic HAVS in the relevant departments – on the evidence, I find that the results of such an investigation would not have been reasonably to require the (respondents) to take steps to reduce the vibration levels by changing machines or work practices.”
The second was that the respondents’ failure to comply with such precautions as he had held they were under a duty to undertake i.e. proper use of the tools, training and medical surveillance was not causative of their injuries because if the precautions had been undertaken the injuries would have been no different.
He said:
“I have found that the (respondents) should have provided training – e.g in how to use the machines, with a loose grip etc- but, again, there is no evidence as to the effect, if any, any such training might have had. There is no evidence as to what the training would have comprised, or how it might have been effective in reducing the vibration dose for any employee. Indeed, there is no evidence upon which I could conclude that had the (respondents) complied with their training obligation, the vibration dose of any employee would have been reduced.”
And a little later:
“In considering the factual causation, one has to assess an imponderable: what would a particular (appellant) have done if the (respondents) had not been in breach of their duty, i.e. if the (appellant) had been warned and medically monitored as he should have been? This is a very difficult question to consider. Evidence from the (appellant) himself that he would have taken action to avoid the risk (e.g. by finding alternative employment, without that risk) is of little weight, no matter how sincere the (appellant) might be, because of the difficulties of giving objective evidence where the temptation unwittingly to give self-serving evidence is obvious.”
Then he said:
“The (appellant) must show that, had the (respondents) not breached their duties to him, he would not have suffered injury at all, or at least he would not have suffered the same extent of injury”
16.	It is, at first blush, a somewhat surprising finding that the respondents were not under a duty in some way to reduce the level of vibration exposure suffered by the appellants bearing in mind the finding that because of excessive exposure each of them suffered significant symptoms of HAVS. Mr Nigel Cooksley Q.C, who appeared for the appellants, has pointed out that all three of them were young and fit and did more than their fair share of work involving vibration exposure. It was submitted to us that there was an admitted breach of duty and that in the light of the admissions breach of duty was never really in issue. Mr Charles Feeny, for the respondents, says that while some breach of duty was admitted there was always an issue as to the extent of it.
Duty to reduce the levels of vibration exposure
17.	Safe levels of vibration exposure were identified as those laid down in DD 43 of 1975 (the draft for the development of a British Standard) and subsequently BS 6842 of 1987, the substance of which found its way into a Health and Safety Executive Booklet in 1994 and it is said that the respondents ought in respect of the relevant exposure to have taken, as appropriate, the steps recommended in DD 43 of 1975 and BS 6842 of 1987.
18.	The respondents’ admissions contained, however, this important reservation:
“The extent of the breach, that is what steps could reasonably have been expected to have been taken remains in issue. This is important in the context of causation as the (appellants) must show that such steps as the (respondent) could reasonably have been accepted to undertake would have avoided the condition in their case.”
19.	Mr Cooksley makes the point that the admissions appear to accept that the respondents were under a duty to take the steps referred to in the documents and that there was a duty to reduce the level of vibrations. The experts produced a joint statement setting out their areas of agreement and disagreement. One of the areas of agreement was that it would not have been practical to reduce the vibration magnitudes to below those capable of causing vibration-induced injury. However, it was not disputed that it was possible nevertheless to reduce the vibration levels very significantly.
20.	There were the following important points of agreement:
•	“If the court accepts the (appellants’) evidence, then we agree that the (respondents) should have introduced the full range of preventative measures identified in standards….
•	Reductions in the vibration magnitude would be expected to delay the onset of vibration-induced injury.
•	Reductions in exposure duration would be expected to delay the onset of vibration-induced injury”.
21.	DD 43 of 1975 makes the point that it is important for employers, operators of tools and medical experts to be able to understand the level of reduction in vibration and the working methods which are required to manage the effect of the residual vibration. Appendix B of the document sets out measures, which may help to reduce the incidence of vibration. These include under ‘Working Technique’.
a)	The weight supported by the operator’s hand should be as low as possible with the tool resting on the workpiece or on a support as much as possible,
b)	Tools should be held as lightly as possible consistent with proper control.
22.	And under ‘Working Method’: 
a)	The working system should be designed to provide as many breaks as possible for other work not involving vibration.
b)	It may be practicable to alternate the use of the tool with two or more other operators during the working day.
c)	Certain tools must not be run at working speeds if they are not contact with the material.
