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WHO Isopropyl FormulaQuote:
Originally Posted by FenceFurniture
• Isopropyl alcohol (99.8% concentration) 75% (v/v),
• Glycerol (98% concentration) 1.45% (v/v),
• Hydrogen peroxide (3% concentration) 0.125% (v/v)
• H2O to make up to 100% (v/v)
Cooling the water may reduce the evaporation of the alcohol until bottled.
This is a befuddling story.....in the middle of what may be the worst unemployment since the depression.
I know of this second-hand, but at very close range, and it has happened over the last week.
A person has a full-time tenured position, at ~$150,000pa, and has been in the job for around 18 months. They have a PhD, but it is not strictly in the field of the job title. In other words, this is no dummy. They are surrounded by similarly qualified, highly educated people. They have been recently unhappy about being undermined, both from above and below, with the underling apparently engaging in shouting during a Zoom meeting last Friday. The meeting was called by the person in question so as to resolve the difficulty with the underling if at all possible.
Not so long ago, this person had saved the underling's skin from some other kerfuffle where they had behaved badly towards another staff member.
The person had already decided to go on 5 weeks annual leave starting from this week, and was going to consider their position in that time, which they were regarding as untenable. They were basically thinking of resigning. I had discussed this with the "second-hand" person who related the story to me, and my view of it was that to resign was lunacy in the current environment, and virtually at the end of a career (63 years old).
As it turns out, the five week leave was not used for consideration, and they submitted their resignation yesterday. :doh:
There are times when you need to stand up for yourself, and have the courage of your convictions. There are other times - extraordinary times - when it might be smarter to lay low for a while, and maybe even ride out the storm. As I said last night, the person will feel very foolish indeed if the underling is independently brought to heel if or when they are discovered to be "unsuitable" for their own job (which would seem to be the case).
Good luck finding another job....of any kind....ever.
Another early retiree in the making.
Sorry to quibble Neil, but formulae can be critical. According to the WHO Brew sheet that Bob posted a while back (reattached here), it should be 4% volume (actually 4.17% but...) of Hydrogen peroxide of 3% concentration (which is why I nominated 2% of 6% concentration, being much cheaper to purchase than 3%).Quote:
Originally Posted by NeilS
Peroxide and Glycerol quantities are the same for either alcohol type.
The two formulations are on the 3rd page of the PDF (nominated as page 2 of 9).
:no:Quote:
Originally Posted by rustynail
Made!
Breaking news from the NY Times:
Coronavirus Live Updates: Studies Show N.Y. Outbreak Originated in Europe - The New York Times
Do scroll down through that blog to scope some of the excellent photo-journalism from the NYT. USA PJ is the best there is.
Maybe someone can shed some light on this conundrum?
We established a while ago that the 20 seconds of hand washing is just the lathering part of the process - i.e. not including the time it takes to rinse off the lather. This is because it can take 20 seconds to denature/disrupt the lipids that protect the virus.
So what use is just wiping down hard surfaces? Surely the same metric should be applied, and all of the surface needs to have a lather on it for a full 20 seconds before a rinse wipe down? AFAIK, the lather needs to be agitated too, to completely disrupt the lipid coating - in other words each part of the surface needs to be rubbed with the lather for 20 seconds. That could take *some time*.
This is even more difficult to achieve when wiping down groceries (which I have not been doing). I have been more relying on the virus "dying" within 24 hours on cardboard, and 72 hours on plastic or steel.
20 second hand washing is with soap and water (Happy birthday to Me twice and then rinse off). Evaporative sanitiser is wipe on and leave it. According to my friend who is a grub, I mean scrub nurse.
Due to the rona virus, at work we now have to clean machinery controls at the end of each day on the machines that we were using. I generally run two or three of the saws during the day so I clean those. I spray one, walk over to the other spray that, and then a third if needed. Then I wipe down the first, second then third. I don't know what I am spraying, just some soapy stuff that the bosses missus put into a bottle for us.Quote:
Originally Posted by FenceFurniture
Thanks Ken. So presumably when they say "wipe down surfaces" that means with alcoholic sanitiser - maybe I missed that bit.
OK, Brett, let's get this right.Quote:
Originally Posted by FenceFurniture
Here are the concentrations within the individual ingredients before mixing and the recommended amounts of each at those concentrations, other than the water. The added water will bring the total amount up to give required total volume.
Attachment 471295
I should have also given those WHO mixing proportions in my reply, which would have been far more useful for anyone wanting to making up an Isopropyl batch.
Here are final concentrations of the active ingredients once all the ingredients, including the water, are added in the recommended proportions.
Attachment 471294
As I understand it, % v/v (% volume in total volume) are measures of the concentrations of the active ingredient in a solution. So, a 3% concentration of H2O2 when added in the recommended proportions (eg. 41.7 ml in a 1.0 Litre batch) will give a 0.125% by volume of active H2O2 ingredient in the total (100%) volume of batch. Those % v/v are given so the concentrations can be tested before use in WHO field operations. Not so relevant for our context.
