Hot chicks with mobile phones. That’s right, researchers have found that EM radiation (like that from cell phones) can ‘cook’ the embryos in chicken eggs. We sent Ty Pendlebury to find out how much our beloved boxes radiantly radiate.
ABOVE: The C-Tick denotes compliance with Australian EMC standards.
Windows and Perspex cases are here to stay. And it's a good thing too, as it's taken a bloody long time for PC manufacturers to cotton on to the idea that no one likes beige. No one.
PCs are bleeding into every room of the house, but are today's cases disgorging more than just tech into our homes? Bucketfuls of fans, increasing CPU speeds, Bluetooth and Wi-Fi transmitters are all generating radio frequency, and the prevalence of unshielded casings is only adding to this.
Since WWII, scientists have investigated the effects of radio frequency (RF) on humans, after military radio operators reported 'feeling warm' when operating their equipment.
Countless studies have followed: the effects of power lines on Tongan children; EMF emissions in the workplace; and now mobile phone emissions.
The idea that RF could be used as a weapon soon followed. In the 50s, military scientists experimented with the effects of extremely low frequency (ELF) on humans, and the potential for creating a mega 'ELF cannon'. But due to the massive amount of energy needed to create sub-audible frequencies it didn't have much of a range, and the weapon was shelved. However, another recent invention, hypersonic sound, has piqued the interest of the military once again. It uses several high-frequency beams which, when targeted at an object, becomes sound. Though it was designed as a directional, domestic device, it could also be used to focus a debilitating loud or destructive sound at targets without affecting the immediate environment.
Eric Cartman taught us that certain types of frequencies adversely affect the human body. He attempted to recreate 'brown noise', a sound causing everyone who heard it to, er, well, you get the picture. Nerves and muscles operate on very low frequency electrical impulses, and they could become confused if those frequencies were replicated.
Meanwhile, mobile technology's effects on human tissue are still a matter of hot debate. Some studies say it's safe while others say it's carcinogenic. If low frequencies and microwaves can affect the environment, and us, surely any sort of electromagnetic frequency (EMF) could have ramifications.
RF is one of two types of radiation -- non-ionising radiation -- while the other is known as ionising radiation. Radiation types in frequency up to ultraviolet (UV) rays are non-ionising, while UV radiation, X-rays, gamma rays and cosmic rays are ionising. Ionising radiation breaks carbon bonds in the molecular structure of organic cells, and that's bad, ok? Non-ionising radiation is thought by some to have little medical effects, while ionising radiation is known to have significant health effects with prolonged exposure, such as cancer.
Until Thomas Edison invented the light bulb, radiation existed only in a natural state -- during events like lightning strikes. It might sound kind of dumb and science-fiction-y, but over half of our exposure to radiation comes from decaying uranium and cosmic rays. Uranium produces Radon gas which leaches into the soil and ultimately collects inside buildings.
While the frequency of EMF seems to have an influence on its effects, the relative power output is also important and due to the inverse square law, so is a user's proximity to it.
EMF is subject to the inverse square law, which means as the distance doubles the strength of the field is reduced by a quarter.
There are two main units used when describing amounts of EMF: low frequency/long wavelength radiation is usually measured in terms of the strength of the magnetic field (in gauss or milli-gauss); while higher frequency radiation is described in terms of the amount energy absorbed by the body (in Sieverts). The unit of measurement varies with the type of radiation, and unfortunately no single instrument is able to measure across the whole spectrum.
Exposure levels to EMFs around the home are in the range of 0.1-2.5 milligauss, while for homes near or under high-tension powerlines, these levels can vary as much as 5-100 milligauss.
The current standard governing RF generators covers the potential biological and environmental effects of certain frequencies. This standard is the culmination of efforts by several organizations, including Standards Australia, the Australian Radiation Protection And Nuclear Safety Agency (ARPANSA) and the Australian Communications Authority.
In 1997, the ACA introduced the EMC (Electromagnetic Compatibility) Compliance scheme, which was designed to limit the amount of electromagnetic interference according to the Radiocommunications Act of 1992.
In 1998 the ACA changed this to a self-regulated system, with the onus on manufacturers to ensure their products met the standard. Obviously, loopholes emerged and this was scrapped in the same year.
In January 1999, the regulations were rewritten so that the scheme became totally standards based, and the C-Tick became compulsory on applicable electronic items. A C-Tick (see diagram) is essentially a mark identifying that the device meets Australian EMI standards. The standard is based on the International Commission of Non-Ionising Radiation Protection (ICNRP), which aims to regulate according to frequency. It also allows some devices into the country as they emit over the previous limit (which was 200 ?W/cm² -- the amount of microwatts per square centimeter -- which mobiles safely emit under).
The main generators of RF in a common computer are the monitor, the power supply, the processor (which is increasingly prominent as core frequencies increase), and the add-in cards and drives.
The humble CRT monitor has long been the scourge of the PC world -- at least in the litigators' minds. In the 70s and 80s the CRT was linked to miscarriages in women and other effects, and several studies were conducted but little was proven. At the present time, the CRT is still the highest generator of EMF: for example a 17in CRT can produce 7-9 milligauss, while in comparison a 15in LCD produce around 0.1 milligauss.
The main RF outputs of a CRT, however, is not from the screen but from the back and sides. The screen itself acts like an air ioniser, as it attracts dust particles -- potentially benefiting your health!
The total emission level of your average computer is up to 20 milligauss, including the monitor. The average user -- sitting at arm's length would cop a dose of around two milligauss.
RF interference isn't the first thing on most computer modders' minds, it just happens to be incidental to showing off really cool gear. But what is with all the warnings? Are there risks involved with unshielded computers?
Perspex cases can only be used for 'demonstration' purposes, according to the few Australian distributors who stock them, as they are useless at shielding RF signals. Perspex windows are also bad at containing RF.
The Australian Communications Authority (ACA) helps regulate the emissions of electronic products, and says it's perfectly legal to sell unshielded PC cases in Australia: 'A plastic case may be supplied to the market legally. If it contains a power supp
Issue: 133 | February, 2012