23.	In BS 6842 of 1987 under the heading “Guidelines on Prevention Procedures” it is suggested that the vibration should be measured and where appropriate a reasonably practicable process should be chosen to minimise vibration exposure. There is also detailed advice for those who use vibrating hand tools and suggested administrative preventive measures including training and work schedules with rest breaks.
24.	When counsel for the respondents came to make his closing submissions before the judge he put his client’s position as follows:
“Breach of duty. The (respondent), admits that the level of risk called for warning and monitoring. The (respondent) contends that given the level of appropriate risk and intrinsic difficulty in reducing vibration exposure they were not in breach of duty in failing to reduce exposures further then they were in fact reduced on the evidence.”
25.	The respondents chose not to call any evidence at the trial. If they wished to show that for some reason it was impractical to reduce vibration exposure or that there was some intrinsic difficulty about doing so then it seems to me it was up to them to establish this. The position in which they left the judge, having called no evidence, was quite simply that there was no evidence of impracticability or intrinsic difficulty. 
26.	The judge found the steps the respondent ought to have taken to be clear. They were:
i)	To have conducted a survey of vibrating tools in use at Llanwern.
ii)	To have pre–screened employees.
iii)	To have introduced a system of medical surveillance.
iv)	To have warned employees of the risks of contracting HAVS as a result of using vibrating tools.
v)	To have provided their employees with information concerning HAVS and information and training in the use of tools.
vi)	To have considered introducing tools with the lower vibratory levels.
vii)	To have considered introducing systems designed to reduce vibration exposure in individuals, e.g. requiring breaks, insisting on job rotation and limiting the overtime done by any one individual. 
27.	The appellants’ argument is that these findings did not go far enough. There was clear evidence on which the judge should have found a duty to decrease vibration levels to which the appellants were exposed. The respondents’ case was that although they were aware of the importance of reducing vibration exposure by work practices where possible, no consideration was given to altering work systems with a view to achieving such a reduction. Their argument was that, absent any evidence of employees suffering from symptoms at Llanwern, it was reasonable for them to take no steps to reduce vibration levels. The judge held they ought to have considered the issue within a reasonable time of the publication of DD 43 of 1975, say by 1978. He then went on to consider what the outcome of such an exercise would have been. It is at this point that in our judgment he fell into error.
28.	It is important to bear in mind the following findings about the appellants’ evidence. There were no formal work rotation schemes. The culture of the workplace was for the younger and fitter men to do a disproportionate share of the work using vibratory tools rather than require their older colleagues to do their share. If a particular employee considered he was good with a machine he tended to use that machine more than others. There was an incentive to take overtime in which an employee simply did a double (16hr) shift. Grogan said that in order to ensure premium rate overtime on a Sunday employees were required to work at least two double shifts during the week. The system appeared to encourage heroic hours of work with the necessary vibrating tools rather than seek to limit such hours.
29.	The other matters the judge said he took into account were as follows:
(1) That the advice in DD 43 and BS 6842 was not mandatory and had to be considered in the context of the individual case and the knowledge of the employer of the specific circumstances of that case.
It is not clear to us what the judge meant in this regard other than that it might in the circumstances of a particular case be appropriate to leave vibration exposure levels higher than would normally be appropriate.
(2) Professor Griffin’s (the appellants’ expert) evidence that the (respondents) “should have instituted a scheme for monitoring and preventing excessive durations of exposure to vibration. This should, have been applied so as to prevent excessive tool use by any individual in a gang. The restrictions should have applied to the daily use of tools…….including their use when undertaking overtime in addition to normal work”.
The judge, however, appears to have ignored this evidence.
(3) In the 1980s, for a variety of reasons, the use of heavily vibrating tools fell with a consequent lessening of risks for employees. In 1988 new work systems reduced the amount of refractory work. But there was no evidence whether those steps could have been taken earlier and if so at what cost. 
We cannot see how this advances the respondents’ case.
(4) There was among the documents a memorandum from Dr Sinclair dated 2 December 1982, which spoke of reducing times per shift or additional rest periods and alternative employment, but said that these “clearly had industrial relations implications taking into account the lack of alternative work and the individual’s wish to maintain earnings.” The judge said this was some contemporaneous evidence of potential difficulties the respondents faced in significantly altering work patterns.  
