Running Webinars

Last year I started running teletutorials for a Distance Learning Masters course in Occupational Hygiene. The students were spread out across the globe, so it's not practical to get them together in any other way. I soon found that trying to run them over the telephone was hard work, so decided to try supporting the discussions with software that allowed me, and the participants, to show Powerpoint presentations and other documents on screen as we talked. Effectively, I'd turned the telephone tutorials into webinars.

This has been a new experience for me, and I've very much had to learn as I've gone along. So it was interesting to view a short introductory webinar on:

3 Things Every Presenter Should Know about Webinars | myBrainshark.

presented by Roger Courville, the author of the Virtual Presenter's Handbook.

The key points for me were

• Adapt to the medium - i.e. don't treat the webinar the same as a face to face seminar


• Engage the participants early and often


• Break up the presentation - use polls, Q &As and discussion

Actually, I think the 2nd and 3rd points are pretty valid for face to face seminars too. Certianly I try to keep the group involved whenever I run one. So in reality good practice for both types of session is very similar.

The joys of LEV testing - Part 1

Quite often when testing a local ventilation system it isn't possible to access the hoods when the process is operating due to safety considerations. Many woodworking processes fall into this category, but there are plenty of other situations where this is the case. It's only possible to measure face and capture velocities when the process isn't running and as the process itself will affect the airflow, measurements taken when the process is down are not representative.

In such cases it's often best to measure the static pressure behind the hoods (in a location that can be accessed safely) but the results are only meaningful where there is data from an initial evaluation obtained when the system is performing as intended and when it is known that control is being achieved. You also need to know what variance in pressure is acceptable (i.e. at what pressure the system stops being effective). Of course, most companies do not have such data!!

Information overload in presentations

At the conference on REACH I attended a few weeks ago, as usual, all the speakers used slides crammed with information – far too much to cover in the short time slots they were allocated. In every case they either moved through the slides too quickly (so the audience didn’t have time to finish reading the individual slides) or ended up skipping and missing a number of slides.

Why do they do this?

I think that one of the reasons is that speakers at conferences usually have a limited time slot, but have a lot of information they want to communicate. By cramming information onto slides you reduce the total number and fool yourself into thinking that the amount of material you are trying to get across is manageable in the time available. It’s a little like burying your head in the sand. The problem of too much material disappears – until you try to present it!

Most presenters at conferences I’ve attended don’t seem to put thought into the design of their slides. Typically they default to using the easy option of using the standard Powerpoint template which encourages the use of bullet points and sub bullets.

Slides should support the presentation – they’re not a substitute for it. However, where they are used they need to be well designed if they are to perform their function effectively. I think that most presenters don’t put too much thought into that aspect of their presentation. They tend to default to using the standard Powerpoint template that focuses on using words, structured as bullets and sub-bullets.

Research has shown that its better to minimise the number of words on a slide and to use pictures or other visuals where possible. I don’t intend to go into it here, but there is a good explanation of the theory in a recent post on Olivia’s Mitchell’s blog “Speaking about Presentation” which includes a summary of some recent work by Chris Atherton, a cognitive psychologist from the University of Central Lancashire.

Some good advice on slide design is available also available in a number of books such as Beyond Bullet Points by Cliff Atkinson, Presentation Zen by Garr Reynolds and Slideology by Nancy Duarte.

BOHS Examination changes

A few weeks ago BOHS announced that from November the 1st all module examinations will have a new format.

The exam will still be in two parts but from 1st November

• Part A will consist of 40 short answer questions rather than 60 multiple choice questions. There are pros and cons for candidates, but the biggest advantage is that there will no longer be any negative marking.
• Part B will changed so that candidates will be required to answer 5 "micro-essay" questions from a choice of 8.
• The pass mark will remain at 50%

Personally I think the change to part A will be beneficial. As there is no negative marking it will be advisable to try to answer all the questions. Currently some candidates hesitate on some questions where they are not 100% confident, even though they may know the answer. And it will only be necessary to get 20 out of 40 right. Another benefit is that as each question is worth 4 marks, some answers may gain partial marks. This will be particularly helpful with calculation questions where marks can be gained providing an appropriate method is used even if the final answer is incorrect due to a slip in the calculation (working will need to be shown to ensure this happens). Currently a small slip results in a negative mark for an incorrect answer even where the candidate understands the principles involved.

For Part B, instead of one long question from a choice of two, candidates will be required to answer 5 out of 8 "micro-essay" questions. BOHS have now released some example questions which can be accessed here.

Given the time available for the exam hasn't changed (2 hours 15 minutes total) with 45 minutes meant to be devoted to Part B, they are expecting no more than 15 minutes to be devoted to answering each of these "micro-essay" questions, so candidates answers will need to be concise, while ensuring that the key points are included. Experience will show how easy it is to achieve this.

Slideology Webinar

Yesterday I participated in a webinar held by Nancy Duarte of Duarte Design, the author of “Slideology“. I’m a big fan of her book and her approach to presentation design so was keen to listen to what she had to say. I had some computer problems so missed the first twenty or so minutes of the 60 minute session, but it was still worthwhile logging in.

The points made by Nancy really covered the same ground as her book, but it was good to hear them presented “in person”, so to speak. I also found it interesting to look at the slides she’d designed for her presentation. The key points that I took away from the session were:

• when preparing for a presentation, stand back from the computer. Presentation design programs like Powerpoint can lead the user and limit their imagination. The brain isn’t digital and its good to use old fashioned tools like paper, note cards and sticky notes to brainstorm and arrange ideas
• Don’t try to cram too much on one slide. “Slides are free”. Split ideas over many slides rather than cramming them all on to one.
• A good slide designer needs to be a communicator, a graphic analyst and a draughtsman!
• Deliver a profound experience to the audience – a “STAR” moment (Something They’ll Always Remember)

Safari Books will be posting a recording of the webinar on the net in the next day or two. I don’t know whether it will be generally available but as I participant I’ll be downloading it and watching the presentation again.

Conferences ae always a "mixed bag" and this was the case with the REACH meeting held in Brussels on 30 September/1 October. Overall, it was worthwhile attending and I certainly learned more about the requirements of REACH relating to occupational exposures were being implemented in practice. Some of he contributions wee a little too basic, given the nature of the conference and the audience, but the majority were useful.

