If you suffer from hay fever you’ll know what a blessing it is to be able to sit indoors in spring and summer with all the windows and doors shut, keeping the airborne pollen out while still being kept cool and comfortable. Then, in winter, you don’t keep the windows open as you have central heating and it would just let the heat out. In fact, you never need have fresh air in your home again!

And that’s where the problems start.

Air con and central heating can really dry out the air in a house and a lack of moisture in the air can lead to dehydration. You might ask “So what? I’ll just have another glass of water and I’m good!”

But it’s not only you who’s affected by dry air. You might also see:

• Wood shrink and warp meaning that varnish or paintwork can crack and chip, joints become loose, doors and windows start to stick or let drafts in

• Plants drying out and looking unhealthy or even dying because they need watering so much more frequently

• House dust becoming an ever more common problem. Dry air lets dust move about in the air more than moist air does. This means that it can get everywhere more easily making cleaning a harder job than it needs be.

Air conditioning units can become very expensive; if they are set too high or there’s a window open elsewhere in the home, an air conditioner will keep on working until the temperature is reached.

If your air conditioner is the wrong size it won’t work properly, insomuch as one that is too small won’t cool the whole home, just a room or at best a floor in a house while too big a unit will be difficult to control adequately, blasting out too much cold air and becoming a nuisance to adjust correctly.

Another problem that people experience is a health one too, the dry air makes eyes, noses and throats dry, even if you do increase the amount of water you drink. Skin can get dry and scaly while your hair becomes dull and brittle. And these symptoms aren’t restricted to humans, pets will suffer in much the same way, tropical birds which evolved in a particularly humid climate will become especially vulnerable to the effects of dry air.

So what’s the solution?

You could go without your air con. But that means overheating in the summer, a return to the stung eyes, streaming nose and coughing fits of a summer suffering from hay fever. Not really much of a health benefit at all.

The other answer is to consider investing in a humidifier. Now, the idea of having one machine to cool and dry the air and another to put the moisture back in might seem a bit like wearing a belt and braces but all things considered it makes sound sense. Dry air is more of a side effect than an intentional product of the air conditioner and so fixing the problem is something that should be considered. Not only does it make the air feel fresher, it prevents all of the problems listed above, although if things like furniture or antiques are warped it can’t fix them although it can prevent them from getting worse.

Of course they’re not without drawbacks of their own, again, the wrong size of humidifier will prove inefficient, too small and it won’t be able to deal with the space it’s supposed to be humidifying, too big and you run the risk of creating a whole different set of problems with damp and condensation.

Even The Smallest Elephants Find Getting Airborne A Struggle

The European Union is striving to limit the amount of gases which are released into the air, both in terms of variety and volume. The Union has 27 member states not including the UK and together they produce 4,177,817.86 thousand metric tonnes of carbon dioxide each year. That’s the equivalent of 596,831,123 African bull elephants charging through the skies of Europe every year (1,635,153 elephants every single day) . Even if Dumbo could fly those statistics would still be impossible since that amount of carbon dioxide alone (therefore not including all other forms of airborne pollutant) produced in Europe in a year weighs more than a thousand times as much as the weight of all the elephants alive on Earth today.

Europe’s contribution is 14.04% of the total carbon dioxide released into the air each year, the US produces 18.11% of the global airborne CO2 per annum and China almost a quarter, their industry, domestic and vehicle use of fuel produces 7,031,916,000 tonnes of carbon dioxide every year and as their economy changes ever more from agriculture and small industry to heavily fossil dependent energy consumption their contribution to the production of greenhouse gases is exploding. Put together those three market sectors alone cause more than 56% of the world’s gaseous carbon dioxide.

Fortunately a huge part of this carbon dioxide is take up again in plant growth which in turn releases oxygen into the atmosphere and stores carbon in its very structure. A natural carbon capture and storage programme if you will. However, there is still an excess of CO2 which stays in the atmosphere and it is this, among other gaseous and particular pollutants which cause global warming. If you also factor in the millions of litres of methane that animals produce and the gases and ash that volcanoes create then clearly ‘fresh’ air is far from free of all kinds of pollutants and irritants. Add tonne upon tonne of pollen in the summertime to all this and you’ll realise it’s almost a luxury that we’re able to see our hands in front of our faces thanks to all the stuff that’s in the air!

But What Can Any Of Us Do About It?

On the small scale every-one knows that it is necessary for us all to reduce our carbon footprint, share car journeys, avoid unnecessary flight, turn our thermostats down a little and insulate a lot as well as recycling everything that won’t compost.

That’s Fine Dealing With CO2 And Landfill, Is It Possible To Do Anything About The Atmosphere In The Home?

