HKSAR v. Ken on Concrete Co. Ltd.

HCMA001304/2000

HCMA 1304/2000

IN THE HIGH COURT OF THE

HONG KONG SPECIAL ADMINISTRATIVE REGION

COURT OF FIRST INSTANCE

MAGISTRACY APPEAL NO. HCMA 1304/2000

(On appeal from of KTS 4330/2000)

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Coram: Deputy High Court Judge Barnes in Court

Date of Hearing: 3 May 2001

Date of Judgment: 10 May 2001

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JUDGMENT

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Introduction

1. On 17th November 2000 at the Kwun Tong Magistracy, the appellant company ("appellant") was convicted after trial on an information that being the proprietor of an industrial undertaking, it failed to provide and maintain concrete mixer and system of work in connection with concrete mixer cleaning work that was so far as reasonably practicable, safe and without risks to the health of all persons employed, contrary to sections 6A(2)(a) and 6A(3) of the Factories and Industrial Undertakings Ordinance ("the said Ordinance"), Cap. 59, Laws of Hong Kong. The appellant was fined $20,000.

2. It now appeals against the conviction.

Brief Facts

3. It was not in dispute that the appellant was the proprietor of an industrial undertaking, namely, Tseung Kwan O Plant where concrete mixer cleaning work was in progress on 5.10.1999 when a fatal accident occurred, involving one Fung Yue-don ("the deceased"), an employee of the appellant. The accident happened after the concrete production work had finished. The deceased, who was a cleaning worker, was found lying unconscious inside one of the two concrete mixers ("the mixer") operated by the appellant. There was also no dispute that the mixer was under the control of the appellant.

4. The mixer had two sets of hatches on top. Each set had two doors interlocking each other when closed. There was a control room some distance from the mixer where an operator operated a control panel. The mixer was cleaned daily by washing with a hose and often required hammering away of hardened concrete. A cleaner was required to climb inside the mixer to do the cleaning. Each night at about the time of cleaning a truck would arrive to collect the waste water. Upon the truck's arrival, the operator would press a button on the control panel (sometimes referred to as the "HH button") to electrically cause a scoop or tube attached to the mixer to position over the lorry for the discharge of the waste water.

5. The mixer had the following features:

1. A mains power switchboard with an on/off key which was located on the wall in the control room;

2. A control panel in the control room with on/off switches;

3. An emergency stop switch outside the control room near the mixer, which could only be reset with a key once activated; and

4. Two micro-switches, one for each set of hatches. When the hatches were closed one door of which would then press down a plunger, which then activated the mixer. When the hatches were opened, the electricity supply to the mixer would be cut off, stopping it from operating.

6. For the mixer to operate, the mains power had to be "on", the controller had to switch on the button at the control panel after the hatches of the mixer had been closed, and the emergency switch had to be "off". The design was such that if the hatches were not closed the mixer would not operate. Or, if the emergency switch was activated the mixer would not operate even if the hatches were closed.

7. The prosecution case was that on the night in question, the truck was late and the controller (PW3) instructed the deceased to hose the mixer first. The deceased had gone inside the mixer to do the cleaning. PW3 did not turn off the mains power as he was waiting to position the scoop over the truck upon its arrival. When the truck arrived, instead of pressing the HH button to release the scoop, he accidentally pressed the button on the control panel and set the mixer in operation.

8. Examination of the mixer after the accident by PW10 showed that one of the two micro-switches was defective, allowing the mixer to operate when one set of hatches was not closed. PW10 was of the view that the defect was not a sudden one. Such defect was not visible to visual inspection but a trial-run would have detected it. He recommended regular trial-runs as a safety measure.

9. The appellant called an expert (DW2) on the safe system of work. With the assistance of exhibit D2, a 'Fault Tree Analysis of factors leading to the accident', he illustrated how the mixer could have operated with a worker inside. He was of the view that the defect found on the micro-switch was a sudden one and the accident a freak occurrence. He opined that it was not reasonably practicable to conduct regular trial-runs as suggested by PW10. He was of the view that the maintenance schedule and the practice adopted by the appellant was a reasonable one, bearing in mind there were inspections, maintenance, safety talks, code of practice etc. His view was that the appellant had done what was reasonably practicable at the time of the accident.