The key points I took away from the conference were:

• there remains a clear conflict between the requirements of REACH and occupational health and safety legislation. The objectives are the same (i.e. protecting the health of workers and others) but there are significant differences in their approaches which could potentially lead to conflicting perceptions of risk and requirements for control.
• insufficient thought was given to how the REACH requirements on hazard and exposure assessment could be applied in practice before the legislation was introduced. Companies implementing the requirements are having to develop the methodologies as they go along and the timescales are too tight to allow then to be properly validated before deadlines have to be met.
  
• REACH DNELs(derived no effect levels) are consistently tighter than Occupational Exposure Limits (OELs) due to the major differences in the ways they are established. This can lead to confusion and as DNELs are used in the risk assessment process to develop "risk management measures" (RMMs) it is highly likely that the REACH process will result in tighter controls being specified than those based on a risk assessment using established OELs. Although this problem has been known about for a number of years, it has still not been resolved.
• The tools needed for exposure assessment, which is required to allow RMMs to be specified, are still not fully developed and validated.
• the Advanced Reach Tool (ART) looks promising and may have wider occupational hygiene applications, but needs to be validated.
• there are a number of "first tier" exposure assessment tools (i.e. basic exposure modelling methods). A number were described during the conference. It would have been useful to see them demonstrated, using the different tools for the same substance so that their conclusions could be compared.
• modelling techniques are always going to have their limitations, and this is particularly true for the basic "first tier" models. They need to be used by people who understand exposure assessment and these limitations. Ideally they shoul only be used as part of the exposure assessment process. There is a real danger that this won't happen in many cases and that RMMS will end up being specified by inexpeienced people using only the flawed, basic models. From what I saw at the conference the models tend to err "on the side of safety" (just like COSHH Essentials). This may mean that worker health won't be adversely affected but it could have economic consequences for he employers and possibly damage employment.
  

The occupational hygiene community has the expertise to develop the methodologies, and also has the knowledge and experience to work out how the REACH process could be improved. Unfortunately, I doubt that we have sufficient "clout" to influence the powers that be on this and we are going to have to live with, and try to manage, the consequences once the Regulations start to impact on "downstream users".

REACH - Registration and beyond

Tomorrow I'll be heading off to Brussels for the meeting on REACH (REACH: Registration and Beyond: Exposure Scenarios and safe handling advice) organised jointly by BOHS and their Dutch sister organisation, NVVA.

The conference focuses on some important issues , including exposure assessment. REACH requires manufacturers and importers of substances and mixtures to develop exposure scenarios and appropriate risk management measures. This is a major requirement which, with the current methodologies available for assessing occupational, environmental and consumer exposures, would be impossible to achieve. Consequently a lot of work is going into developing exposure models and guidance for exposure assessment which manufacturers and importers will be able to use when the target dates for the exposure scenarios approaches.

I'm hoping that the conference will help to bring me up to date on what progress has been made. There are so many factors that affect exposures in the workplace, so it will be interesting to see how far these have been incorporated into the models being developed. Its a big ask.

Stack heights

When designing and testing local exhaust ventilation systems we need to pay particular attention to the design of the extraction hoods - where the contaminant enters the system. If this isn't right then the system is unlikely to be effective at controlling contaminants. However, this doesn't mean that we shouldn't ensure that other aspects of the system are properly designed.

In many cases the system will exhaust outdoors and its then important to ensure that any contaminants remaining in the airstream are dispersed effectively so that they do not re-enter the building. This means that they shouldn't be located too close to any air intakes, vents or windows. It is also particularly important that the stack is high enough. A good "rule of thumb" to follow is that the stack should be at leas one third the height of the building (i.e. it should release at a height 1.33 times the building height). The stacks on the laboratory building shown in the picture above meet this criterion. There are plenty of others out there that don't! Here's a few.

Terminolgy

When you've been working in a particular profession for a while its easy to forget how confusing terminology can be. I find that although we take for granted what is meant by "local" and "general" ventilation, the meaning is not necessarily obvious to someone new to occupational hygiene or to non-specialists, such as managers and workers in industry.

"Local exhaust ventilation" is used to describe extraction systems that extract contaminants close to the source, thereby preventing dispersion into the workplace. Yet although most people would probably interpret "local" as meaning "close to", I don't think that "local ventilation" is necessarily understood to mean that capture occurs at source. I've seen lots of poorly designed systems, including fans located in walls a fair distance from the source classed as "local extraction". Similarly the term "general ventilation" is rather vague and I'm not convinced that most people understand what we mean by this - i.e. the use of extraction to dilute contaminants in the ambient workplace air.

There are also some situations where the terminology breaks down. For example, in a walk in spray booth contaminated air is extracted from the whole room, not from near the source. The worker inside the booth is not fully protected as he/she is still located within the contaminant cloud. From his / her perspective this is not local extraction. Yet, at the same time, it is something more than what we would normally class as "general ventilation".

To overcome these problems, perhaps the use of alternative terms such as source ventilation, room ventilation and dilution ventilation would be better.

Plants aren't always good for you!

I spotted this article in the New Scientist.

I've often come across the view that using plants is a good way of dealing with pollutants in the indoor environment (see my previous post here). Although there is some merit in this, it isn't always true that plants are beneficial and the research findings described in the New Scientist article shows how plants can actually increase pollution.

All living organisms process, produce and emit chemicals. Sometimes these are beneficial and sometimes they are harmful. Just because something is "natural" doesn't mean that it is harmless. Botulinum toxin is a "natural" chemical - and its extremely toxic.

Occuaptional Hygiene in developing economies

I found this presentation on Slideshare

Although I'm not so complacent to think that control of asbestos is perfect here in the UK, I think it would be unlikely to find anything quite as blatant as the situation shown on these slides.