A humidifier will help keep dust down, literally, during the dry parts of the year. Summer is obviously dry but indoors winter can be too, with central heating turned on (even at a degree or two below normal) it can leave the air dry and therefore dust can blow up and get into convection currents more easily. A humidifier makes this far less likely as dust finds it harder to move about in a moist atmosphere.

But keeping dust down is only half of the story. If you suffer from hay fever or other allergies to particulates such as pet dander an air purifier might be a better long term answer. Air purifiers use a variety of filtration methods to keep air at a quality you can enjoy. And they run at such low power levels that they consume less energy than a domestic lightbulb, meaning that they contribute negligibly to your carbon footprint. So effective are they that they not only clean pollen and dust from the air they can even control the passage of airborne viruses while filters using carbon can clear bad odours and theoretically absorb toxic gases. However, if you think you smell gas you should vacate the building immediately and call the National Grid on 0800 111 999.

Televisions
Plasma TVs gulp down energy like a drowning fish, as much as triple the consumption of an LCD TV and even LCD TVs use up far more than the old fashioned cathode ray tube TVs that it seems so hard to get a hold of any longer. If you haven’t upgraded for digital, again it’s s good idea to look into getting a good, energy efficiency rated TV set and remember to switch it off properly when you’ve finished watching. In fact, running your home entertainment from a distribution board which you time to go off when the house is empty would save a considerable amount of money. Something to think about.
Air Purifiers, Coolers And Dehumidifiers
As mentioned above, the health benefits of these appliances speak for themselves but that doesn’t defeat the fact that they do use a considerable amount of energy to run. If you have one now or are thinking of investing in one in the future there are a few point to remember to keep running costs down.
Get one which is rated for energy efficiency, most appliances are these days and to keep it in good running order remember to have it serviced as per the manufacturers instructions.
Make sure it’s appropriate for the space. If it’s too small you’ll need to keep it running flat out all day to keep the rooms comfortable. Too big and it’s simply inefficient to run it at all.
Keep windows and doors shut if you’re trying to keep a building cool and don’t bother running the dehumidifier while you’re ventilating if you have a damp problem. People who insist on opening windows when you’re running purifiers and coolers are just letting dirty, warm air in and cool, clean air out.
Your Turn
Now over to you. You can run your own tests using a home energy monitor, some councils make them available to borrow from your local library. They’re not expensive but if your friends family and neighbours are interested in keeping the costs of their utilities down it might be worth clubbing together to identify where the biggest power drains are and think of a way to fix them.

Wimbledon and Humidity Woes

Wimbledon fans have been hoping for glorious sunshine to accompany 2011’s tennis tournament which began last Monday. Instead the weather has been largely poor with the ever-promised UK heat wave never quite coming to fruition. Scorching temperatures have only occurred for short moments and at random intervals during this year’s event thus far.

But did you know that the weather – or more specifically; the level of humidity – can have an effect on how a game of tennis pans out?

It has been scientifically proven that high humidity can increase the mass of tennis balls and this can affect how high a ball will bounce after impact with the ground. In addition to this, humidity affects the ways in which racket strings behave.

In fact it was reported by The Telegraph last week that Britain’s current number 1 (and also ranking as the world’s 4^th best player) Andy Murray’s first game against Daniel Gimeno-Traver was affected by a change to the levels of humidity after the roof of the court was closed due to bad weather.

“[The roof] definitely slows the court down”, commented Murray after the match.

The Science Explained

The most common racket strings are made from “gut” (read as; animal intestine) and are usually provided with a coating in order to reduce the material’s tendency to unravel whenever it becomes humid or wet (such coatings have different levels of success). Many varieties of racket string absorb moisture caused by humid conditions and this can soften and loosen the tension of racket beds. The softness of a string bed can indicate how much moisture has been absorbed (i.e. the softer it is, the more moisture likely absorbed).

Beds with the wrong or an inconsistent tension can affect the speed and spin of the tennis ball after impact.

Mark Kidger – an aerospace engineer who has written several books including The Physics of Cricket – argued that it is the tennis ball (and not the racket) which is central to the changes in play resulting from increased humidity.

“The roof traps the humidity inside the court [...] You’ve got 15,000 people inside, all breathing and sweating away, and then there is the moist surface of the grass, which will be releasing more water vapour into the atmosphere”, began Kidger, as he explained his theory to the Telegraph Sport.

“The ball will suck in some of that water vapour and so become a little bit heavier and slower, both through the air and especially off the court. When it bounces, it will sit up nicely to be hit rather than rushing through as normal”, Kidger claimed.

