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#1 Posted : 27 July 2009 12:06:00(UTC)
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Posted By Barrie (Badger) Etter As Swine Flu seems to be the topic of the day, a random thought crossed my mind (dangerous I know for a Monday). The government advises us to bin tissues once used. Presumably those tissues go to landfill? My question is what chance is there of the flu virus reaching the water table in an unlined landfill site and what chance of it reaching the human populace if that water is abstracted? Also what benefit of incinerating same? Debate is now open. Badger
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#2 Posted : 27 July 2009 12:10:00(UTC)
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Posted By Swis The chances are nil as the virus can not stay live for long wihtout a host cell.
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#3 Posted : 27 July 2009 12:38:00(UTC)
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Posted By Dave Merchant Barrie - effectively zero given the dilution factor and natural deterioration of the H1N1 viral envelope when exposed to air, UV light, the chemical soup of landfill sites, etc.; eventually destroying it. Swis - will you please stop talking about viruses as if they're alive. THEY ARE NOT. You can't kill a virus. It doesn't respire, grow, eat, generate internal energy, self-reproduce or have a metabolism, nor do they have any structural activity when they're outside a cell. It's a blueprint in a bag, period. You're also only correct by chance of phrase - many viruses can remain viable for years, decades, even centuries depending on their environment.. Something has to damage them, or the default is continued viability. They can float through space and still infect someone, but the conditions viruses are exposed to outside the body (UV light, chemicals, etc.) are usually sufficient to destroy them anywhere from a few minutes to a few decades later.
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#4 Posted : 27 July 2009 13:10:00(UTC)
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Posted By Swis A few things to clear here : 1) we are talking about a public health and safety forum therefore there’s no harm in using the terms ‘live’ for the viruses. If we can use the word ‘live’ for electricity , surely we can use it for viruses. If you want to discuss the technicality then we’ll have to find another forum. 2) Definition of ‘live’ as described having to respire, grow, eat, generate internal energy, self-reproduce or have a metabolism is completely flawed. 3) There’s no need to teach me of different ‘life’ spans of the viruses. I’ve used the word ‘virus’ in my previous post which corresponds to Flu Virus described by Badger (thread). I only addressed the question asked in this thread. 4) I believe in constructive debate and would like other to do the same. No personal comments please. By the way, what is “the chemical soup of landfill sites”? Never heard of that ‘soup’…:-)
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#5 Posted : 27 July 2009 13:19:00(UTC)
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Posted By martinw Dave see the following - how to kill a virus http://health.howstuffworks.com/light-virus.htm Fascinating.
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#6 Posted : 27 July 2009 13:24:00(UTC)
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Posted By safetyamateur Barrie, why did they start calling you 'Badger' when the logical choice would have been 'Henry' or 'Goag?
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#7 Posted : 27 July 2009 13:25:00(UTC)
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Posted By martinw Or Jets?
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#8 Posted : 27 July 2009 14:01:00(UTC)
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Posted By Barrie (Badger) Etter Badger came about from work colleagues when on shop floor many years ago. Something to do with the dark stripes of hair amongst the silver - started turning when in early thirties. Alternatively my inquisative nature like a Badger to ask questions when I don't know the answer, better than being called Oi! W several dots r =O} Badger
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#9 Posted : 27 July 2009 14:03:00(UTC)
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Posted By martinw My favourite butter.
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#10 Posted : 27 July 2009 14:10:00(UTC)
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Posted By Tabs From my layman's understanding of some rather official-looking guidance read a while back, the tissue (based on cellulose) will desiccate the virus, thus interrupting its ability to remain viable.
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#11 Posted : 27 July 2009 14:17:00(UTC)
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Posted By Phil Rose Dave - I am no virus expert by any means, and I don't always agree with some of his posts but surely Swis's use of the term 'live' is one that we all understand as being accepted terminology to the majority?
