PicoRad LS Vials
The PicoRad vial is a 6 cm. high by 2.5cm. diameter high-density polyethylene liquid scintillation vial, able to fit a standard LS rack. The 22-ml capacity vial is designed to hold a small canister near the opening above the scintillating fluid. The canister, made of high-density polyethylene, contains a patented pharmaceutical-grade charcoal-silica adsorption material. This patented device configuration allows for minimum attenuation of the scintillation signal by the charcoal. Perforated end caps allow air to circulate through the mixture and retain any charcoal dust. A polyethylene cap, capable of sealing tightly, prevents the loss of radon gas from the vial. The canister is manufactured by an ISO certified company to exacting specifications. PicoRad vials are assembled and bar-coded to maintain tracability of the individual vial to the manufactures lot designations. Each batch of material is extensively tested for freedom from residual radiation and adsorption performance.
The PicoRad vial has shown excellent reliability over the years and is capable of reaching its maximum adsorbence of radon in as little as 8 hours. The charcoal-silica adsorbtion material shows good resistance to typical environmental humidity conditions for up to 72 hours. Remember that the EPA protocols for testing residential dwellings and public buildings require a 48-hour exposure time to capture two diurnal cycles of radon.
The PicoRad vial is now shipped in shrink-wrapped trays to aid in the protection of the vial from moisture. It is recommended that opened trays be stored in a 4 mil plastic bag with a desiccant to insure the best shelf life. It can be expected that a PicoRad vial protected from moisture should have a shelf life of no less than two years.