10. The Learned Magistrate found the appellant guilty as charged.

Grounds of Appeal

11. Mr. Osmond Lam, counsel for the appellant, advanced five grounds of appeal which ran to some 9 pages. I do not intend to reproduce the grounds here. Suffice it to say that there are two main areas of attack:

1. The conviction is unsafe and unsatisfactory as the Learned Magistrate had made important findings of facts which were not supported by the evidence; and

2. The appellant had done everything reasonably practicable and that it had discharged the statutory duties based on its knowledge of what was reasonably foreseeable prior to the accident.

12. I will first deal with the submission that the learned magistrate had made findings not supported by evidence.

Defect of one micro-switch

13. PW10's evidence that one of the micro-switches was found to be defective after testing done within 12 hours of the accident was not challenged. Nor was his evidence that the defect was a hidden one, not visible to visual inspection challenged. Mr. Lam took issue with the Learned Magistrate's following findings:

".... I accept his evidence that one of the micro-switches examined by him had failed because the wires had been screwed into place too tightly and this had caused distortion of the switching mechanism inside the switch. ...........I further found from PW10's evidence that the fault had been in place for some time and I was satisfied beyond reasonable doubt that the switch had not entered into this state of fault due to its use. I found the only inference, and this was irresistible, was that it had been caused at the time of the installation of the wires into the switch."

14. Mr. Lam submitted that it was wrong for the Learned Magistrate to find as a fact that the cause of the failure of the micro-switch was "because the wires had been screwed into place too tightly and this had caused distortion of the switching mechanism inside the switch" when PW10 himself did not go as far, merely saying that it was a suspicion.

15. Mr. Lam also relied on the evidence of PW6, who had installed and tested the 'new' micro switch on 3rd September 1999, and the evidence of DW1 to the effect that a proper test was done at time of installation, to support his argument that the switch could not have been faulty at the time of installation. He further relied on the fact that both mixers were in operation on the day of accident and on the evidence of DW2 to say that the fault was a sudden or freak occurrence. He submitted that the appellant should be given the benefit of the doubt when both explanations were possible.

16. PW10's evidence was that the test showed that before the wire was disconnected, the switch was stuck. However, after the wire was disconnected the switch was back to normal. He then said (at page 106 of the transcript):

"..So, I suspect that - it's just a suspicion, right, I do not go further to prove - I suspect that it is because when you terminate the wires to the cable terminal...when you connect the wires to the cable terminal and when you tighten the screw, you exert strain on the switch mechanism. It might be possible - it might be possible only - because of the strain, you twist the gear, so it got stuck. But I do not want to go further but my remark was I would believe that, by the wires were terminated to the switch, the defect would exist. That means, by the time you terminate it, the defect was there. It did not come in a sudden, I would believe so. That is, if you terminate it three months ago, and then it is defective since three months before. It's not a sudden defect." (Emphasis added)

17. It is clear from PW10's evidence that he only suspected the tightening of the wires being the cause of the defect. He did not know what was the cause of the defect (see page 112 of the transcript) and he did not actually see any 'twisting' of wires when he opened the box (page 110 of the transcript).

18. The learned magistrate has erred in accepting that part of PW10's evidence as fact when PW10 was merely stating his suspicion. However, the cause of the defect, though important, was not the only factor to be considered. In issue was whether the defect was a sudden one and whether routine trial-runs would have detected it. Bearing in mind the evidence of PW10 that the test showed the switch was stuck before the wire was disconnected, and that it was back to normal after the wire was disconnected; and the evidence I have quoted, particularly those underlined, it is clear that while PW10 suspected the tightening of wires caused the defect, he believed the defect was present at the time when the wires were connected to the cable terminal, i.e. time of installation. Though the learned magistrate had wrongly accepted PW10's suspicion regarding the cause of defect as evidence, he was entitled on the evidence before him to find as a fact that the defect was not a sudden one, and to draw the inference that such defect existed at the time of installation based on PW10's evidence. He was also entitled to disbelieve the evidence of PW6 and DW1 that a proper test was done upon installation.