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#12 Posted : 27 July 2009 14:23:00(UTC)
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Posted By Nicholas Sutcliffe This is just to clear up the understanding, I’m off for the rest of the week so this is loke a Friday for me: Source: Dictionary.com Live–adjective 1.being alive; living; alive: live animals. 2.of, pertaining to, or during the life of a living being: the animal's live weight. 3.characterized by or indicating the presence of living creatures: the live sounds of the forest. 4.Informal. (of a person) energetic; alert; lively: The club members are a really live bunch. 5.full of life, energy or activity: His approach in any business dealing is live and fresh. 6.burning or glowing: live coals in the fireplace. 7.having resilience or bounce: a live tennis ball. 8.being in play, as a baseball or football. 9.loaded or unexploded, as a cartridge or shell: live ammunition. 10.made up of actual persons: to perform before a live audience. 11.(of a radio or television program) broadcast while happening or being performed; not prerecorded or taped: a live telecast. 12.being highly resonant or reverberant, as an auditorium or concert hall. 13.vivid or bright, as colour. 14.of current interest or importance, as a question or issue; controversial; unsettled. 15.moving or imparting motion; powered: the live head on a lathe. 16.still in use, or to be used, as type set up or copy for printing If we can have a live tennis ball and a live colour and a live TV show etc etc, I’m sure it’s ok to have a live virus. have a happy week all, and dont let the nitpickers get you down.
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#13 Posted : 27 July 2009 15:22:00(UTC)
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Posted By Dave Merchant A 'live' TV show is semantically different to a 'live' squirrel or a 'live' conductor. The fact they use the same spelling is irrelevant. Eats shoots and leaves. Some of you may not care what a virus is, and fine - but I'm attempting to ensure people are given accurate information as despite the forum disclaimer, they do take this stuff and run with it. Virologists' reason for not calling a virus a living thing is that it implies it has life-related properties, such as the ability to die of old age, the ability to reproduce, eat, grow, evolve, etc. - it's why we no longer use the term "killed virus" when talking about vaccines, rather "inactivated", and why antibiotics have no effect on them. To control viruses it's important to understand what they are and are not, so answers to questions like the one starting this thread make sense to people. Viruses spend the overwhelming majority of their time in the extracellular space, either inside your body or outside it, but NOT inside a cell. The cell is simply the production facility, and as soon as the cell has replicated a batch it is destroyed, thus allowing them to escape. The mere presence of a virus in your body is utterly harmless, but trillions of exploding cells are going to make you ill. To some it may seem I'm picking at phraseology, but to say "a virus cannot stay live for long without a host cell" (sic) is akin to saying "a car cannot stay alive for long without a car factory". Bacteria are entirely different - they are very much alive, and do the things required of that definition, such as reproduction. As a result, managing them in both patients and the environment is markedly different. In the context of the landfill site, water treatment, etc., bacteria can reproduce exponentially given a food source, and so present a major risk. Viruses don't, and so don't.
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#14 Posted : 27 July 2009 15:28:00(UTC)
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Posted By Ian Blenkharn Live - No But the question relates to survival of the infective particle in landfill. The practical answer is no. After a year of detailed study of virus survival on and in soil, and in landfill in particular, thanks to a commission from RoI, I have reviewed in great detail the survival of a wide variety of virus agents and other pathogens from waste. Dilution factors play a big part, and if virus contaminated items are exposed (should not happen in a sanitary landfill) then dessication and sunlight quickly reduce infectivity to zero. Within the landfill matrix, virus particles bind to clays and soils effectively reducing horizontal movement. Leachate is highly toxic primarily due to its pH. No doubt it happened in years gone by, but no active landfill site exists in the first world where leachate contamination of the water table is a reasonable possibility. There is a remarkably complex literature concerning virus survival in soil and in landfill. Despite the evidence for very rapid decline, it is necessary to discuss the practicalities - the opportunities for exposure are non-existent. For waste handlers, ie those handling fresh clinical wastes and/or domestic refuse, the risks of exposure are considerably greater and some basic hygiene measures would be particularly helpful though even in these circumstances the additional risks are probably small. DoH has rushed out some temporary guidance for waste handlers and with the Inst Wastes management we are working on something a little more specific. If anyone has particular concerns they can get in touch directly.