This memorandum, however, related to the works at Scunthorpe. The respondent called no evidence about it and there was thus no evidence as to its provenance.
(5) Until the 1990s there was no evidence of any problems arising from the use of vibrating tools at Llanwern despite the fact that many employees had used such tools for many years.
However, as Mr Cooksley observed, this point is circular. You don’t know if there is a problem unless you enquire and the respondents should not have stood by and done nothing.
30.	The judge went on to balance the safety of the employees with the reasonableness of expenditure in protecting them. Here he took into account the following:
(1) HAVS began with very minor, intermittent, symptoms. They were relatively minor and could be halted by early detection.
This is correct. The condition gives rise however to latent damage before symptoms appear. What matters is how soon the condition is identified and exposure to vibration tackled.
(2) The absence of evidence of any employee at Llanwern suffering from HAVS despite many years use of heavily vibrating machines. 
The answer to this is that the respondents never enquired.
(3) There was at least a real possibility of considerable resistance to a change of working practices. For example a restriction of the availability of overtime, could have led to a reduction of an individual’s earnings.
There is in our judgment force in the appellants’ submissions that it was not open to the judge to reach such speculative conclusions. It was up to the respondents to call evidence about what was, and more particularly was not, practicable. As we have already mentioned these appellants did more than their fair share of the work with the heavier vibrating machines.
(4) The absence of evidence of alternative machines or practical technology at that time to design machines with substantially, lower vibration level.
It is common ground that there were no alternative machines available at the time.

(5) The cost of steps that could be taken.
The judge pointed out there was no evidence from either side. But he went on to say that a restriction of working time or limiting the amount of anger time would be likely to have increased labour costs. Importing fully mechanical alternatives to the hand held tools would have meant a greater capital cost, but there was no evidence of what it might have been or its impact on manning levels. The cost and negative impact of such steps could have been very significant.  
31.	We do not consider it was open to the judge to take into account the cost and impact of reducing vibration levels without any evidential basis for doing so. The vibration levels were dangerously high. It was up to the respondents to do something about them. What they did was up to them. If, in truth, their case was that it was impractical to do anything significant then it was necessary for them to justify this by calling evidence. Reduction of vibration levels was the most basic step of all. The judge found the respondents in breach of duty in failing to take other steps but not in failing to take this step. In our view he was wrong.
32.	There was clear evidence on which he should have found a duty to decrease the vibration level. We are fortified in our view by the observation of Judge L.J. in Armstrong and Others v British Coal Corporation 1996 (unreported) CA at p.20 where he said that after January 1976 any level of exposure in excess of that advised in the 1994 handbook required job rotation in addition to warnings, surveillance and other precautions and at p.21 that a “preventative programme” (which includes job rotation) should be introduced where it is known that vibration exposure will exceed the ‘action level’, A8 2.8m/s². Judge L.J went on to say that if the employee’s vibration levels exceeded A8 2.8m/s² for any significant period of employment, the fact that an individual employee’s lifetime exposure fell below A8 2.8m/s² would not provide the defendants with an unanswerable defence to a claim based on negligent failure to reduce exposure.
33.	Further support is found in the judgment of Pill L.J. in Smith v Wright and Beyer [2001] EWCA CIV 1069. At para 18 he said:
“The judge……was entitled to reach the conclusion that in 1977 it was open to the defendants, had they wished to discharge the duty on them as employers, to have reorganised their working practice so as to reduce exposure to vibration and hence the claimant may not ever have reached the stage when he would have experienced symptoms”.
And at para 20:
“By the expression “reservoir” the judge was referring to C’s reservoir of tolerance which until full produces no symptoms.”
34.	The fundamental difficulty we find with the judge’s approach is this. Once he concluded the appellants had been subjected to excessive levels of vibration the burden shifted to the respondents to justify why that situation was allowed to continue. It was not open to the judge to speculate on matters such as cost and resistance to change in working practices. These were matters which required evidence if the respondents wished to use them to justify  maintaining unchanged the excessive level of vibration. There are many different ways in which an employer can create a safe system of work for an employee. The choice of how it is to be achieved lies with him. It is not open to him to provide a system that is unsafe and fail to improve it expecting the employee to justify what should have been done. In our judgment the respondents were in plain breach of duty in the present case and should have taken appropriate steps to reduce the vibration levels. 