Concrete hardening causing one of the hatch doors to jam

19. Evidence adduced showed that during the examination after the accident, one of the four doors to the hatches was found not able to close. The micro-switch attached to this particular hatch was found to be in working order. The learned magistrate found (paragraph 19 of the Statement of Findings, p. 19 of the Appeal Bundle) it an irresistible inference that concrete had hardened on the door after the hatch had been opened in the emergency evacuation of the deceased.

20. Mr. Lam complained that there was no evidence before the court for the learned magistrate to draw such an inference, in particular, PW10 had never said that the door was jammed because of the presence of hardened concrete.

21. There was certainly evidence to the effect that concrete did harden inside the mixer, thus the need to 'hammer' the concrete away when cleaning. PW10, when questioned by the learned magistrate on the issue of 'jammed door', said (at p. 113 of the transcript):

"A. Something jammed or, may be - I do not surprise because it is concrete plant. Even you have a small sand or small bit of concrete stay on the rim of the mixer and then you can't close the door tight. It is foreseeable. I should say."

22. DW2, who was accepted by the learned magistrate as an expert on mixers (paragraph 13 of the Statement of Findings, page 13 of the Appeal Bundle) said in evidence (page 162 of the transcript):

" Q. Can you, from your experience, give any explanation about that door not being able to shut?

A. It could have been a number of reasons. Most probably it was because of the concrete that were - have been splashed on the rim of that hatch jamming the door...preventing a full closure."

23. It should be noted that DW2 also said it would have usually taken some time for the concrete to build up (p.163 of the transcript).

24. There was clear evidence before the learned magistrate that the mixer had been used prior to the accident. Although PW10 said that the mixer should not have operated with one of the doors jammed, PW10 could not give evidence as to whether the door was jammed prior to or at the time of the accident. The learned magistrate was entitled to find that the mixer could not have worked if that door had not been shut properly based on the evidence of PW10 that the micro-switch attached to this hatch was in working order when examined after the accident. He was entitled on the evidence before him to draw an inference that it was hardened concrete that had caused the door to jam after the emergency evacuation, though I must agree such inference was not an irresistible one. In my view, it was not necessary for the Learned Magistrate to state a reason why the door was jammed when examination took place. He was entitled on the evidence before him to find that the door was jammed after the accident.

Micro-switches known to fail regularly

25. Mr. Lam complained that there was no evidence to support the Learned Magistrate's findings that the micro-switches failed regularly. DW1, when questioned by the Learned Magistrate, said (at page 141):

"How many times in one year would you replace the switches on this concrete mixer, the microswitches?

A. It will be changed once every four months.

Q. What, as a matter of routine or because once in four months they go wrong?

A. No, it will be changed only when we find that it is too old or it has been worn out and we are doing the maintenance work or colleagues reported to us that it has to be changed.

Q. So, these switches have a life expectancy of about four months and often shorter than that?

A. The life expectancy of the switch is longer than that but the problem is that it is very dirty with a lot of concrete attached on it."

26. The Learned Magistrate appears to have used the words "failed regularly" to describe the need for replacements. Replacing switches at intervals of 4 months could fairly be described as a regular occurrence.

Time-span required for the trial-run

27. The relevant findings on this issue could be found in paragraph 13 of the Statement of Findings (page 15 of the bundle):

"I reject DW2's evidence that it was a cumbersome procedure to do a manual checking of the whole system for the mixer, as it was suggested the check would take as long as one hour to complete. I found that the test would not in fact take as long as that and could be done in much less time".

28. PW10's evidence on the time needed for the test could be found on page 104 of the transcript:

"A. If just the trial run itself, it doesn't take long, I think within an hour. I could not tell the exact time but it's not long - not take long time. It's not difficult. You do not need special machine or so."