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#15 Posted : 27 July 2009 15:37:00(UTC)
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Posted By Swis You may not like the idea of me using the word ‘live’ for a virus but you must not deny the fact that virus is one of the species. Although the virus can not replicate without a host cell, you can not compare it like a stone, or anything ‘non-living’… And of-course antibiotic wouldn’t work against viruses because they are made for bacteria not viruses. Anti-virals on the other hand are potent drugs used to ‘kill’ virus and they do work perfectly fine… Swis
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#16 Posted : 27 July 2009 15:45:00(UTC)
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Posted By Barrie (Badger) Etter Ian / Dave Thanks for taking time out to satisfy an inquisitive Badger. One more question - From the time the virus leaves a host / carrier, how long before it is no longer a viable 'threat' if it does not find another host? At landfill I presume there are rats - What possibof them becoming carriers? Badger
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#17 Posted : 27 July 2009 15:49:00(UTC)
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Posted By Barrie (Badger) Etter I meant to say - What is the possibility of rats becoming carriers of the virus.
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#18 Posted : 27 July 2009 17:16:00(UTC)
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Posted By Ian Blenkharn I don't know the answer to this, and I am not aware of any evidence in the literature - quiet frankly I doubt anyone has bothered to research the issue! Intuitively, I would say its not a problem. Landfill sites are busy places where rodent control should keep on top of such problems, If rodents or birds or insects etc could access infective materials the amount they might carry is small and the likelihood of onward exposure is surely small - after all, a rat will run away and flies don't sneeze! I have no information as to the pathogenicity of influenza virus in rodents - they may be susceptible but if they are there is no certainty if would result in a respiratory infection as it does in humans. Given the huge number of potentially harmful micro-organisms deposited in landfill sites there are very few human infections even among staff working on site. As always, basic personal hygiene is adequate. Trouble is how often you see refuse collectors munching on a bacon butty in the vehicle cab, with their gloves on the dashboard and as much muck on their hands as on the gloves that the were wearing. And of course, no thought of hand hygiene!
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#19 Posted : 27 July 2009 17:43:00(UTC)
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Posted By John Richards There you go, another H&S failure> Put a sign in the cab: "no food to be consumed in here" But since they are still alive, their hygiene must be reasonable. Or their immune systems eat nails for dinner.
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#20 Posted : 27 July 2009 18:04:00(UTC)
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Posted By Ian Blenkharn Yes, a Health & Safety failure indeed. A failure to manage such basic hygiene issues is just that, though those paid to manage such issues may seek to put the blame elsewhere just to be on the safe side - pun intended! I am just about to publish information concerning hygiene standards in a clinical waste treatment facility. Glove use and hand hygiene was appalling, with gloves and clothing liberally splashed with blood from inadequately packaged wastes occurring in almost 100% of staff within 4 hours. There was a predictable desire to blame the waste producers, but that didn't adequately paint the whole picture. Despite being aware of the particular risks of infection, staff were observed to handle wastes without any gloves, and at other times to have a tea break or ciggie break without bothering to remove those gloves. Using a forensic technique to detect latent blood staining, there was blood to be found everywhere. On door handles and push plates, on the taps, soap dispensers, bowl and towel holders of the hand washing facilities, and on furniture items including the arms of chairs and table tops in the canteen area. Even on the handle of the jug kettle in teh kitchen! And yes, various infections had been documented among this cohort of workers, though fortunately and despite a high incidence of sharps injury and other blood and body fluid exposures no seroconversions, so far! For drivers collecting wastes from hospitals, the situation was very similar. Hand hygiene was almost non-existent. Blood was present on the internal and external door handles of the cab, and on the steering wheel of most vehicles studied. On-board washing facilities were non-existent, with staff relying on public ally accessible facilities while on the road. For this group, as for those collecting domestic refuse, the big problem was glove use and hand hygiene. Gloves were usually removed after handling wastes (though not always), and then carried by hand to be stored in the vehicle cab. Doh! With 6 or more hours on the road, meal breaks were inevitably taken in the cab. Yummy.
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#21 Posted : 27 July 2009 18:23:00(UTC)
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Posted By Raymond Rapp Personally, I will be glad when the whole populous gets the damn flu, then we won't have to suffer threads like this again - sneeze. No offence meant.
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#22 Posted : 27 July 2009 19:51:00(UTC)
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Posted By Phil Rose Dave - surely you hit the nail on the head in your first sentence. This is true nit picking over semantics. I am sorry but the use of the word 'live' by Swis will not have made any material difference whatsoever to the meaning or ultimate interpretation of his post to anyone; including a virologist or similar. No one would have gone away from this post any the worse off for the use of the word 'live' in relation to describing a virus. If the latest terminology for a killed virus (I assume that for it to be described as being killed in the first place, virologists must have previously thought of it as 'live') is 'inactivated, then perhaps we should hereafter describe viruses that were previously described as 'live' as 'activated' instead. Lets be sensible!!!