Causation
35.	Having found, erroneously in our judgment, that the respondents owed no duty to the appellants to reduce vibration levels, the judge went on to say that even if there had been such a duty the engineering experts could give no indication of the reduction in vibration magnitude or exposure time that could have been expected from such steps. Accordingly, even assuming a breach of duty, the appellants would have faced very considerable, and probably insuperable, difficulties in relation to causation. We cannot agree with this. We have already set out in para 19 the main points of agreement between the experts and we do not repeat them.
36.	If there had been a delay in the onset of symptoms, submits Mr Cooksley, the odds are that these three appellants would not have developed symptoms at all. He points to the dates that the appellants did in fact develop symptoms. These were: Brown 1996, Grogan 1992, Trickey 1995 or 1996. We think there is some force in this although the very nature of the condition makes it to an extent speculative what would have happened in circumstances that did not occur. But, submits Mr Cooksley, the law does not require the appellants to go any further than to show that by failing to reduce the level of vibration the respondents were exposing them to an increased risk of suffering from the condition from which in the event they suffered.
37.	It does not appear that the relevant authorities were cited to the judge, but we do not think there is any significant disagreement between counsel about the principles that apply. The leading authority is McGhee v National Coal Board [1973] 1 WLR 1 which was endorsed by the House of Lords in Fairchild v Glenhaven Funeral Services Ltd [2003] 1AC 32. The appellants do not have to show to what extent the reduction in vibration levels would have made a difference. By doing nothing the respondents materially increased the risk to the appellants.
38.	In McGhee the appellant, who succeeded unanimously in the House of Lords, suffered from dermatitis which was admitted to be attributable to working in his employers’ brick kiln. The breach of duty relied on was the failure to provide adequate washing facilities. The claim failed because the judge was not satisfied the appellant had shown on balance of probabilities that that breach of duty caused or materially contributed to his injury. It was held on appeal that, although the medical evidence could not establish that had the appellant been able to wash immediately in showers provided by his employers he would not have contracted the disease, yet, in the absence of complete medical knowledge of all the material factors relating to the disease, there was no substantial difference between materially increasing the risk of injury on the one hand and making a material contribution to the injury on the other. There was an admitted breach duty and the employers were liable for an injury within the risk, which they had created. 
39.	Each of their lordships put his reasoning slightly differently. At 4D Lord Reid referred to Bonnington Castings Ltd v Wardlaw [1956] AC 613 and said:
“There the pursuer’s disease was caused by an accumulation of noxious dust in his lungs. The dust which he had inhaled over a period came from two sources. The defenders were not responsible for one source but they could and ought to have prevented the other. The dust from the latter source was not in itself sufficient to cause the disease but the pursuer succeeded because it made a material contribution to his injury.
The respondents seek to distinguish Wardlaw’s case by arguing that then [sic] it was proved that every particle of dust inhaled played its part in causing the onset of the disease whereas in this case it is not proved that every minor abrasion played its part.”
He said at 5A that he could not accept a distinction between materially increasing the risk that the disease will occur and making a material contribution to its occurrence.
40.	Lord Wilberforce said at 7E that in the absence of proof that the culpable addition had, in the result, no effect, the employers should be liable for an injury squarely within the risk which they created and that they, not the pursuer, should suffer the consequence of the impossibility, foreseeably inherent in the nature of his injury, of segregating the precise consequence of their default.
41.	Lord Simon of Glaisdale said at 8E that in his view a failure to take steps which would bring about a reduction of risk involved, in that type of case, a substantial contribution to the injury.
42.	Lord Kilbrandon concluded that the appellant’s injury was more probably than not caused by his employer’s breach of duty.
43.	Lord Salmon said at 12G that where an employer’s negligence has materially increased the risk of an employee contracting an industrial disease then he is liable in damages to that employee if he contracts the disease notwithstanding the employer is not responsible for other factors which have materially contributed to the disease.