When the All England Club had the roof installed back in 2009, nine air cooling machine were concurrently installed which switch on whenever the rood is closed. Although these machines pump 143,000 litres of chilled air through the arena every second, this is clearly not enough to deal with the high moisture levels.

Perhaps the club should invest in a colossal dehumidifier (or two hundred!) to deal with the increased humidity cause by roof closings. Players of Wimbledon and the rest of us will inevitably face more bad weather before the tournament comes to its end!

The pride in her newly decorated W/C was short lived however as one day in March when she was perched upon her porcelain throne, she looked up and noticed that the mould had returned. Pressing work related matters meant that she couldn’t address the issue right away and a week later, the problem had spread considerably.

I had to make it clear to her that a wipe down and yet another lawyer of paint was not going to defeat the festering beast! It was time for her to address the actual cause of these spores.

Mould thrives in moist conditions and the bathroom’s location – between two dark basement bedrooms – means that the room not only lacks any built in ventilation but also lacks direct sunlight, which contains UV rays which can end the spawning of mould spores. Although there was little she could do to add sun beams to the room, I advised her that a dehumidifier was the obvious solution for preventing the high moisture levels in the room’s atmosphere.

Soon after, my friend purchased herself a wall mountable dehumidifier from us in order to keep moisture levels below 60% – the magic number that gives birth to mould. Disinfecting the mould laden area regularly and turning the unit on for an hour during/after running the shower has seen a considerable decrease in fungal formation but needless to say she is holding off on repainting the area for the time being until she is sure she has won the spore war!

While I love being able to wear summer clothes and spend more time outside, when temperatures in Britain begin to soar everyday life does become uncomfortable. If you own a car with no air con you are drenched in sweat by the time you get home from work.  Sleeping is difficult, and it becomes a necessity to take multiple showers in a day if you don’t wish to end up smelling like stig of the dump!

Many people blame the heat, ‘it’s too hot’ is a common compliant we hear very often, but do you ever hear people moaning about the humidity? While heat is easy to gauge as we have been conditioned to notice changes in the ambient temperature, I would guess that we’re not so perceptive about how humid it is. Humidity contributes just as much to how hot it ‘feels’ as temperature does.  No need to panic though!  There are products on the market which allow you to control the humidity of your immediate environment at least.

Dehumidifiers are a great way to make your scorching summer that bit easier to deal with. While desk fans and air conditioning units can help control the temperature of the room, a dehumidifier will absorb moisture and take away an annoyance you didn’t even know was there. They available in a wide range of sizes to suit cupboards, lounges or large offices.   A simple desk fan on its own may not cut the mustard on a particularly stifling mid-summer afternoon, but if you can’t stand the humidity, trying teaming your fans up with a dehumidifier or investing in air conditioning instead.

All dehumidifiers use mechanical energy to move air, so they do tend to make a certain amount of noise that comes from the compressor mainly in refrigerant models and even desiccant units use fans to draw in air.   However the latest models are certainly far quieter than their predecessors.  Many top end models also have a frost protection feature using a hot gas system to defrost the internal cooling coils so they can be used in cold weather, however their efficiency can be diminished at very low temperatures.

For very small spaces like wardrobes, cupboards, sheds, caravans, boats or garages, a desiccant moisture absorber should be sufficient, especially if these locations don’t have a power supply.   The Superdry moisture absorber for example contains desiccant that will absorb up to 1.5 litres of water from the atmosphere for up to eight weeks at a time.

Larger rooms may require a dehumidifier that can extract around 20 to 40 litres of water every day, especially during very humid days. If smaller rooms need to be dehumidified, half that capacity should be sufficient so a product like the GD10L 10 Litre dehumidifier would be perfect.  This compact and economic unit has a continuous drain option so a hose could be fitted to take the water directly to a drain, thus by-passing the automatic shut off many of these more compact units have when their relatively small tank is full.

Tank size is definitely a consideration to take into account. The dripping water from a dehumidifier is collected in a tank which has to be emptied periodically. Obviously, the smaller the tank, the more frequently it needs emptying. Some compact units can be surprisingly efficient with powerful little dehumidifiers that can remove up to 20 litres of moisture every 24 hours.  That’s adequate for a 3-4 bedroom house or a humid cellar or garage.  These units incorporate an integral water container or can be connected to a drain for continuous discharge.

