Vermont, USA
What Is Americium-241?
Americium-241 is a malleable, silvery white metal that does not occur naturally. It was first produced in 1944 in a nuclear reactor at the University of Chicago. Nowadays it is mainly produced as a byproduct within nuclear reactors and it is extracted from spent nuclear fuel rods.
It’s radioactive half-life is 430 years but in total it takes millions of years for it to finish its radioactive decay process.
Why do ionization smoke alarms use radioactive material?
Ionization smoke alarms use ionizing radiation to generate a small electric current between two metal plates. When that current is disrupted by certain types of particles, the alarm sounds.
Ionization technology is very susceptible to nuisance alarms from burning toast or paper, cooking vapours or steam from a bathroom shower.
Dr Michael Fonda
PHHA, NT, Australia
Doctors Push For Radioactive-Free Smoke Alarms
Dr Michael Fonda, 7 News NT, Australia, 23 March, 2011
On March 23, 2011, Dr Michael Fonda from the Northern Territory branch of the Public Health Association of Australia (PHHA) said the Northern Territory Government should consider legislating for the use of non-radioactive (i.e. photoelectric) smoke alarms:
Public Health Association of Australia - Radiation Concerns
Typical Ionization Alarm with
Warning/Disposal Sticker
Radioactive Ionization Alarms - Overview
Consumers and authorities are finally beginning to discover that ionization alarms have inherent, life-threatening defects and are a source of long lived radioactive waste.
(Note: all ionization alarms contain radioactive material).
The global movement to eliminate ionization alarms and replace them with safe, affordable alternaties is the subject of the film, Smoke Alarm Recall.
How Is Americium-241 Used?
The most common use of Americium-241 is in ionization smoke alarms, which rely on the alpha particle decay of Americium-241 to ionize the air in a gap between two electrodes, causing a tiny electrical current to flow between them. When a certain size of smoke (i.e. sub-micron from burning toast for example) enters the space between the electrodes, the alpha radiation is absorbed by the smoke particle, the current is interrupted, and the alarm is activated.
The disposal of radioactive waste: a burning issue that won’t go away.
Many smoke alarms need replacing after ten years. This results in many thousands of ionization alarms being dumped individually into ordinary landfill each year. Each ionizing alarm remains radioactive for many thousands of years and accumulates in the environment.
Whilst many authorities consider it OK to dispose a maximum of two ionizing alarms at a time, the current position of many councils' refuse legislation is that more than ten alarms are classified as radioactive waste and must be disposed of in specially designed repositories which also remain radioactive for thousands of years.
It is clear that continued disposal of ionizing alarms whether in landfill or in specialized radioactive waste repositories is problematic. In contrast, there are no environmental issues with disposal of photoelectric smoke alarms.
What health risks does Americium-241 pose?
The radiation released by Americium-241 smoke alarms is said to only marginally increase the level of background radiation already in our homes. Nonetheless, it is an established scientific principle that all radiation is harmful, so even a small increase is to be avoided if a better alternative exists.
Americium can escape from ionization smoke alarms after a fire or if the unit is taken apart, say by an inquisitive child, which actually happened in 1995 in a small American town near Detroit. If inhaled or swallowed Americium can get deposited in the lungs, and other organs of the body where it can remain radioactive for many years and increase the risk of developing cancer.
More info: www.epa.gov/rpdweb00/radionuclides/americium.html
What can we do about this radiation health and environmental risk?
1. Discover the truth about the ionization smoke alarms in your home by sending a
Smoke Alarm Disclosure Letter.
2. Once you discover the facts, replace all ionization alarms with photoelectric alarms.
3. Consider returning your ionization alarms to your local state health department.
4. Tell your local councillor or state politician that the waste burden imposed by ionization smoke
alarms is unacceptable and needs to be dealt with urgently.
5. Tell all your family and friends.
1: Radioactive Ionization Alarms - Overview
PHAA Position on Smoke
Alarms in Residential Accomodation
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