44.	McGhee was endorsed by the House of Lords in Fairchild. That case involved mesothelioma due to asbestos dust exposure at work. The case was complicated by the fact that there was more than one employment in which the claimant had been so exposed. Thus, McGhee is somewhat nearer to the present case on the facts. However, Lord Hutton said this at 92D:
“Where the claimant proves that the breach of duty materially increased the risk of the onset of the disease from which he suffers, it will be open to the defendant to adduce evidence and to argue that even though the breach of duty materially increased the risk, nevertheless the evidence on its behalf displaces the inference of causation”
45.	Lord Rodger of Earlsferry pointed out at 118E that the McGhee principle is designed to resolve the difficulty that arises where it is inherently impossible for the claimant to prove exactly how his injury was caused. It applies therefore where the claimant has proved all that he possibly can, but the causal link could only ever be established by scientific investigation and the current state of the relevant science leaves it uncertain exactly how the injury was caused.  He went on to say that part of the underlying rationale of the principle is that the defendant’s wrongdoing has materially increased the risk that the claimant will suffer injury and that it was essential the defendant’s conduct must have created a material of risk of injury to the claimant himself and been capable of causing the claimant’s injury. These observations seem to us to fit appropriately with the circumstances of the present case. The respondents knew that each appellant was being exposed over a substantial period of time to levels of vibration far in excess of the level considered to be safe. Yet they did nothing about it. The condition of HAVS is dose related and progressive but there is a variation in the reaction of individuals. What we think is plain in the present case is that by their wrongdoing i.e. in particular by failing to reduce the appellants’ vibration exposure, the respondents have materially increased the risk of the appellants suffering from HAVS or at the very least of their suffering from symptoms sooner than would otherwise have been the case.
46.	The judge does not refer to either of these authorities in his judgment and as we have said they do not appear to have been cited to him. The decision in Transco v Griggs [2003] EWCA CIV 564 post-dated the judgment in the present case. In that case the claimant suffered from palmar arm disease (PAD) another condition caused by the use of vibratory tools. Hale L.J, with whom Wilson J agreed, said this:
“In HAVS there is a recognised dose/response effect: so much vibration produces so much VWF. In PAD it is not possible to say how much vibration will produce the damage. Mr Cross acknowledged this in cross-examination. [Tp53]. This is scarcely surprising as PAD is so rare and the link with vibration is only just being recognised.
Hence it is argued that the claimant could not prove that PAD was caused by guilty, unacceptable, negligent levels of exposure rather than by innocent, non negligent, acceptable levels; and that the judge was wrong to regard this as covered by the principles in McGhee and Fairchild. In both of those cases, the risk – that brick dust could cause dermatitis and that asbestos could cause mesothelioma – was well known. In both of those cases there was a proven breach of duty, which could have caused that risk to materialise. In both of those cases the state of knowledge was such that the claimant could not establish it was that breach of duty which had caused his damage. In those circumstances, relaxation of the strict “but for” requirement of causation was justified. Those features, it is argued, do not apply here.”
47.	The court of appeal rejected that argument. Hale L.J continued:
“In any event even if the but for test could not be satisfied, there can be little doubt that the employer’s failure to have a proper system for detecting and preventing vibration induced diseases materially increased the risk of an employee sustaining such a disease. Once the degree of exposure, the breaches of duty and the medical causation had been established, it would be an unjust legal system which did not hold the employer responsible for what had happened. ”
Mr Cooksley points out that the issue was whether the judge was entitled to find PAD was caused by vibration exposure. It was a more difficult case for the claimant then the present one because PAD was not a known risk. Mr Cooksley also submits, with some force, that this is a stronger case than McGhee. There, there was only one breach of duty. Here there were several. 
48.	In our judgment, once the position is reached that the respondents were in breach of duty in failing to reduce the vibration levels to which these three appellants were exposed causation is established on the McGhee principle. By not doing anything about vibration levels (and there were a number of things that could have been done) the respondents materially increased the risk that the appellants would suffer from HAVS. Had they taken such steps they would have materially reduced the risk involved. Their failure to do so, in the words of Lord Simon in McGhee, made a substantial contribution to the condition from which they suffer. If the respondents should, as in our view they should, have changed their practices this would have reduced the risk that the appellants’ condition ceased to be asymptomatic and began to show symptoms. As Mr Cooksley points out, it is relevant to look at the point at their working lives when they began to experience symptoms. 1992 and 1995/1996 are not many years removed from when the works at Llanwern closed. It is possible that with improved working practices the appellants would have remained completely symptom free throughout their time at Llanwern. Alternatively, the symptoms could have arisen later than they did and have been of less severity.
