Practical leak detection and leak rate measurement applied to a hot cell for radiopharmaceuticals preparations in a GMP compliant Laboratory

Rodrigo da Silveira Santos; Carlos Leonel Zapparoli; Joel Mendes dos Santos; Gabriela Franco da Rosa Caetano; Marcelo de Gusmão Paraíso Cavalcanti; Delvonei Alves de Andrade

doi:10.15392/2319-0612.2026.3004

Authors

Rodrigo da Silveira Santos da Silveira , Nuclear Energy Research Institute
Carlos Leonel Zapparoli Nuclear Energy Research Institute
Joel Mendes dos Santos Nuclear Energy Research Institute
Gabriela Franco da Rosa Caetano University of São Paulo
Marcelo de Gusmão Paraíso Cavalcanti University of São Paulo
Delvonei Alves de Andrade Nuclear Energy Research Institute

DOI:

https://doi.org/10.15392/2319-0612.2026.3004

Keywords:

hot cell, leak tightness, pressure change method, radiopharmaceutical

Abstract

Hot cells are containment systems used in radiopharmaceutical production, designed to ensure radiation protection and product quality. Leak tightness testing is a mandatory requirement under CNEN NN 6.13 standard, as it directly impacts worker safety, environmental protection, and product integrity. This study aimed to perform a practical pressure change leak test in a hot cell used for radiopharmaceutical preparations, in accordance with applicable technical standards. The pressure change method was applied using pressures between 1.6 and 2.5 higher the working pressure for a testing time of 15 minutes. The method proved practical, requiring no highly specialized equipment, although its sensitivity to temperature highlights the importance of high-precision thermometer. Results showed that while the method is suitable for ISO 10648-2:1994 Class 2 compliance, it may not be adequate for Class 1 due to the risk of mathematically inaccurate results under temperature variations. Multiple rounds of leak detection and repair were required to achieve the required containment level. Overall, the DC, RIC, CIC, and Solid Waste chambers met Class 2 leak tightness requirements, being suitable for use in radiopharmacy facilities.

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