I guess that this example illustrates the difference in standards between "developed" and "developing" economies. Some commentators argue that the health, safety standards required by legislation are driving work away from Western Europe and the US to countries such as Turkey, Eastern Europe, India, the Far East, Latin America and that we should lower standards over here. But this argument has been used many times in the past - only with different countries being cited (in the past it was Spain, Portugal, Greece etc). There will always be somewhere where standards and wages are lower. The standards adopted in the developed countries are helping to protect workers' health - and uncontrolled use of hazardous substances, such as the example in the slides, needs to be addressed in the developing world, and will be in due course as workers there become more organised.

In order to improve standards, professional expertise will be needed, including occupational hygiene. Although these skills could be provided by hygienists based in Europe, the USA and Australia, this is not a solution in the long term. The best approach is to develop the profession in the countries where occupational hygiene skills are required. The International Modules being developed in partnership by a number of occupational hygiene organisations, including BOHS and the Australian Institute of Occupational Hygienists should, hopefully provide a foundation for this.

IARC review of Category 1 carcinogens

In March, 2009, the International Agency for Research on Cancer (IARC) reassessed the carcinogenicity of metals, arsenic, dusts, and fibres previously classified as “carcinogenic to humans” (Group 1) and to identify additional tumour sites and mechanisms of carcinogenesis. Their findings are published in:

A review of human carcinogens—Part C: metals, arsenic, dusts, and fibres : The Lancet Oncology

Key points from this article include:

Metals

• The classification of beryllium and its compounds, cadmium and its compounds, chromium (VI) compounds, and nickel compounds as “carcinogenic to humans” (Group 1) was reaffirmed .
• Arsenic and inorganic arsenic compounds was classified as “carcinogenic to humans” (Group 1).

Asbestos

• Epidemiological evidence has increasingly shown an association of all forms of asbestos (chrysotile, crocidolite, amosite, tremolite, actinolite, and anthophyllite) with an increased risk of lung cancer and mesothelioma.
• Sufficient evidence is now available to show that asbestos also causes cancer of the larynx and of the ovary.
• The Working Group classified the evidence for an association between asbestos and colorectal cancer as “limited”.

Silica

• The Working Group reaffirmed the carcinogenicity of crystalline silica dust as Group 1. An increased risk of lung cancer was observed across various industries and processes.

Wood dust

• Wood dust was reaffirmed as “carcinogenic to humans”.
• Epidemiological studies report a strong association between exposure to wood dust and development of sinonasal cancer.
• There is strong evidence of carcinogenicity for hardwood dusts.
• For softwood dust there is a smaller riskthan for hardwood dust

Leather dust

• A particularly high risk of sinonasal adenocarcinoma was noted among workers with the highest exposure to leather dust.
• Leather dust was classified as “carcinogenic to humans” (Group 1).

Music lessons for conference organisers

I came across this on aWordPress blog http://returnon.wordpress.com/

I think the speaker makes some good points in his short presentation. Conference organisers everywhere take note!

Parrots or professionals?

The following article by the philosopher AC Grayling appeared in The Guardian on Saturday:

Knowledge and genius

I think it makes some very valid points which are relevant to education and particularly so with respect to the training of professionals.

In the article, Grayling states:

“there is no automatic connection between knowledge and intelligence“.

I agree wholeheartedly with this. Simply being able to reel off facts isn’t proof of ability to perform a task. Even a parrot can be trained to reel off lists of facts. Yet there is too much reliance on rote learning in the occupational hygiene profession where trainees are required to learn masses of facts for the BOHS modules, while there is relatively little testing of their ability to apply the knowledge to solving problems.

An enormous amount of information is available to us in the modern world - and it continues to expand exponentially. It is not only unrealistic to expect a professional to absorb and remember a mass of facts, it is, in my opinion, poor practice. It is more important to know how and where to locate information than to memorise it - and then to be able to use it to analyse and solve problems.

Tunnel vision

I went to look at a specialist manufacturing facility this week where they produce and handle small amounts if a highly potent compound. I've been asked to carry out a COSHH assessment for the process. As they weren't manufacturing I was given a "guided tour" of the process and was able to take a good look around at the facility itself and the control measures in place. My discussions with the production personnel concentrated on the control of the potent substance itself. Other substances used during manufacture were mentioned, but only in passing. Some of these presented health hazards (although they were clearly not as harmful as the potent substances), but the personnel were so focused on the potent that they didn't really make any comments on the hazards and risks from these other substances and the measures used to control them.

It's very easy to get "tunnel vision" with processes like this where a potent substance is being handled. What I mean by this is that so much attention is devoted to the main hazard that possible risks from other substances or agents can be forgotten. This can lead to problems if some of those risks are significant and aren't controlled. Although its clearly very important to ensure that everyone is aware of the risks from the main potent material, and that a very high standard of control is applied, attention also needs to be paid to other hazards to make sure that any risks they present are properly controlled as well.

Sir Humphry and the Age of Wonder

I think its important that people working in a particular field of expertise should be more than one dimensional and cultivate interests in other areas. I've always had a passion for history, literature and reading in general. A long time favourite book is Richard Holmes' "Footsteps", a book which combines biography, travel and autobiography. His biography of Shelley is also a favourite. So when I heard that a new book of his was due out that focused on the development of science in the "romantic age" I bought a copy hot off the press - even though it was in hardback, as I didn't want to wait the extra months it would take for a paperback edition to be published (mind you a half price offer made it even more tempting!).

As in Footsteps, Holmes covers the life of more than one subject and also wanders off down sidetracks related to the main theme. One of the main topics is the life of Sir Humphrey Davy. I've always had an interest in this pioneering chemist so was keen to read this section of the book. He is best known for his invention of the safety lamp and he is also credited with the discovery (or isolation) of sodium, potassium and barium. But there is a lot more to his life.



Humphrey Davy came from humble beginnings in Cornwall, being born in Penzance in 1778. In 1794 he was apprenticed to John Bingham Borlase, a Penzance surgeon, but in 1798 was taken on to Thomas Bedooes to work as a laboratory assistant in the latter's newly established Pneumatic Institution in Bristol. It was here that Davy was able to develop his talents as an experimental scientist, before finally moving to London in 1801 to work at the Royal Institution.

There's a tendency these days to separate arts and science - but Davy moved in both worlds, as did many other prominent artists and scientists at the time. He was a friend of Wordsworth and Coleridge who took an interest in his work, as did others, including Shelley and Keats - Davy even wrote poetry himself. Men of ideas were interested in more than one sphere of knowledge and culture.