49.	We conclude, in the words of Hale L.J Transco v Griggs, that it would be an unjust legal system which did not on the evidence advanced on behalf of the appellants and the concessions made by the respondents, hold the respondents responsible for what happened to these three appellants. The respondents did not call evidence to attempt to displace the inference of causation which the McGhee principle supports in their cases.
50.	Although the appeal was not advanced on this basis, it seems to us at the very least arguable that the judge could have found, just as was Lord Kilbrandon’s view in McGhee, that the appellants’ condition was on balance of probabilities directly caused by the respondents’ breach of duty. A robust approach of this nature might have rendered unnecessary a careful analysis of McGhee and Fairchild which, as it happens, leads to the same result.
Training 
51.	The judge observed that BS 6842 included guidance that there should be adequate training to instruct the workers in the proper use of the equipment. He found that the appropriate level of training and information varied over time as knowledge and understanding improved and that some information concerning HAVS and some training in the use of tools should have been available by March 1977. The training with which the respondents should have been provided was e.g. in how to use the machines with a loose grip etc. But the judge went on to say that there was no evidence as to the effect, if any, any such training might have had. There was no evidence as to what the training would have comprised or how it might have been effective in reducing the vibration dose of any employee. Indeed there was no evidence upon which he could conclude that had the respondents complied with their training obligation the vibration dose of any employee would have been reduced.
52.	In our judgment this finding cannot be sustained. As the judge had made clear earlier in his judgment, the vibration level experienced by the operator of a machine depended on several variables including the type of material being worked on, the operator’s grip on the machine and the nature of the machine itself. From as early as DD43 in 1975 the message was being conveyed to the respondents in the literature that working methods were relevant to reducing the incidence of vibration injury. By 1994 the Health and Safety Executive was issuing guidance in the form of HSG88 setting out a series of measures to reduce the vibration energy directed into a worker’s hands. These included:
•	Substituting a process involving less vibration e.g. replacing hammer swaging with roller pointing.
•	Using tools designed for low vibration e.g. tools with vibration isolating handles.
•	Correct routine maintenance of tools.
•	Arrangements to reduce the grip, push and other forces.
•	Using tools designed to avoid the need for workers to grip high vibration parts. 
•	Training workers in operating techniques.
•	Avoiding uninterrupted vibration exposure over long periods.
•	Proper selection of tools for the task.

53.	Also, advice should have been available about wearing gloves and maintaining circulation in the fingers. As the judge said, some training should have been provided from 1977. Whilst one would not have expected its level and extent to have been the same in 1977 as in the 1990s, it should have improved over time with knowledge and experience. It seems to us clear that had the appellants been appropriately trained over the years their exposure levels would to some extent have been reduced.
54.	We appreciate there is some overlap between on the one hand taking steps to reduce vibration levels and on the other appropriate training of employees, and that several of the matters in the 1994 guidance could be said to fall under the former category rather than the latter. However the fact is that the respondents neither took steps to reduce the level of vibration exposure nor give the appellants adequate training.
55.	In our judgment the judge’s finding on the effect of training runs into the same difficulty as his finding of the effect of reducing vibration levels. In each instance he was wrong to conclude that the causative link was not established. The court did not have to know the precise reduction in exposure that would have been brought about. It is enough that there would have been some reduction, which in our judgment, on the evidence, there plainly would have been, and this would have reduced the risk of injury to the appellants. Again the McGhee test applies.
Warnings and medical surveillance 
56.	The judge said the issue was the effect that the warnings, information concerning HAVS, monitoring and medical surveillance, which he had found the respondents were under a duty to supply, would have had on the appellants.
57.	The judge held that the respondents ought to have introduced a system of medical surveillance. There was a duty positively to monitor employees at risk and seek out symptoms. Also, they should have warned employees of the risks of contracting HAVS as a result of using vibrating tools. He referred to the type of warning as similar to that mentioned by Judge L.J in Armstrong (p.23).
58.	The judge, as we have already mentioned in para 15, describes the difficulty of deciding what a particular claimant would have done if the respondents had warned and medically monitored him.