29. DW2 was cross-examined on the time needed to do the testing. Miss Lee for the prosecution put to DW2 that the test needed about 30 minutes to do. DW2 disagreed and said that if the appellant had to run all other equipment in a batching plant, it could probably take a few days (see p.156 of the transcript).

30. It is unclear why the Learned Magistrate said that DW2 suggested it would take 'as long as one hour' to complete. How Miss Lee came to suggest the time needed was about 30 minutes when there was no such evidence is also a mystery. Judging from the tenor of PW10's evidence, his evidence was that the test would not take long to conduct. Nevertheless, there was no evidence to support the Learned Magistrate's finding that the actual test would take much less than an hour to conduct. For reasons I will further elaborate when I consider the issue of safe system of work, this erroneous finding does not render the conviction unsafe and unsatisfactory.

31. I will now turn to the second area of attack.

Was PW10 called as an expert?

32. Mr. Lam submitted that PW10 was called to give factual evidence of the examination of the mixer after the accident, not as an expert to give opinions. DW2, he submitted, was an expert on the safe system and the only witness in the trial. The Learned Magistrate should have dismissed PW10's opinion and accept DW2's evidence.

33. While it is true that the prosecution's attempt to call PW11 (Cheng Foon) and PW12 (Lee Wai-tong) as expert witnesses were objected to by the defence and the Learned Magistrate ruled after hearing submissions that these two were not experts. In the case of PW10, it is incorrect to say that he was proffered by the prosecution as a factual witness only. The relevant transcript is at page 95:

"COURT: This man's an expert, is it?

MISS LEE: Actually, I want to-yes, establish his evidence on the expert area about the maintenance of the switches.

MR. LAM: Sir, he's a - I don't know. I think he's a electrical engineer. I don't know if he's an expert on the maintenance. I am not query about his qualification as a electrical engineer.

COURT: Yes, well. Let's see what comes out."

34. It can be seen that the prosecution was not calling PW10 as a factual witness only. He was called as an expert on the maintenance of switches. After the academic qualification and work experience of PW10 had been established, PW10 proceeded to give evidence, both on the factual issue of the actual examination and opinion concerning the system of electrical safeguard, in particular the micro-switch. He was extensively cross-examined by Mr. Lam, who also represented the appellant during the trial. When PW10 finished his evidence, the Learned Magistrate discussed with counsel regarding when the next witness could be called. At no stage after the initial query did Mr. Lam raise any query on PW10's expertise again, nor was the Learned Magistrate asked to make any ruling during the trial.

35. The Learned Magistrate accepted PW10 as a man with electrical expertise and found DW2 not to be an expert on electrical matters as DW2 had no electrical qualifications. The Learned Magistrate was entitled to make such findings based on the evidence before him. He was therefore entitled to rely on PW10's expert opinion on the maintenance of the micro-switch, and to reject DW2's opinion on any matter electrical, though DW2 was accepted as an expert on mixers. On this basis, although DW2 testified that regular trial-runs were too cumbersome, and the Learned Magistrate had erroneously found that the time needed was much less than an hour, there was clear evidence from PW10 that the trial-run would not take long and should be carried out on a regular basis. On the evidence before him, the learned magistrate was entitled to reject DW2's opinion and found that the regular trial-runs should have been carried out. I do not find this erroneous finding of fact by the learned magistrate render the conviction unsafe and unsatisfactory.

micro-switches only one mechanical part of the system

36. Mr. Lam submitted that when considering this matter in hindsight, one should bear in mind that cleaning process was a matter of regular routine and was carried out with a minimum of fuss every night. The workers were all experienced and knew what the procedure entailed. The cleaners all knew that they should turn the emergency switch on before entering the mixer. He complained that the cleaning process was placed under microscopic examination at the trial. Mr. Lam said that by focusing on the defect of the micro-switch, one of the components of the whole system, and ignoring that there were regular inspections, maintenance, code of practice, safety talks and supervision, the Learned Magistrate wrongly employed insight and knowledge gained from hindsight in determining what should and should not have been done prior to the accident.