As an occupational hygienist it was particularly interesting to read about Davy's experiments with gases in Bristol. He explored the effects of nitrous oxide and carbon monoxide by conducting inhalation studies on himself. On more than one occasion he came close to death by exposing himself to high concentrations of carbon monoxide.

One of the things I admire about Davy was his invention of the miner's safety lamp. Although this is surrounded by controversy (not least disputes about who first developed the lamp with George Stevenson) Davy was largely motivated by a desire to save lives (although the search for glory was a factor too, it has to be said) and he refused to take out a patent, even though strongly encouraged to do so. He wanted his lamp to be freely available. Sadly, although the lamp was intended to save lives it has been said that it actually caused the death of more men because the mine owners used the lamp as an excuse to send their workers into more dangerous workings. However, the ones really responsible for this were the greedy mine owners. Davy cannot be blamed for the misuse of his invention by others.



Although he had radical tendencies in his youth, he moved to the right in older age as he became part of the establishment (sadly this is too often the case). He also had a tendency to seek glory and credit for inventions and could be jealous of others who worked with him - notably Michael Faraday who started out as Davy's assistant. Nevertheless there is much about him to admire and Holmes, who is clearly sympathetic towards his subject, has written an educative and entertaining account of his life. And although the book as a whole is excellent, it was worth shelling out for a hardback book for this alone.

Shipping can be bad for health

I guess we usually think of shipping as more "environmentally friendly" form of transport compared to aircraft and motor vehicles. However, there was an interesting article in the Guardian today about the health risks of emissions from shipping.

Ships burn fuel oil - one of the "dirtier" fuels, containing high levels of sulphur. So emissions of sulphur dioxide are significant. The heat of the combustion process also generates another toxic gas - nitrogen dioxide. Both of these acid gases have harmful effects on human health and can also damage other living organisms. Particulate pollutants are also emitted.

Key points in the article include

• "just 15 of the world's biggest ships may now emit as much pollution as all the world's 760m cars"
• "pollution from the world's 90,000 cargo ships leads to 60,000 deaths a year in the US alone and costs up to $330bn per year in health costs from lung and heart diseases."
• 1,000 Danish people die prematurely each year because of shipping pollution and shipping emissions cost the Danish health service almost £5bn a year, mainly treating cancers and heart problems.

Dealing with these health related problems will not be easy. Control over shipping is notoriously difficult as a ship isn't based in one country. Concerted international action will be needed which can be easily circumvented by countries which allow ships to register under a "flag of convenience"

The economics of childhood lead poisoning

Following on from my post on lead yesterday, I stumbled on the following article

Childhood Lead Poisoning: Conservative Estimates of the Social and Economic Benefits of Lead Hazard Control

Published on the Environmental Health Perspectives website.

The study involved undertaking a cost-benefit analysis which quantified the social and economic
benefits to households of lead paint hazard control balanced against the investments needed to minimize exposure to these hazards. The conclusions of the study are

"there are substantial returns to investing in lead hazard control, particularly targeted at early intervention in communities most likely at risk. Given the high societal costs of inaction, lead hazard control appears to be well worth the price."

The analysis is really only relevant to the USA as the economic factors, which include the costs of health care, costs of education, earnings, and taxes are only applicable there. Nevertheless I'm sure that a similar analysis undertaken in other developed countries would reach similar conclusions. Hopefully the findings are convincing enough to influence regulators. However, in the developing world different conclusions would probably be reached if the need to control lead was considered only from an economic perspective. Is the health of children there any less important even if the balance in the cost-benefit equation is different?

Health is not just an economic issue. Although economic arguments can help to persuade governments of a need to take action, the right to good health goes beyond that. Ethical considerations must surely carry more weight.

Hypothermia

Working outdoors in Alaska

A recent posting on the Catlin Arctic survey blog discusses the effects of working in temperatures of below -40 degrees centigrade.

Hypothermia is the result of general cooling of the body below 35 degrees C. Early symptoms include tiredness, muscular weakness and confusion. Below 30 to 32 degrees shivering stops and unconsciousness can occur. When shivering stops there is a rapid decrease of body temperature. Death may occur at where the core temperature is around or below 28 degrees C.

The body produces heat and the harder you are working the more heat is generated. At low temperatures we are likely to lose heat to the environment, the extent of this heat loss, however, will be influenced by the amount and type of clothing being worn. Chemical protective clothing can present a particular problem. Even in cold environments it is possible to suffer heat stress and strain where heavy work is being undertaken and impervious clothing is worn which does not allow enough of the heat produced to escape. This is particularly relevant to chemical workers and emergency response personnel.

The Catlin team are pulling heavy sledges of 110 kilos each an average of 6 nautical miles a day. Their clothing is of a high standard in terms of the insulation it provides, but insulation alone is not enough to prevent hypothermia in such extreme conditions as they are experiencing. as the team Doctor notes

“All clothing can do is slow down the process of losing heat. “The only way they can keep the hypothermia at bay is to keep moving and to keep eating”.

Handel exhibition suggests his poison was the lead in his wine

I spotted an interesting article in the Guardian last week, reporting on a theory that the composer Handel suffered from lead poisoning


Lead acetate used to be used to sweeten wine and this is suggested as the source of lead exposure for the composer. I've even heard it suggested that the fall of the Roman empire could be attributed to the same reason as they, apparently, were very fond of sweet wine and used to add lead acetate to it. There is a useful summary of the history of lead exposure here on the USEPA website

Lead and its compounds are highly toxic. The main concerns are its chronic effects (due to long term exposure) particularly as it is accumulates in the body, remaining there for a long time after exposure.