If you’re in a band or an orchestra and have musical instruments in the house, you’ll be aware of how quickly they can “spontaneously” go out of tune.   That’s especially the case if you live or perform in a very dry or arid environment.   There are humidifiers specially made for instrument cases and some humidifiers may actually attach to or fit in the instrument, like a humidifier that fits in the soundhole of a guitar or in the f-hole of a violin.   If you live in consistently moist or damp environments, or perform in halls that have that familiar “musty” odour, you may want to consider some way to dehumidify the instrument.  That’s usually achieved by adding a desiccant, such as silica-gel or dry clay granules inside the instrument case (never inside the instrument itself).

If you and your instrument spend a lot of time in one particular location, like a practice room or a recording studio for example, then it’s probably worth looking at systems that will humidify or dehumidify the entire environment in which you perform.  That’s particularly helpful if, as is often the case, the studios, rehearsal rooms or live venues are in basements or barely maintained village halls.  If you want to find out if you need a humidifier, buy a thermohygrometer.  The ideal humidity for most normal situations and to maintain your instrument in perfect tune is between 40-60% relative humidity. If the thermohygrometer reads below this you probably need a humidifier. If it reads above this you may need a dehumidifier.  Dry air in these places can affect more than just your instrument.   Breathing in dry air can lead to fatigue, tiredness and reduced concentration levels as well as an increased susceptibility to colds and respiratory tract complaints.

Even before you get your hands on the instrument, there are equally sound reasons to control the humidity in the music store too.  Guitar woods are no longer plentiful and inexpensive and customers are increasingly asking where the wood came from and what is being done to conserve it.  Most factories control their climate during manufacture and most instrument owners will keep their guitars or whatever protected in cases. It’s the retail music store that’s potentially the worst environment that a guitar or other instrument will ever experience at a time when you want them in first rate condition in order to sell them!  Controlled humidity throughout the shop will benefit all guitars for example, not just acoustics.  Most guitar manufacturers are also becoming very strict about returns they will take responsibility for, and are insisting on the use of humidifiers or dehumidifiers as appropriate in their retail, franchised or independent outlets.

Now, recent studies and reviews of previous work  suggest that maintaining an indoor  Relative Humidity (RH) level between 40-60% can not only relieve cold and flu symptoms, it can actually help kill flu viruses on surfaces and in the air if used with other measures.

Research that studied the correlation between why the influenza season peaks in the winter months when air temperature and RH levels are so low concluded that the survival of influenza germs can be reduced significantly by using humidifiers to create RH levels of at least 40%.  Using mechanically atomised influenza virus samples released as an aerosol to infect chicken eggs or egg membranes, studies consistently show that influenza survives far better at low RH levels.    Although not as extensively studied as the effects of RH on aerosol survival, studies on the effects of RH on influenza survival on hard surfaces also showed a similar correlation.  The data across several studies is remarkably consistent.  Influenza germ survival is greatly reduced in environments with an RH of approximately 40 -60%.

Of course, this only reduces influenza germ survival rates and there is still no cure for the common cold. There are things you can do to alleviate any symptoms and using a humidifier is definitely one of them. Maintaining the right amount of moisture in your home can help to soothe sore throats and allow you to breathe better and sleep more comfortably.   Even when the whole family is healthy, proper humidity levels in the home can relieve other winter symptoms caused by cold, dry winter air, such as a dry nose, a dry throat, and dry eyes.

That’s why more people are looking to rent a property and more potential purchasers are seeking the still relatively easy to get buy to let mortgages to rent out property. In truth, there are many advantages to renting.  There’s more rental stock available and monthly rentals, even for larger properties, are not much more than the equivalent mortgage would be (if you could get one!). And of course, from a tenant’s point of view, maintenance is someone else’s responsibility.

That responsibility falls on the landlord or the managing agent, and often with older properties one issue that constantly crops up is the question of mold.  Tenants can request a mold inspection particularly if there appears to be health implications.  Even if the room or property has no visible signs of mold, it could be that there’s a damp basement or if it’s a block of flats it may be other properties affecting the rest. Landlords have a duty to maintain rental properties at a certain standard and if a landlord does not fix the problem, the tenant has the right to withhold rent and pay for the work to be carried out while still withholding rental payments.

Installing a dehumidifier will avoid this issue completely. The ideal humidity for most normal situations is reckoned to lie between 40%-60% relative humidity. If an instrument called a  thermohygrometer reads above this you may need a dehumidifier to reduce the level of humidity in the air and so restrict mould and mildew growth as well as dust mites.  This simple measure will prevent damage to the fabric of the building and furnishings a well as avoiding various adverse healths affects and reassure tenants into the bargain.

