Air Conditioning

Russell Johnson from Norwich in Norfolk has been a meteorologist since 1949, retiring in 1989 due to MS. After 20 years of study, he has found that high humidity and dew point temperature often have a bad effect on MS.

I was diagnosed with MS in 1981 while I was in Borneo. The climate there is always warm, sultry and humid with high dew point temperatures. I began to notice that my MS symptoms changed when I was in or out of an air conditioned room.

Then a few years later I went to work in the United Arab Emirates where the summer and autumn are hot and humid, but the winter months more cool and dry. Here, it became apparent that my MS symptoms varied markedly according to the humidity and dew point temperatures. When I came back to the UK in 1986 I continued to investigate the link between humidity, dew point temperatures and MS. My studies were based on myself, and asking dozens of other people with MS who all had the same experience.

What is relative humidity?

Relative humidity is the percentage degree of saturation and measures the amount of water vapour in the air, compared to the maximum that could be contained by the air at the same temperature.

What is dew point temperature?

If you have a parcel of moist air and then cool it until it is saturated and produces water droplets (like the water droplets sometimes seen covering grass on a summer morning), the temperature at which this occurs is called the dew point temperature.

• The relative humidity and dew point temperatures are available from any Weather Centre or the Meteorological Office.
• In the USA, the dew point temperatures are broadcast every day on TV. Yet it is almost unknown here. The UK Meteorological Office used to broadcast dew point temperatures many years ago but don't do this now.

Air Conditioning Is The Answer

My main help in alleviating my MS symptoms is air conditioning The same applies to others too. Personally, I have AMCOR portables (models 2000M and 12000R) - one in my bedroom and one in the lounge. I switch then on when the dew point temperature gets above 10°C (50°F).

These are my tips to beat humidity:

• Have air conditioning in your house - at least in one room.
• Always have air conditioning in your car.
• Wherever possible, shop in stores with air conditioning.
• If you haven't got air conditioning and the air outside is warm and sultry, do not open all the doors and windows. Only leave a small window ajar. The air inside a house is normally drier than outside, so try and keep it that way.

Where You Live and Go On Holiday

If you choose to live in the west of the UK, always remember that the prevailing wind is from the South West. Usually it is mild and damp, and sometimes during the summer months very humid weather brings high dew point temperatures, which can be bad for those with MS. As this air mass usually gets drier on crossing hills or mountains, it is better to be on the north east side of high ground, if you live in this area.

If you live in the east of the UK, it is best to live near the coast where you will usually get the advantage of summer sea breezes, which frequently lower the dew point temperatures during the day. Luckily, I have nearly always been based in the Norwich area, which is favourable for MS. Otherwise I would have moved to a suitable climate for MS.

If you live in the South, North or Midlands, that's fine, but it's best if you can live on the leeside of a hill, as it's drier.

When going on holiday, avoid places with very high sea temperatures. Try to stay in places sheltered from warm winds on the lee side of high ground.

Humid Places To Avoid

Anywhere with a high dew point temperature

• Far East
• Middle East
• Southern states of USA

Least Humid Places

Anywhere with a low dew point temperature.

• Anywhere with a cool climate.
• Anywhere next to cool sea all year round.
• A warm dry climate, such as some parts of Europe, Africa, South America, Russia and China.

Some Facts About Air Conditioners

Portable air conditioners will only work with rooms that either have:

• Windows that are open at least 6 inches (15cm)
• A suspended ceiling with a ceiling void of at least 16 inches (40cm) above.
• Any other means of ducting out the hot air through the tumble drier type hose on the back of the unit.

Fixed Systems

For domestic use, these are usually fixed to an exterior wall. They are more expensive than a portable system due to the installation costs. However, fixed units are quieter, more efficient, and look neater as there is no visible hose. To fit one unit in an average size bedroom and one in a lounge, expect to pay around £3000 + VAT.

5 things you didn't know about air conditioning

• Humans have been trying to cool air since Roman times when emperors ordered snow to be brought down from the mountains to cool their gardens.

• Invented in 1902 by unsung American inventor Willis Haviland Carrier.

• American cinemas used air conditioning to attract audiences in summer. The early systems had vents in the floor and moviegoers sometimes had to wrap their legs in newspaper to fend off the cold.

• Gore Vidal said: "I date the birth of the empire to the invention of air conditioning." Before air conditioning, Washington was deserted in summer.

• Today, 83% of US homes and 98% of US cars have air conditioning.

Further Information

The Air Conditioning Company
Summit House
40 Highgate West Hill
London W6 6LS
Tel 020 8340-8000
E-Mail: info@airconco.com
Website: www.airconco.com

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