If it’s not enough to trump non-existent dangers of cell phones and wifi, one thing that really makes my skin crawl is seeing a cell phone or other RF device portrayed with the symbol for ionizing radiation. Not only are these devices not radiation hazards of any kind, but the radiation which is associated with cell phones, Wifi and other such devices has absolutely nothing to do with ionizing radiation. The effects on the body are entirely different, the methods of protection are entirely different and the method of generation is completely different. Actually, there’s more similarity between ionizing radiation and visible light than RF radiation.
Yet, I see it over and over and it’s so wrong, it’s about time someone explained it to these numbskulls such as here, here and here. Even mainstream sites like Engadget seem to have no idea of the difference between an X-ray machine and a cell phone.
The Trefoil is NEVER EVER correct for denoting RF radiation! Actually, in some jurisdictions it is illegal to misslabel radiation hazards, although the context its used in does not generally come across as a real hazard warning. However, there are recognized standards for how RF and ionizing radiation hazards are to be labeled, and although cell phones don’t present a radiation hazard, if they did, the label would still be wrong!
Here’s some background…
Denotes nuclear radiation, ionizing radiation and radioactive materials
The “trefoil” is currently the standard for denoting radiation hazards from ionizing radiation. This includes nuclear radiation, x-rays and particle beams. In general, nuclear radiation is ionizing and consists of alpha, beta and gamma radiation. There is one exception to this and that is neutrons, which are not charged particles and are therefore do not ionize material on their own, although they can by secondary reactions. The trefoil may also be used to denote neutron radiation, which often is accompanied by ionizing radiation anyway.
The symbol is standardized and recognized by all major regulatory agencies and standard bearers. There are even standards for how it is to be drawn and used. It may appear with text describing the nature of the hazard, whether x-rays, radioactive materials, neutron generators and so on. It also is commonly used on radioactive materials which may not have any external hazard or which are sealed. In this case the symbol would appear on a shipping slip or placard to describe the nature of the material being transported. In the US, DOT regulations divide radioactive materials into three categories for labeling, depending on the dose rate at the surface.
It was first developed in 1946 at the University of California Radiation Laboratory in Berkeley, although it is similar to other symbols which had been in existence before this. The first rendition was magenta on a blue background, although this is no longer considered the standard. It is suggested that the symbol represents radiation originating at a center point, such as a nucleus. It has also been suggested that the symbol may be intended to look like a reel of film, such as would be used in a ‘film badge’ to measure individual radiation exposure. Early variations of the symbol included the use of arrows or lightning bolts on the three fins. More information on the origin here.
Variations on the Trefoil:
Some variations on the symbol exist. These include additional warnings. Another variation is the use of the letter ‘N’ in the symbol to denote neutron radiation. This, however, appears to be non-standard and is not recognized by any regulatory bodies. It has appeared none the less and may be used in such circumstances as a radiation alarm which would use the symbol to clarify what kind of radiation is being detected.
In general, the standard trefoil is considered proper for neutron sources, gamma, x-ray or other radiation fields. It may or may not be used for particle beams, depending on the circumstances.
The fallout shelter symbol was first standardized by the Department of Civil Defense in the United States, however it is also recognized elsewhere including Brittan and Canada. The initial intention was to use the standard trefoil design to mark fallout shelters, but this was rejected for two reasons: First, fallout shelters are intended to be safe places to take shelter from radiation or other hazards from a nuclear attack and secondly because it may cause confusion between fallout shelters and areas where radiation hazards existed or where materials were being stored.
Thus the symbol was modified into a three triangle design which does not have a central circle and where the edges of the triangles lack the curve of the radiation symbol. However, it still bares a resemblance to the original symbol.
These signs and variations on them were once common in public buildings, schools and other major structures built during the cold war. Today they are still seen from time to time on public buildings and schools.
New Symbol for Public Warnings:
In 2007, the IAEA and ISO announced the adoption of a new radiation symbol, intended to be used in special circumstances where the public may be in danger due to a radiation hazard. The sign includes the trefoil and will not replace the trefoil by itself for general purpose use. It is believed that the new design will be able to better express symbolically that there is danger and to keep away. It is intended to address the problem of populations which may not be literate or may be language isolated and unaware of the dangers expressed by the trefoil or other warning signs.
It clearly says “If you see a fan with wavy lines or sperm coming out of it, you should dance while moving to the side, away from the pirates.”
Other warning symbols for other types of radiation:
Optical radiation, including extremely intense lights and UV radiation:
For UV Radiation, a similar symbol, sometimes in violet may be used as part of a warning sign:
Laser light uses the following symbol and sign, with the class of laser included:
High Intensity Magnetic or Electromagnetic Field:
RF Radiation Uses the Following. This is what Would be used for a cell phone, IF it were over one hundred times more powerful than they generally are:
As used in:
Some non-standard or unusual warning signs I’ve encountered before:
You may have seen the biohazard symbol, shown to the right, used in the context of radiation, as in a radiation story or on a radiation suit shown in a movie or other fictional context. This is entirely wrong. The biohazard symbol has nothing to do with radiation or radioactivity of any kind, ionizing or otherwise! It is used to denote materials or areas with the potential of infectious hazards, such as bacteria or viral cultures, human tissue samples, body fluids, dead bodies or other human material which may transmit infectious disease. It may also be used to mark non-human material which is believed to pose an infectious hazard, such as biological weapons materials, contaminated foods and similar.
It may also appear on equipment or material intended to deal with biohazard situations, such as body fluid clean up kits, gloves and so on.
This entry was posted on Saturday, May 3rd, 2008 at 6:16 pm and is filed under Bad Science, Good Science, inverse square, Not Even Wrong, Nuclear, Obfuscation. You can follow any responses to this entry through the RSS 2.0 feed. You can leave a response, or trackback from your own site.
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