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#23 Posted : 28 July 2009 08:00:00(UTC)
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Posted By Exdeeps Morning, For my part, I think Dave Merchants input was very interesting and the point about "live" viruses etc was something that I was not aware of and will quietly look out for in future - not so I can be picky, just because I now know a bit more on the subject.... The problem with the English language is the very fact that whilst one person is trying to be precise someone else sees a pedant - as someone else has already said, it's a case of "eats, shoots and leaves" (Should I take the comma out?) Keep it up Dave, precision is important, Cheers, Jim
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#24 Posted : 28 July 2009 09:37:00(UTC)
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Posted By Swis The issue of viruses classified as micro-organisms is a debatable topic. Most (and I must emphasis on the word MOST) microbiologist(virologists) classify viruses as micro-organisms, however some believe it otherwise. So it depends in which group do you belong to hence the use of word 'live'. I refer to Dave’s commit in response to his first post; “effectively zero given the dilution factor and natural deterioration of the H1N1 viral envelope when exposed to air, UV light, the chemical soup of landfill sites, etc.; eventually destroying it.” (doesn’t that applicable to viruses on hands) Similar response has been portrayed by Ian; “If rodents or birds or insects etc could access infective materials the amount they might carry is small and the likelihood of onward exposure is surely small”. (doesn’t that apply in terms of hand contaminated with virus) Now, it’s quite ironic that both of the professionals don’t admit to the fact that transmission of flu through hands is negligible but the in their own post, they do accept that virus’s potency to cause disease gets less due to dilution factors and exposure to external environment etc(without host cell). Flu virus have a very limited ‘life’ span without a host cell (ranging from seconds – couple of hours), depending on the type of surface. Furthermore, certain micro-organisms only tend to cause a disease in certain species. So its not necessary that micro-organism which causes disease to humans will also the disease to animals, or vice versa. In regards to poor statistical data regarding landfill site and transmission of viral infections, the fact is very clear…. There’s lack of evidence to support the fact that viral infections (except foodborne infections) can spread wihout ‘direct’ exposure …. Surely the studies will follow to landfill sites, should such evidence appears.
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#25 Posted : 28 July 2009 10:13:00(UTC)
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Posted By Dave Merchant Swis - please don't try and quote me out of context to fit your arguments. You clearly have an agenda of some form, and know I don't agree with it, so let's leave it there. Barrie - in answer to the ability of H1N1 to sustain a reservoir within feral rodents, the answer at this time is no. Although we can infect lab mice with H1N1 and several other human influenza viruses, it's because they have a specific gene locus (Mx1) that's different in wild populations (which are effectively immune to H1N1 and H5N1 in practical terms). H1N1 is mutating in an interesting way at the moment, and in theory it could reform the surface receptors so it's able to bind to rat cells, however it's very unlikely to get the chance to exploit that mutation as it's not prevalent in the population - to start "rat flu", a patient with that specific random viral mutation would have transfer it to a rat, which then lived long enough to sneeze on a bunch of its mates. They do sneeze, but not very far. As to me being picky - 'tis what I do. It's a good day if nobody I meet likes me, but neither do they pay me for being agreeable ;-P
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#26 Posted : 28 July 2009 10:32:00(UTC)
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Posted By Ian Blenkharn Swis My last comment - though I doubt it will be yours. It's becoming far too tedious. The issue of transmissibility via hands is one of practicality and cannot be dismissed as you seek to do, in the face of worldwide consensus expert opinion, on hard surface survival studies. To do those studies, we put a fixed amount of infective virus on a hard surface and sample at regular intervals to determine the rate of loss of viability. But on the issue of transmissibility via hard surfaces and hands it is important to consider the reality of deposition - one or more infected individuals constantly shedding virus with respiratory secretions via coughs and sneezes. So on those hard surfaces, though virus inactivation will occur quite rapidly, the deposition of infective virus can be frequent and regular. We are concerned with that infective virus most recently deposited, that contaminates out fingers and can cause infection when touching nose, mouth or eyes. If you can assure me that your chosen hard surface was contaminated with virus only yesterday I would be reasonably happy, but you can't do that. (Incidentally, that is the scenario of the landfill site, where deposited material is not fresh and though it is topped up regularly, that newer material is also not fresh). You fall into a rather naive trap of considering contamination that occurs at one moment in time, and does not recur thereafter. In that case, I might reluctantly agree with you, though your wild extrapolation from that point onward reduces your case to a point of naivety. Surfaces may be heavily and repeatedly contaminated and at least some of the virus load will be fresh and infective. By contrast, you assume that whatever we might touch was deposited so long ago that it must be non-infective, or dead, or non-replicable, or whatever. That is where you go so badly wrong, by taking a single in vitro observation and wildly extrapolating without thinking about the reality of trnsmission routes.
