1. Your Electromagnetic Safety Blanket
or Not!
Wes Lemstra
Engr 302
Spring 2002

2. However… Let me try again. What is EMF?
Kudos to Troy for already explaining so well.
However…
Let me try again.

3. Duh!! We just did a whole course on that…
What is EMF?
Duh!! We just did a whole course on that…
Electro Magnetic Fields
They include
electric fields generated by charged particles
magnetic fields generated by charged particles in motion
radiated fields such as TV, radio, and microwaves.

4. Are EMFs Harmful to Humans?
A little biology
iron is nessasary in that that it plays a large role in energy metabolism and in the production of red blood cells (erythropoesis)
Iron is a transition metal and takes part in redox processes
EX. reduction by an organic substrate and reoxidation by oxygen

5. Are EMFs Harmful to Humans?
More biology
two thirds of the body's iron is in the pigment haemoglobin
Pigment haemoglobin transports oxygen in red blood cells
On average, an adult male has 1000 mg of iron in storage.

6. Are EMFs Harmful to Humans?
Iron in our blood is highly effected by EMF
The permeability of the cell membrane of our nerves, blood vessels, skin, and other organs is effected.
The DNA of the chromosomes has been shown to be effected by EMFs as well.

7. How much is too much?
Sweden has imposed a safety limit for exposure to ELF (Extremely Low Frequency, 6.67 Hz and lower) magnetic fields at 2.5 mG, and VLF magnetic fields at only 0.25 mG
U.S. has no set limit, but most people use Sweden’s limits
An average hairdryer, vacuum cleaner, or can opener emits approximately 300 mG .

8. Too much EMF?
Important to note is the amount of time in proximity to the electric field is a very important factor.
12 hours near a 80 mG poweline is more dangerous than a 3 minute exposure to a 1000 mG microwave

9. Are EMF’s a problem? Three recent studies indicate that it is.
epidemiological studies in Sweden by Maria Feychting showed that individuals exposed to high magnetic fields at home and at work had 3.7 times the risk of developing leukemia compared to those not exposed.
recent research reports have identified elevated risks of breast cancer among women working in jobs with presumed higher than average exposure to EMFs.

10. What about Electric Blankets?
Electric blankets create a magnetic field that penetrates about 6-7 inches into the body.
an epidemiological study has linked electric blankets with miscarriages and childhood leukemia
The magnetic field for those who sleep under an 120 vac electric blanket are up to 100 mG

11. What about Electric Blankets?
The reason there is no law against use of electric blankets is that there is no real proof one way or another
I would submit that we should ere on the side of caution rather than on the side of economics

12. Questions?