Its principle effects include

• anaemia,
  
• irritability, tiredness,
  
• effects on the nervous system leading to muscle weakness and, in extreme case, paralysis,
• kidney and liver damage
• gastrointestinal disturbances
• effects on IQ, particularly in children
• It is a teratogen, that is it can affect the unborn child when the mother is exposed, leading to spontaneous abortion, still birth or decreased birth weight,
  
• fertility problems in males
  

Inorganic lead compounds are are also classified as "probably carcinogenic to humans" by
the International Agency for Research on Cancer (IARC)

For a thorough summary of its effects see the document Information on lead from the UK Health Protection Agency

Exposure to lead in the developed world has fallen dramatically due to increased awareness, stringent legislation in the workplace (such as the Control of Lead at Work Regulations in the UK), environmental regulation and the reduction of lead in products to which the general public could be exposed. The banning of lead in petrol being a particularly important measure. Consequently cases of lead poisoning are relatively rare.

However, it is likely that lead exposure is increasing in the developing world as lead and its compounds are still widely used in manufacturing and with the rapid growth of industry in India, China and other countries it is likely that the exposure of workers and the general public will increase. Control measures to reduce the exposure of workers and minimise emissions to the environmental are likely to be considerably less stringent in newly developing countries than in the developed world. A report by the World Health Organisation discusses these issues and concludes that:

"Public health measures should continue to be directed to the reduction and prevention of exposure to lead by reducing the use of the metal and its compounds and by minimizing lead-containing emissions that result in human exposures."

Consultancy fined after inaccurate asbestos survey

From a recent HSE Press Release

"Bestoff Services Ltd of Chorleywood, Hertfordshire pleaded guilty to breaching section 3(1) of the Health and Safety at Work etc Act 1974. They were fined £3,000, ordered to pay costs of £2091.70 and a victim surcharge of £15.

The company carried out an asbestos survey on a site at Unit 27, Nuffield Way, Abingdon in February 2008 and reported that the site contained no asbestos. Two members of staff began work on the site the following month and part of their job involved removing panels of fibrous board."

Full details are available at:

Company fined after inaccurate asbestos survey leads to exposure

A lot of money has been made by companies carrying out asbestos surveys in recent years - not all of these surveys have been done competently. Occasionally someone gets caught out - but I'm sure a lot don't.

The HSE has tried to regulate asbestos consultancy companies by insisting on accreditation. I have never been convinced that this was the right way to address the problem. Some companies who are competent to carry out surveys and have the professional integrity to ensure that they are done properly, but who don't carry out asbestos work exclusively, find the cost of accreditation prohibitive and so pull out of the market. On the other hand, there is no guarantee that that companies who can jump all the hurdles created by UKAS and are prepared to carry the costs involved, will carry out the surveys competently in practice or that they adopt professional standards with respect to reporting their findings.

Fortunately, in the case concerned, the client company were interested in their employees' health and took the appropriate action once they became suspicious.

Frostbite

There's a good summary of the effects of frostbite, complete with some gruesome photographs, on the Catlin Arctic expedition website. Worth a look.

Green buildings?

Kamal Meattle's talk from the recent TED conference has recently been posted on the TED website.



I've already embedded the slides from the talk on a previous post.

The idea of using plants to clean up indoor air has been around for quite a while now. This talk is about a project which utilised three different plants in a building in New Dehli. The results sound interesting but both the talk and slidedeck give relatively few details. I'd like to find out more but there isn't any further detail on the websites referenced by TED and in the slides. A quick "Google" hasn't turned up anything and I've not been able to locate any relevant papers in the public domain. So I'll have to reserve judgment on how effective these plants have been until I've had chance to look into this in more detail.

"To sleep, perchance to dream"

I've been following the Catlin Arctic survey blog for updates on the expedition to the Arctic to measure the thickness of the sea ice. As well as the environmental perspective there are a number of aspects of the expedition which are of interest to occupational hygienists. Their blog and website includes information on dealing with exposure to cold including the clothing they are using and their experience of living in a cold environment.

There was an interesting post on their blog today written by the expedition's sleep analyst, Mary Morrell. This might seem like a rather strange job, but lack of sleep and disturbed sleep patterns can lead to ill health. To quote from the blog post

"Insufficient sleep (usually thought of as less than 7 hours per night) causes tiredness and fatigue. Alertness is reduced and thought processes slow down. In particular, sleep deprivation leads to slower reaction times."

In the workplace this is relevant for shift workers and personnel working unusual shift patterns and the impact on their health isn't usually considered during workplace risk assessments. So the experience gained during the expedition could have some lessons for us and it will be worth keeping an eye on the blog for any further posts on this topic.

Whats wrong with what we eat?

This video, which I found on the TED site, might be useful for my students on the Open University course T210 (Environmental control and public health) who are going to be starting the block on Food Processing and Distribution in a couple of weeks time.



It raises a few of the points covered in the block and would be a nice gentle introduction to supplement the course written materials, particularly as we don't have a tutorial scheduled during the study time for this block

Nanoparticles

I came across the following video slideshow by Andrew Maynard (2020science.org), a researcher in nanotechnology. It's a nice, gentle introduction to nanoparticles and their properties.


Nanotechnology - Managing the Small Stuff, Explained from Andrew Maynard on Vimeo.


The key points he makes about these new materials are

• the particles are small
• they are "strange" - they don't behave how you might expect and the properties of a substance manufactured or created as a nanoparticle can be different than the same substance in the form of larger particles
  
• they are "sophisticated" - in that they can be used to manufacture complex products with advanced uses
  

There are inevitable concerns about the toxicity of nanoparticles and the risks from exposure, both from an occupational and environmental context.

• the small size of the particles means that they can, potentially, be absorbed easily into the body by inhalation AND skin contact (there is evidence that some particles can be absorbed through intact skin)
• nanoparticles are much more likely to be absorbed into the blood via the lungs than their larger cousins. Once absorbed they can make their to other organs where they may be able to exert toxic effects.
  
• their small size also means that they can be potentially absorbed into cells where larger particles of the same substance would not
• the "strangeness" of nanoparticles means that it can be difficult to predict what their toxicological properties will be, even where there is a good understanding of the toxicity of larger particles of the same substance
• In some cases, effects such as cancer are due to the physical form of particles and their Small size (aka asbestos fibres) rather than their chemical nature

It is too early to now whether any of these concerns are likely to be borne out in practice. However, its an area where a lot of research is taking place.

Another week another course finished. This time it was M101, "health effects of hazardous substances".