Her supposed ability (dubbed Street Light Interference Syndrome – or SLI) has earned her international fame.  In Japan, she has been likened to heroines from cult Manga comics and she has been compared to characters from the BBC2 show “Heroes”.  For a woman who believes she interferes with electrical equipment, Debbie has chosen a risky job as a pathology support officer at the Royal Sussex County Hospital in Brighton, although to date none of the hospital equipment seems to have been affected.
So is SLI a genuine paranormal phenomenon or merely coincidence?

In true Derren Brown expose fashion, we present a possible and plausible explanation. Apart from temperature and air purity, the third important factor in the maintenance of an ideal room climate is the moisture content of the air.  With central heating and double glazing, you can experience excessively dry air indoors. The consequences of dry air are severe.  It can lead to discomfort, tiredness, and sickness as well as greater susceptibility to colds and increased levels of dust created by the thermal currents from radiators.

However, one other consequence of very dry air is increased levels of static electricity. Large data centres for example have banks of sensitive electronic equipment producing huge quantities of heat and need humidifiers to stabilize the fluctuation of relative humidity (RH). Low humidity can lead to excess static electricity and electrostatic discharge (ESD) that can fatally damage components. Even without ESD, fluctuations in humidity can cause circuit boards to expand and contract, damaging the circuitry.  What’s true in an industrial application can also be true in the home.

Higher humidity reduces static problems, so what Debbie needs is a decent humidifier to stop her contact ESD.  It’s likely that her hospital workplace already has a humidity controlled environment, which could be why she doesn’t fritz the medical gear.    On the other hand of course, Debbie could be a genuine Magneto in the making, in which case we would recommend a dehumidifier if she ever wants to boost her powers!

We recently extended our house and installed an oak floor in the new open plan area, some 48m square.  We found within a month or so, that the floor was expanding due to moisture and that the oak boards were ‘cupping’ which was very disappointing.

We were recommended by the ‘Air and Water Centre’ to purchase a dehumidifier in order to remove any excess moisture originating from the new plaster walls and because we have our kitchen in this area which is also a source of moisture.

I am extremely pleased with the results, as the floor boards have now shrunk back to their original shape.

The dehumidifier has performed very well, removing at least 10 litres of moisture, or a full tank every few days. I like the fact that it has a big tank and has automatic set-point controls to regulate operation. It also expels warm air which acts as a small heater and keeps that whole are quite warm.

I would have no hesitation in recommending this dehumidifier.

The room is small, so the compact size of this unit is ideal. It’s very quiet and will fully dry a load of washing overnight.

When you look at the small print for most dehumidifiers the outputs they claim aren’t real as they are tested at high temperatures and humidities. When they are used in actual life they don’t remove anything like what they claim.

The Ruby works so well as it doesn’t matter whether its used in a cold or a hot room.  It also gives off a bit of heat which helps in my cold spare room too.

Excellent dehum. Thoroughly recommend.

Oh.. and it’s light too. Easy to move around.

A desiccant dehumidifier contains a material that absorbs the moisture directly from the air and then releases it into a tank when it is warmed.

A compressor driven dehumidifier is the more traditional type and works by creating a cold surface upon which moisture for the air is condensed – just as moisture forms on a cold glass on a hot day. This condensation then runs from the cold surface in the dehumidifier into a water tank at the base of the unit.

Both types work very well but both have disadvatages and advantages. As the desiccant dehum doesn’t need to contain a compressor they are normally very light and easy to handle, whereas compressor driven models tend to be quite heavy. However, as desiccant models need to produce heat to extract the moisture from the air they require more power to run than a compressor driven model so can have higher running costs. They also tend to be more expensive to buy initally.

A major advantage of using a desiccant dehumidifier is that they are very effective at low temperatures. A compressor driven dehumidifier is less effective in a cold room as cold air doesn’t condense as easily on a cold surface as warm air does. This means that in warm areas above 20 degrees compressor driven models are very effective but as the temperature drops so does their ability to remove lots of water from the air. As the desiccant model isn’t affected by temperature, it can extract roughly the same amount of moisture at 5 degrees as it can at 15. If you are looking to dehumify a garage or shed then desiccant is definitely the way to go.

However, neither type will function in freezing conditions. Some compressor driven models incorporate a “Hot-gas defrost” feature. This doesn’t mean they can dehumidify in freezing temperatures, rather they defrost the ice that forms internally at colder temperatures more quickly so perform better than other compressor driven models without this feature. Even hot-gas defrost models can’t compete with desiccants at very low temperatures though.

Lastly, as the compressor driven model requires refrigerant to function, it could be said that desiccants are the more environmentally friendly option, as they require none. Although, it could be argued that as desiccants consume more energy when operating, the benefit of not using refrigerant gas is outweighed by the increased carbon footprint it has over its lifetime.