And, yes the proportion of diluted H2O2 ingredient at 3% concentration to be added to the batch to achieve that is about 4% of the batch mix or 41.7mil in 1Litre or 417mil in 10 litres, as recommended by WHO.
And here according to WHO is the role of the H2O2.
Attachment 471296
Thanks for the quibble, Brett. I think we have that right now.
Goodo Neil. I see the (my) confusion with v/v, and I'm not even sure I looked at the "final concentrations" because I was just working off the mls/litre recommended amounts (which as you say are more useful).Quote:
Originally Posted by NeilS
This is a useful series of small graphs which easily compares "growth factors" around the world (Australia's is at the top of the article)
One coronavirus number will let us know if Australia’s outbreak is getting worse - ABC News (Australian Broadcasting Corporation)
The growth factor (by that measure) is simply today's new cases divided by the average cases over the previous 5 days. Below 1.0 is good (decreasing) above 1.0 not so good, and consistently above 1.0 means that cases are growing exponentially.
Very interesting to note that the vast majority of the countries show had their worst day in mid-March, with March 13th being the most common with 12/25 countries (and in radically different parts of the world, but most commonly in Europe)
I am mindful of Greg Ward's post (#1337), which cautioned us about attacking other nationalities and in principle I agree that it is not constructive. Indeed, our time may well be better spent solving our own issues.
However there are some things that to my mind cannot be ignored, particularly if they point towards a general trend or way of thinking. Yesterday I heard Donald Trump criticise the WHO for handling the Covid-19 situation badly and being biased towards China. As it happens I think the WHO might have done a better job at times and there appeared to be a political influence in the early days. They didn't declare an "emergency" or pandemic status soon enough, but there again we are all guilty of the benefit of hindsight. However, Trump's accusations towards this organisation, towards China and indeed his whole attitude made me see red. The full story is here on a BBC link:
Coronavirus: Trump attacks 'China-centric' WHO over global pandemic - BBC News
Now these comments are coming from the leader of a nation that had the opportunity to see what was happening in the rest of the world and benefit from their situation, but did nothing. These are comments from a nation that has now hijacked medical supplies destined for other countries (US hijacking mask shipments in rush for coronavirus protection | World news | The Guardian) in their desperate and undignified (OK there is nothing dignified about Covid-19) rush to make up for lost time and demonstrate their rich kid tactics.
But mostly it is the public comments perpetuated by Trump in the preceding months that stick in the throat. Have a look at this for the timeline and to my mind disgraceful sequence of comments culminting in the attack on the WHO (not in the calendar but reported in the link above):
Trump'''s Coronavirus Calendar
If our Australian politicians make a single slip up five years ago our media is right onto them. How is it that Trump can get away with such blatantly incorrect comments and then do such about turns and nobody is pulling him up on these inconsistencies? Sure we all make mistakes and, reputably, it is the measure of a man that can admit to these. However, in the first place Trump does not admit to them, but proceeds as if they were never said. Secondly, if the populace goes along with what he says, and I am led to believe that his popularity has not waned during this time, he is at least partially responsible for the dire straits in which the Americans find themselves: Namely, the worst affected nation in the world.
How can he have misled his nationed so disastrously?
Regards
Paul
Not quite. I understand that it takes 20 seconds to remove (break up) the grot on our hands and to get through that right down to our skin surface. We all have a fatty layer on our hands even when they look clean, otherwise we wouldn't leave fingerprints.Quote:
Originally Posted by FenceFurniture
Put more succinctly by Norman Swan, ".... handwashing with soap is probably best, because it removes the fat layer on your skin which holds the virus. But hand sanitiser is a very good runner-up."
Door handles and the like may need a bit more attention because we are more frequently transferring some of the fatty layers from our hands onto those, but again according to Norman Swan, other hard surfaces that are cleaned relatively frequently, like bench tops, can just be cleaned with a regular detergent in a regular fashion. No need to be so OCD with that!Quote:
Originally Posted by FenceFurniture
We are using the same protocol of putting whatever we can into quarantine for the recommended periods and only giving the fridge/freezer items immediate attention. A quick detergent wipe over and dry for those. Fresh produce is either cleaned immediately or before use as we would normally do.Quote:
Originally Posted by FenceFurniture
This week we had our first supermarket home delivery. That is going to be good, but introduced plastic bags (which we haven't had for well over a decade) so that has introduced another component. At this stage they have just been put as they are into quarantine before being returned at the time of the next delivery, which will be after the quarantine period has expired.
We have a similar protocol for pharmacy items.
Also had our first tele-consult with our doctor last week. That went well for the purpose of renewing scripts, although filling some of those has been a bit tricky. My asthma preventative med has become rarer than toilet paper. Suddenly all those people who have been prescribed asthma preventative medication but not bothered to keep that up until now have become zealous!
Only face to face contact this week was to get our (early) annual flu shot, the seniors one, which is a stronger brew to compensate for the weaker immune response in oldies. It's free, but we may have to get a boost later in the season depending on whether the flu makes a come back after a very slow start this year, presumably due to our collective preventive measures for Covid-19. The Doc who gave us the jabs was fully kitted out in PPE to remind us that it is on out there.