As usual, the exam was disappointing, in that the questions were not all of a high standard. One of the part B questions in particular, was of concern. Although the overall question was OK - it asked about the hazardous effects of four relatively important substances, it also asked about how the substances could be "detected" required the candidates to list the relevant occupational exposure limits.

First of all what was meant by "detected"? Do they mean how do the senses detect the substances, how they can be detected by biological monitoring or how they can be detected by air sampling? It is not clear at all. And if they mean any of these aspects, they are outside the scope of the syllabus. An example of poor question writing.

I also think that expecting candidates to list exposure limits is unreasonable. For a start, there is nothing in the syllabus that requires it (limits aren't even mentioned). If the examiners do think it is fair (I assume they do given that they set the question), then it would imply that the candidates must know all the limits in EH40 as there is nothing to indicate that only a small selection need to be memorised. This is not just unreasonable but I would contend that it is bad practice to attempt to remember the contents of EH40. First of all there are more important things that need to be held inside our limited memory banks. Secondly limits change and I think that it is much better to encourage hygienists to look them up and ensure that the most current one is applied. Its easy enough to do this - especially as the main reference source is the pdf file posted on the HSE website (now that they don't publish a hard copy every year).

We should be training candidates about what limits are, where to find them and how to locate them - but not expecting them to memorise them.

Featured on Slideshare

I just received an e-mail telling me that my presentation Pollution And Human Health is currently being showcased on the Slideshare 'Health & Medicine' page.

Pollution And Human Health

This is a slideshow of my lecture to MSc students at Manchester Unversity

Pollution And Human Health

View more presentations from mikeslater. (tags: pollution environment)

Intro To Occupational Hygiene

This presentation was originally intended as an introduction to occupational hygiene for oil industry personnel. I've modified it slightly so its more generally applicable (although it still has an oil industry "slant").

Intro To Occupational Hygiene

View more presentations from mikeslater.

Introduction To Toxicology

This is an introductory presentation on toxicology.

I'll be using a slightly expanded version on day 1 of the M101 course that we are running in Chester next week.

Introduction To Toxicology

View more presentations from mikeslater.

Cupola furnace

I took this picture recently of a cupola furnace at a small foundry. Scrap metal and coal are loaded into the top of the furnace and the coal set alight to melt the scrap and produce molten metal which is used to manufacture castings.

As there is insufficient oxygen for complete combustion, carbon monoxide is generated. Hydrogen sulphide can also be produced due to the presence of sulphur in the coal. Both of these gases are highly toxic and have to be extracted to minimise the risk to the operators. Some of the gases dissolve in the molten metal and can gas off as it cools, so there can be some risk during the casting operation itself.

This is a good example of how hazardous substances can be generated during a process and which are often forgotten by inexperienced or untrained people carrying out health risk assessments.

A number of years ago I got involved with a company (NOT the one shown in the picture, I should point out) where a worker had been exposed to high concentrations of carbon monoxide when inspecting the furnace when a leak occurred. The company concerned had employed a safety consultant to carry out COSHH assessments for them. Unfortunately he based his assessments on the material data sheets for the substances bought by the company. There were no data sheets for carbon monoxide or hydrogen sulphide as they aren't bought in so there was no mention of two of the most serious risks in he foundry - i.e. potential exposure to the gases. There were other hazards he didn't consider too - metal fume created during melting and casting and exposure to respirable crystalline silica during "fettling" (the grinding of the finished castings to remove rough edges) - because again, these substances are created by the process and are not bought in.

Although most people seem to think that COSHH requires an assessment to be carried out for substances, this isn't actually the case - the assessment should actually cover the "risks created by work" where workers can be exposed to hazardous substances. Its best to start by considering the process and what workers and others can be exposed to - both bought in substances and any that can be generated by the process itself. Quite often it is the latter that present the most significant risks, as is the case with the cupola furnace and other foundry operatons. Listing the substances bought in and using the supplier's data sheets as the basis of the assessment is likely to lead to significant risks being missed.

Note: COSHH is an acronym for the British Control of Substances Hazardous to Health Regulations 2002

Evaluation

There's a management cliche that used to be quite popular a few years ago - "you can't manage what you can't measure". I'm afraid I couldn't agree less!

This may seem strange coming from an occupational hygienist, particularly as where anyone knows anything about what we do they assume we spend our time making measurements of dust, fumes, vapours noise and other hazardous agents. In fact evaluation is only part of what an occupational hygienist does and even then measurement is only one technique that we use to evaluate risk. Our prime objective is not to carry out measurements, but to control risk. In order to do that we need to know which hazardous agents present in the workplace are likely to present a significant risk - so risk evaluation is an essential prerequisite to control - but it is a means to an end, not an end in itself.

As many workplace hazards are not visible to the naked eye it s not always easy to recognise where a significant risk is present. In these situations, measuring worker exposure to the contaminants can help us to decisions on risk. However, sometimes it is obvious that a problem exists. Just take a look at the picture above. Its pretty obvious that the worker is exposed to a high concentration of fume and that improved controls are needed o protect his health (and possibly the health of others n the workplace). In such cases its better putting our time and effort into solving the problem rather than quantifying it.

Life at the Extremes

I was running the BOHS module on Thermal environment, non-ionising radiation and lighting last week. That's one hell of a course to teach. So many topics to cover and most of the attendees hadn't much experience of them.

For anyone wanting to know more about heat and cold stress, this book by Frances Ashcroft is a nice gentle introduction. It is very well written, easy to read and explains the basic principles very well with some good real life examples.

As well as heat and cold, it covers other challenging environments that might be of interest to occupational hygienists and physicians - high altitude and hyperbaric (high pressure).

Training professionals

Its been a tough week. I've been running BOHS module M201 this week with 15 delegates, none of whom have had any experience of the topics covered. The problem with the course is that there is so much to cover, particularly when the concepts are new. And as I discussed in a previous post quite a bit of the material we have to cover is not really relevant to modern practice.

M201 isn't the only BOHS module where we have this problem. Most of them have too much content for a one week course where the exam is taken at the end of the week. This is compounded by the examinations which concentrates on testing the candidates' memory rather than understanding of principles and their ability to apply them.