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#27 Posted : 28 July 2009 11:11:00(UTC)
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Posted By Swis Dave - I have no hidden agenda whatsoever, however I do question the effectiveness of any control measure introduced on my workplace. (just to avoid the elf’n’safety news) - Furthermore, regarding infection in different species, I have conveyed the very same message in simple language without going into scientific jargon… (my previous post/your last post) Ian - I think you are misunderstanding my point of view here. As you said earlier; “You fall into a rather naive trap of considering contamination that occurs at one moment in time, and does not recur thereafter. In that case, I might reluctantly agree with you, though your wild extrapolation from that point onward reduces your case to a point of naivety. Surfaces may be heavily and repeatedly contaminated and at least some of the virus load will be fresh and infective.” We know that flu virus can only remain active/live for a couple of mins on human hands, hence becomes inactive/dead thereafter. And as the studies have mentioned also that we (humans) are in a habit of constantly touching our faces. Now how would washing the hands will prevent us getting this flu? How often should we wash hands at our workplace. Lets say that I washing my hands thoroughly with a sinister and dry them properly. I go back to work soon after.. I may have caught the virus on my hands again… the washing-up facilities are approximately 5 mins walk away from my place of work.. Would there be any point going for a hand wash, realising that by the time I reach there virus will be inactive/dead anyway? (I’m only discussing the washing hands as a precaution to avoid flu – not for other hygiene reasons – which are highly important)
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#28 Posted : 28 July 2009 11:40:00(UTC)
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Posted By Dave Merchant Hand-washing for the person with the infection is the most important factor, as they're the ones replenishing all your surfaces, and I agree if they don't bother to take any precautions there's little hope for the rest of us to keep up. If a patient walks over and shoves his fingers up my nose, I'm stuffed in more ways than one. For everyone else, washing hands is advised for two reasons aside from the direct effect - firstly, they may be pre-symptomatic patients themselves, and secondly it helps reinforce the memory that surfaces present a risk. In hospitals we know that people who keep getting told to wash their hands think more about stuff like grabbing the handle of the bathroom door, picking stuff off the floor, etc., but just giving them masks means they have no such aversion response. Having said that there will be cases where people transfer virus to their face between washes, and I'm not saying people should live with their hands in a bucket - that's why we're not claiming that any of these preventative measures will stop the pandemic. Washing hands before eating/drinking/handling food or food containers/touching your baby will of course help, and if you're bothered about door handles and shopping trolleys, carry a bottle of gel. Premises owners are advised to increase cleaning cycles but there's no need to steam-clean your furniture - the goal is to minimise deposition so a basic level of caution from the rest of us will suffice, but if your office is dripping with snot from every square inch, I for one will be staying in the car park ;) The point is being worried about the door handle makes you less likely to grab it then immediately pick your nose, despite it being a semi-conscious effect, and the combination of disinfection and contact aversion is what we're after. Picking your nose 20 minutes later is fine, provided you've not touched anything else contaminated, so it's about thinking which surfaces are likely to be shared (bathroom doors, lift buttons, etc) and which not (your keyboard, bacon butty, etc.) As Ian's man with the fragrant bacon butty needs to remember - it's not the muck you can see which kills you, it's the muck on the muck you can't see.
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#29 Posted : 28 July 2009 13:20:00(UTC)
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Posted By Rod D Guys When I was in the Army I use to go on "Live" Firing Exercises. Debate? Rod
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#30 Posted : 28 July 2009 13:35:00(UTC)
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Posted By martinw Dead right.
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