Kodalpha Radon dosimeter

The Kodalpha Radon dosimeter is a very user-friendly and inexpensive device for the one-time radon measurement. It is a Radon detector of the "passive-type" which doesn't require any power source. It is sufficient to place one single Kodalpha Radon dosimeter in each room which needs to be tested for Radon. The Kodalpha Radon dosimeter is analysed by a dedicated and validated laboratory. The result of the measurement indicates the average Radon concentration for the time of exposure.

Application

The Kodalpha Radon dosimeter (see picture) is a small, black box with a hinged cover containing the Radon sensitive part (type LR115).

The dosimeters are preferably placed in those rooms, where you and your children usually spend most of the time (children's room, sleeping room, living room...). Since the highest Radon levels in a home can be expected in the basement, we also recommend to place a Radon dosimeter in this area.

The Radon measurement is started by simply opening the cover of the dosimeter. For more details, please see our Kodalpha manual (pdf, 145kb). The duration of a Radon measurement (also called the "exposure time") with the Kodalpha Radon dosimeter can last from two weeks up to one year. But since longer exposure times in general give more significant results, we recommend to keep the dosimeters exposed for three months.

A special feature of the Kodalpha Radon dosimeter allows, that the detached cover of the device holding the LR115 badge can be used for the measurement all by itself. Discreet Radon measurements can be made in this way by simply attaching this part of the dosimeter on a piece of furniture or under a table with a double-sided adhesive tape. The method of discreet measurements is very advantageous for Radon surveys in schools, kindergardens or workplaces.

When the Radon measurement is terminated, the cover of the dosimeter is separated from its base and inserted in the provided plastic pouch. This keeps the LR115 film badges safe and Radon proof for the return shipment (see picture on the right). The exposed dosimeters are then sent back to GT-Analytic in the pre-addressed envelope by ordinary mail. NOTE: In contrast to most other Radon testing devices the Kodalpha Radon dosimeter doesn't require special packaging or express mail service for shipment. This feature additionally accounts for the cost-effectiveness of our dosimeters!

Analysis of the dosimeters and results

The Kodalpha Radon dosimeters are processed and analysed by a specially dedicated and highly experienced laboratory which for more than 10 years is regularly validated every 6 months. Each film badge carries a serial number and after analysis will be kept in the laboratory's archives together with the analysis results and the applied parameters.

The individual analysis reports are forwarded to our customers by mail or email within two weeks upon receipt of the exposed Dosimeters.

The analysis report contains the following information:

• The average Radon concentration [Bq/m³] for the time of exposure.
• The Standard deviation (2•σ) as [Bq/m³]
• The serial number of each Dosimeter
• Starting date, ending date and duration of the Radon measurement.
• Optional: The location of the detector if indicated by the customer

Measuring principle of the Kodalpha Radon dosimeter

When Radon and some of its radioactive products undergo the process of radioactive decay extremely small atomic particles are emitted at high speeds. This phenomenon is called Alpha Radiation. When such particles hit the Kodalpha film badge they damage the structure of the Radon sensitive layer. In the laboratory, the films are chemically treated. After this process small holes become visible on the film, - one for each former impact of an Alpha particle. The number of these holes per cm² is determined and since the exposure time of the dosimeter is known, the average Radon concentration can be derived precisely in this way.

Features of the Kodalpha Radon dosimeter

• The Kodalpha Radon dosimeters are not negatively affected by electrostatic charge, humidity, dust or finger prints. NOTE: Only care must be taken to avoid deep scratches on the film badges as well as long term exposure to direct sunlight.
• Unlike most other dosimeters the Radon measurement starts immediately after the cover of the Kodalpha Radon Dosimeter is opened and ends with no delay as soon as it is closed. This ON/OFF feature not only accounts for the high precision of the Kodalpha Radon dosimeter but also allows to determine Radon levels during certain times. For example if Radon levels want to be detected only during school time, when children and teachers are present.

Additional information concerning projects and bulk purchasers

Unlike other types of dosimeters the Kodalpha Radon dosimeters can be stored at room temperature for more than two years before use. This allows the purchase of a certain stock of Dosimeters and the customer additionally has the advantage of our profiting bulk prices.

No special precautions have to be taken for the proper storing of the dosimeters. It is sufficient to keep them at room temperature but protected from direct sunlight and high Radon levels.

Even exposed Kodalpha Radon dosimeters which are returned to the distributor can be stored in the specially provided plastic pouches for several months before being returned for analysis. Especially in large Radon surveys this feature allows to wait for the return of larger numbers of Dosimeters, which can then be forwarded for analysis in one time. NOTE: The Kodalpha Radon dosimeters don't need special packaging or express mail services for shipment!

Also in contrast to several other models of Radon detectors it is sufficient to place only one single Kodalpha Radon dosimeter in each room which needs to be tested for Radon. This fact helps to save a lot of time and money especially if large Radon surveys are made.

The laboratory where our Kodalpha Radon dosimeters are analysed is best equipped for the processing of large quantities of Dosimeters in short time. More than 1300 individual dosimeters can be analysed per week without difficulties.

For more detailed technical information, concerning physical parameters, applications, sensitivity, principle of measurement etc., please see the document Kodalpha technical details (pdf, 187kb)