The modules are intended to allow trainee occupational hygienists and other people carrying out some aspect of occupational hygiene as part of their job to develop knowledge and skills they need to carry out the job competently. This requires more than just knowledge of facts.

"Bloom's taxonomy" is a well known concept used by educationalists. It was developed in 1956, by a group of educational psychologists led by Benjamin Bloom. Its a way of looking at the different types of learning, setting them out in a hierarchy with six levels, often set out in the form of a pyramid. The lowest level is "knowledge", involving learning facts which are then recalled or recognised and the highest level, is "evaluation", where judgements are made about the validity and quality of information.

The way the BOHS modules are currently set up we are mainly developing and testing knowledge with much less emphasis on the higher level skills. I would contend that in the modern world of work professionals need to absorb fewer facts and develop the ability to find the information they need, understand it (i.e. comprehensive) and then be able to apply it and use it effectively (i.e. application, analysis, synthesis and evaluation).

There are two dimensions to knowledge - breadth and depth. During a short duration course there is only so much we can expect learners to absorb. In simple terms, if we are aiming from breadth we can't expect knowledge to be too deep. Its only reasonable to expect depth of knowledge in a narrow range of topics. The BOHS syllabii require coverage of a lot of topics - i.e. breadth, but the exam questions are such that deep knowledge of each topic is required. This is a problems that needs to be addressed.

As I see it, there are a number of specific problems that need to be addressed. Currently, the module structure means that trainee operational hygienists are expected to have deep knowledge of:

• health effects of substances that are rarely, if ever, encountered in practice. How many hygienists in modern industry need to know that a symptom of excessive exposure to vanadium pentoxide is a green tongue? How many of us have actually seen one? Do we really need to know that arsene exposure can lead to “port wine urine”? How many of us have ever seen “wrist drop” caused by excessive exposure to lead? Just think of how much exposure to lead would be required for that to happen. These are things that candidates taking BOHS exams are expected to know. They are easy questions to write, but are they really relevant?

• sampling methods for a wide range of specific substances - even though this information can easily be looked up in the standard methods which have now been made freely available on the Internet by HSE and NIOSH. I think it is reasonable to expect operational hygienists to be familiar with the basic methods, but they should be encouraged to check specific details in the written method rather than rely on their memory with the consequent risk of making a mistake,
  details of analytical procedures. A long time ago the person taking a sample may have performed the analysis. With the exception of asbestos, that is rarely the case, yet our examination system persists in requiring trainee operational hygienists to learn details on analytical techniques. I can see the value in knowing what methods are appropriate for the main classes of substances we have to sample, but not for knowing the specific procedures adopted by the analyst,

• a large number of equations – is this really necessary in the real world of work? If an equation is needed for a calculation it is easy enough to look it up (if necessary BOHS provide handbook of common equations that can fit in a pocket or electronic version that could be downloaded onto a laptop, PDA or mobile phone.) They need to be able to select the appropriate equation (not as easy as it seems) and be able to use it. Wouldn't it be better to test that than the ability to memorise it. Most colleges and other bodies (including the Institute of Acoustics) provide equation sheets for exams these days.

• For some exams candidates are expected to be able to remember specific exposure limits for chemicals, and details from other standards (including remembering exposure limit values for non-ionising radiation and the TLVs for heat stress) and other similar information such as the wording of R phrases. All of these things can be easily located and looked up. Knowing where to find this information and being able to understand it is important but why does a trainee hygienist need to memorise it? In reality it will be forgotten a few days after the exam unless the information is used regularly. Again, surely it is more appropriate to expect the trainee to learn how to find information, understand it and use it.

In my working life I've seen major changes in the ability to access technical information. 30 years ago everything was printed and to obtain information you had to have access to books, journals, other documents. This meant you couldn't carry around information easily and important information which needed to be accessed quickly had to be memorised. Today things are different. Its much easier to access to information via the Internet or electronic documents that can be kept on mobile devices such as laptops, PDAs and even mobile phones. In addition, the amount of information we need to refer to continues to grow. Human memory has limited capacity, and our knowledge will rarely be completely up to date.

Currently we expect trainee hygienists to memorise large amounts of information and be able to reproduce it. There is little emphasis on interpretation, application and the higher level cognitive skills. In my view it would be much better if we changed our emphasis to a new approach where we required trainees to be able to :

• understand basic principles


• have knowledge of a smaller number of key facts


• know what information sources are available and which are relevant


• know how to search for information


• be able to interpret the information.

To support this the BOHS and Faculty could look at

• providing guidance on information sources


• making available reference material such as key equations and principles in a handbook/manual, probably in an electronic format that could be downloaded and which would be relatively easy to keep up to date.
  
  
  
  
  

Plants and indoor air quality

The TED conference has just started in California. It would be nice to be there enjoying some warm sunshine rather than shivering in the cold. At least Wigan hasn't been affected by the snow which has caused London and other parts of the country to grind to a halt!

I noticed the following posted on the TED blog - the slide show from a talk that took place today.

How to Grow Your Own Fresh Air - TED 2009 Talk

View more presentations from jaymeattle. (tags: plants greenhouse)

Plants are often proposed as a way of improving the indoor environment and there have been claims before about how they can remove air pollutants in "sick buildings". They can also, possibly, have other benefits by raising humidity in dry buildings, particularly in the winter in Britain when damp cold air is brought into the building and warmed up causing the relative humidity to plummet with consequent problems due to dry eyes, sore throats etc. The claims made in this presentation are pretty dramatic. I'll be interested to watch the video when its eventually posted on the TED site and would like to see more detail of their results to see whether the claims are justified.

(TED is an annual conference that defines its mission as "ideas worth spreading". The lectures, called TED Talks, cover a wide range of topics. The talks from past events are gradually being published via their website from where they can be viewed directly or downloaded)

Thermal stress

I'm absolutely shattered this evening. I've just got home after finishing day 2 of a BOHS module course - M201 covering thermal environment, lighting and non-ionising radiation. Its a lot of content to cover. I've had to try to compress thermal environment into two days for an audience who have had little previous involvement with the subject.

As usual with BOHS modules there is far too much content. It is particularly frustrating in that the thermal environment section of the syllabus includes a lot of material which is well out of date, does not have much relevance to current practice and is of historical interest only.

