Americium-241 Ion Chamber - Radioactive Source- Alpha emitter

Americium-241 Ion Chamber commonly used in Ionization type Smoke Detectors

These radioactive sources contain Americium-241 (Am-241) an isotope of americium. Like all isotopes of americium, it is radioactive, with a half-life of 432.2 years. It is the most common isotope of Americium as well as the most prevalent isotope of Americium in nuclear waste. It is commonly found in ionization type smoke detectors.

Americium-241 is a strong Alpha emitter and is often used to make Neutron Sources.

Inside the aluminum and plastic shell of the Ion chamber is a small button like disk about 6 mm in diameter with exposed Americium-241 on one side in a recess. The Americium-241 is blended with other metals often Gold and plated in the recess.

On the top of the source, it is labeled as 0.8 uCi but the actual activity can vary.  I tested these with a Multi Channel Analyzer and a Ludlum model 43-5 alpha sensor, and was getting activity around 1,500 CPS.  I compared this to a new Polonium-210 source that was 8 mCi which gave me a reading of 15,000 CPS.  So, these could be useful little sources for small experiments.

These also emit some detectable low-level gamma radiation but at these low levels it is exempt from license requirement.  However it is a violation to use these other than intended as a ion chamber or to disassemble the unit.

I will not be responsible for any missus, injuries' or physical damage.  Use these at your own risk.

From the manufacturer:
100% Brand New and High Quality.

1. Model: NAP-07 Ion Chamber used in Smoke Sensor nuclear experiments
2. Outer metal housing Diameter: 37mm
 
Specifications:
1. Ionization source characteristics and radiation safety performance :uCi
2. The ionization chamber fitted with a high performance and low activity of Am-241 ionization
3. Ionization source activity: 0. 8uCi ( 18KBq . 0. 8uCi±10% ( 30KBq±10% )
4. Ionization source a spectroscopy: peak: 4. 5MeV ± 10%, FW HM<0. 7MeV
5. Safety grading standards ( GB4075, IS02919 . C64444
6. Ionization chamber radiation dose rate at 25cm: 0. 03mGy/ ( 1mGy value lower than population dose standard )
8. Conditions: outer electrode and the source electrode voltage ( VDD supply voltage ): 9V
9. Environment temperature: 20 + C: close to atmospheric pressure standard atmospheric pressure, clean air
10. Collecting electrode equilibrium potential: 5. 3~6. 5V
11. Collecting electrode potential with the smoke concentration change
12. Light reduction rate was 1% feet: 0. 6V
13. Light reduction rate was 4% feet: 2. 2V
14. Insulator leakage current ( Max ): 0. 5Pa
16. Capacitor ( collection of extreme outer electrode + to the source base ): 6. 0pF