37. Mr. Lam relied on following passage in the judgment of Jackson J. in HKSAR v LEIGHTON CONTRACTORS (ASIA) LIMITED, HCMA 1029/2000, at page 11 to support his argument:

"It seems to me that the evidence of the expert witness for the prosecution upon which the Learned Magistrate appears to have placed great reliance was little more than an expression of ideals and a counsel of perfection arrived at in hindsight in an attempt to explain what, on the face of it , was inexplicable."

38. The Learned Magistrate found that there was a system of maintenance but it was cursory. He accepted DW1's evidence that only visual checks were carried out and that switches would mainly be changed upon report of faults. He found such maintenance system insufficient for the micro-switches and emergency switch as they were switches of crucial importance to any men working in the mixer.

39. The Learned Magistrate found that the training and supervision were lacking in the operation. He found that there was a lack of clear instructions to the controller as to what to do when the lorry arrived since he (the operator) instructed the deceased to go inside to hose the mixer when the mains power was on. The operator had also failed to test the control penal button even though such a procedure was required in the code of practice.

40. The Learned Magistrate also found that the appellant had failed to satisfy, on a balance of probabilities, that it was not necessary, not practicable or not reasonably practicable to do more than was in fact done to satisfy the duty or requirement, or that it had taken all reasonable steps, or practical steps or done the appropriate thing to satisfy the duty or requirement under section 18 of the said Ordinance.

41. I have already ruled that the Learned Magistrate was entitled to accept the evidence of PW10 on matters electrical. His finding that the appellant's maintenance system was insufficient was supported by evidence and could not be faulted.

42. The Learned Magistrate had carefully examined the evidence of the employees of the appellant and came to the conclusion that there was no clear defined process of training and supervision of the operation. He was entitled to come to that view on the evidence before him. His comment on the fact that 'the code of practice notice was covered in cement' being 'indicative of the attention that was given to its importance' (paragraph 17 of the Statement of Findings, page 19 of the bundle) was a perfectly logical and reasonable one. The cleaning process might have been routine, a cleaning process involving a person to climb inside the mixer, with the foreseeable inherent danger to life and limb, was such that extra caution and precaution need to be exercised.

43. The feature of the micro-switches was indeed one of the components of the whole system. However, where human errors could occur, (as in the case of the mains power being left on, the emergency switch not being turned on, and/or the HH button being pressed by mistake), the micro-switches acted as a last resort (as described by DW2 on page 164 of the transcript) to ensure safety. The Learned Magistrate cannot be faulted in emphasizing the importance of the maintenance of these switches where a person's life and limb were at stake.

44. The Learned Magistrate was correct to take into account that experienced workers could become complacent and it was the duty of the employer to ensure their safety. In this regard, supervision, even for cleaning work, would have ensured that workers did not take short cuts.

45. On the evidence before the Learned Magistrate, he was entitled to find that the appellant had failed to provide or maintain the mixer and a system of work in connection with the mixer cleaning work that was so far as reasonably practicable, safe and without risks to the health of all persons employed. Further, on the evidence before him and upon his findings, the Learned Magistrate was entitled to come to the conclusion that the appellant had failed to discharge the onus of proof under section 18 of the said Ordinance.

46. The Learned Magistrate was aware that he should not seek to impose upon the defendant " a counsel of perfection". He adopted 'as the measuring criteria a reasonably expectable system of maintenance and work which was reasonably obtainable and within reasonably practical limits.' The Learned Magistrate did not use knowledge and/or insight gained from hindsight to impose on the appellant a higher standard than required.

Conclusion

47. For the reasons given, the conviction is neither unsafe nor unsatisfactory. The appeal is dismissed.

Representation:

Mr. Joseph Wong, SGC for the HKSAR Respondent

Mr. Osmond Lam, instructed by Messr. Mallesons Stephen Jaques for the Appellant