Covering some of the older, outdated material can reinforce understanding by showing how modern approaches evolved, but that is a luxury when time is limited. It means that I can't really devote enough time to teaching and reinforcing the material that is really relevant to today's practice. It also means that I haven't much time available for practical exercises that would really reinforce learning. The outdated material needs to be weeded out so that proper emphasis can be given to the information and skills that hygienists need to carry out their jobs.

I'm afraid this is par for the course with BOHS modules.

Making training stick

I've just finished reading "Made to stick" by Chip and Dan Heath - a book widely recommended on various blogs on presentation and management. Its about how to get ideas to "stick", and the principles outlined can be applied in various contexts, but the one I'm interested in is teaching and training.The core idea in the book is that to make ideas stick the message need to have a number of attributes, summed up by the acronym SUCCES. They should be

• Simple


• Unexpected


• Concrete


• Credible


• Emotional


• use Stories

The last of these is particularly important as stories usually involve concrete examples, can get to the core of the idea and can be framed to include unexpected and emotional aspects. The Heath's practice what they preach with stories (lots of examples) forming the basis for the book.The occupational hygiene profession is not very good at making things "sticky" - the very name we use for our discipline is perhaps a good example of this!

Although we often can work out what our core ideas and principles are, we are not always very good at using the other aspects discussed by the Heath's to put them across to an uninterested audience we are trying to influence, whether management, workers or regulators. For example, I was discussing the COSHH principles of good control practice with Adrian Hirst a few days ago, and we both agreed that while the principles are good and sensible, they are anything but "sticky" and its perhaps not surprising that very few people, including many general safety practitioners, have not really heard of them. From a training and teaching perspective, making ideas "sticky" is important if the learners are to remember what you've tried to get across, and the SUCCES principles can be applied to make the instruction more memorable.

Making things "simple" doesn't mean "dumbing down" but making sure ideas, however complex, are put across in a way that can be understood by learners new to the principle. Things that seem obvious to an expert need to be carefully explained. This can be made easier if the ideas are illustrated by concrete examples. Every good trainer will have "war stories" that can be used to illustrate application and implementation of the principles. Case studies too are types of stories and can be based on concrete examples and are a good way of getting the learners to think through the principles. The stories and case studies clearly need to be credible if they are to be seen as relevant by the learners.

The idea of using emotion might seem a bit airy fairy but is really about making the ideas relevant to the learners by showing them that what they are learning is relevant to them, either as individuals or as part of a group. Unexpectedness is probably the most difficult principle to apply - I think that it can only be used sparingly - you can't make everything unexpected. However its a good way of waking up the audience and grabbing attention and can be particularly useful during awareness type training, particularly where the audience might be uninterested, and can help to get the emotional "buy in" you are trying to achieve.

One thing isn't covered in the book, which is particularly important in making training and teaching "sticky". The book focuses on getting a message across and making it stick by presenting people with information i.e. by presenting the information verbally or in writing. Learning isn't just about listening and reading- quite the contrary. People learn best by doing - sometimes finding things out for themselves or reinforcing the points put across in presentations and written material. Perhaps some of the ideas in the book could be applied to practical exercises. As I've already mentioned above, they can be applied to designing effective case studies.

So all in all, a useful book. The ideas it contains have certainly stuck with me!

When the "right" glove is the wrong glove

There are many situations where people at work can have direct skin contact with chemicals, particularly hand contact. It is often taken for granted that tasks such as cleaning will involve wiping down with cloths, or something similar, soaked with a solvent or other chemical which are held in the hand. Many of these chemicals can cause skin problems or can be absorbed through the skin contributing to the overall body burden. The panacea in such cases is to provide chemical protective gloves. The trouble is, this can create more problems than it solves.

With any personal protective equipment it is important to understand the limitations and know how and when the protection is likely to fail, because when it does it "fails to danger" - there is no back up. In the case of gloves, and other chemical protective clothing, failure can occur in three main ways

• penetration -where there is physical damage to the material resulting in a physical breach in the protection
• degradation - where the glove material is attacked by the chemical or is affected by other factors such as sunlight
• permeation - where the molecules of the chemical work their way through the molecules that make up the glove material

The time taken for the chemical to permeate through a particular glove or garment is known as the breakthrough time. This is dependent on both the permeation rate (the rate at which the particular chemical permeates through the material, which depends on the type of polymer used) and the thickness of the garment. The thicker the glove material the greater the chemical resistance. But thick gloves can impair grip, dexterity, and safety.

Many chemicals, particularly common solvents such as trichloroethylene, toluene and xylene pass through most common polymer materials very rapidly. Depnding on the glove material and design, the breakthrough time is can be as low as 10 minutes and rarely greater than two hours. If gloves have to be used, it's important to make sure that the "right" one has been selected - one that will offer appropriate protection against the chemical of concern. The breakthrough time gives the effective usage time for the glove which should be changed on ths basis.

Too often, even where appropriate gloves have been selected the maximum usage time is not specified. Workers continue to wear the gloves until they spot obvious faults. However, this presents a problem as that the user will not know that breakthrough has occured. Its easier to spot degradation (although this often ill only happen after breakthrough has occured). Large tears and holes can e spotted fairly easily, but small "pinpricks" may not be noticeable.

Often workers continue to use gloves long after breakthrough has occured. In many cases I have encountered they use them for several weeks or months before replacing them - even though they are unlikely to offer proper protection after more than a few hours at best. The trouble is, people wearing gloves think they are protected and have a false sense of security - adopting practices they wouldn't think of using if they knew that they weren't protected. And once the chemical has permeated through the material it is in direct contact with the skin and the risk of harm can actually be increased. So in these cases, the "right" glove can be the "wrong" glove

Personal protection has to be a last resort, and this is just as relevant to gloves as other types of personal protection. Where thre is a risk of skin contact with cjemicals the best approach is to look to change the working method tso that skin contact doesn't occur, or is a least minimised to the lowest level practicable. For example, rather than using a solvent soaked cloth held directly in the hand, simple applicators could be used (something like a roller or "paint pad"might be options). A litle imagination is all that is needed.