59.	He went on to point out that as a matter of practical reality most employees would regard the possibility of HAVS as less than serious unless and until the first systems appeared. He went on to consider the case of each appellant separately. As to Brown, he said that despite his evidence to the contrary he was not satisfied that he would have sought and obtained alternative employment. He concluded that proper monitoring and medical surveillance would probably have elicited Brown’s symptoms within three years of their first arising (on the basis of a three year interval between examinations). He first noticed symptoms in 1996. He continued to work and never sought clinical intervention. He first saw the appellants’ expert in 1997. 
60.	As to Grogan, he did not accept his evidence that if he was warned and told about HAVS he would have looked for another job. He said Grogan had a young family and moved to the refractory department because the pay was better than in the civil engineering department and overtime was more readily available. He did not seek an easier job after he started suffering from symptoms in his hands in 1992 or even when he began to associate his symptoms with the use of vibrating tools in 1995. He said:
“Whilst the decision is not easy, I am not satisfied that Mr Grogan, if properly warned, would have changed his job. In all of the circumstances, I find that he would have continued to have worked until he began suffering from symptoms. 
He began suffering symptoms in his hands in 1992. He thought they were just old age. Had he been warned, or provided better information about HAVS, or been the subject of medical surveillance, he would probably have realised that these symptoms were of HAVS earlier – probably as early as 1992. Would that have changed the course of his employment?
Again, the decision is not easy, but I do not think it would have done. Mr Grogan suspected that the symptoms in his hands were caused by his use of vibratory tools at work at 1995. Then there is no evidence that he took any steps to change jobs, or seek work elsewhere. Dr Grayson attributed the symptoms to vibrating tools in his report of 3 May 1997. If he did not know before, in that report, he was told that, if he continued with his use of the tools, his hands could get worse. However, he continued in his job. The symptoms did not prevent him from working, nor did they prompt him to seek medical intervention. Circumstances for Mr Grogan (in terms of age and prospects for alternative work) were not so very different in 1992 than 1995 or 1997.
In all of the circumstances, I find that, had Mr Grogan known that he had the first symptoms of HAVS in 1992 (rather than 1995 or 1997), his actions (and the course of the condition) would not have changed.”
61.	As to Trickey, the judge says he worked at Llanwern for over thirty years without suffering any symptoms despite the high level of vibration to which his hands were exposed. If he had been told that if he continued working he could suffer tingling and numbness he would have expected him to continue unless and until symptoms appeared. Within months of noticing symptoms he was aware they were associated with his use of machines, but there is no evidence he even considered alternative employment. The judge concluded:
“If he had been warned and medically monitored, so that he was aware that the symptoms were caused by his use of vibrating tools as soon as the symptoms arose (1995, instead of 1996 when he did appreciate the connection), I do not consider that that would have affected any of his actions or his work pattern or his exposure to vibration.”
62.	The judge concluded that in each of the three cases warnings and medical surveillance would have made no difference. Accordingly, breaches of duty in this regard were not causally linked to the appellant’s condition.
63.	Permission to appeal was not given on this point. Tuckey L.J said that judge had made clear findings of fact and there was no real prospect of the court of appeal interfering. Mr Cooksley accepts that the judge’s findings of fact about the appellants are unassailable, but submits that is not the end of the matter because one has to go on to consider the further response of the respondents once there were symptoms. He seeks to shift the emphasis away from the employees to the employers. He contends the judge failed properly to consider the duty on the respondents to remove the appellants from the use of dangerous tools had the appellants reported symptoms following a warning or had symptoms been picked up through medical surveillance. 
64.	It seems to us that the appellants are now trying to advance this issue in an entirely different way from, that in which it was put before Judge Hickinbottom. The short answer is that the judge made a clear finding of fact that resulted in each appellant’s case failing on causation on this point. We are not persuaded that there is any justification for granting permission to appeal and thereby open up an issue that was not explored below.
Conclusion
65.	In our judgment the appellants should have succeeded in the following respects:
i)	The judge should have found the respondents were under a duty to reduce the levels of vibration to which the appellants were exposed.
ii)	The judge should also have found that in so failing and in failing to comply with their training obligations the respondents materially increased the risk of the appellants contracting HAVS. 
66.	Accordingly the judge should have found in favour of the appellants on liability and we therefore allow the appeals and remit the claims to the Cardiff County Court for damages to be assessed.