Test Chamber Improves Accuracy of Inhaler Testing

Thermotron has developed a state-of-the-art Impactor Test Chamber to improve accuracy and repeatability of inhaler and nebulizer product testing. By designing a sophisticated, dualcompartment environmental enclosure, Thermotron is able to precisely control temperature and humidity conditions. New developments in US and European Pharmacopeia testing criteria assisted in shaping this configuration.

The test chamber includes two separate, independently controlled test spaces: one compartment for conditioning the temperature and humidity surrounding the nebuliser or inhaler, and one for cooling the impactor. Inside the nebuliser/inhaler compartment, temperatures range between 0ºC and 40ºC and humidity ranges between 30% to 90% RH. Temperatures within the impactor test space can be controlled down to 0ºC. An adjustable shelf in the impactor compartment allows interface with two different types of impactors: the Next Generation Impactor (NGI) and the Andersen Cascade Impactor (ACI). This versatility of testing various environmental conditions sets Thermotron’s Impactor Test Chamber apart from other test solutions.

Proposed revisions to US and European test standards highlight the negative effect evaporative loss can have on accuracy. Impactor related heat loss can cause evaporation, which reduces droplet size and results in artificially low particle size measurement. The Thermotron Imactor Test Chamber cools the impactor in a controlled environment and/or encloses the inhaler device in a temperature and humidity conditioned

environment, reducing the potential for evaporation of aqueous droplets after aerosolization and improves accuracy. The chamber can host multiple impactors for pre-conditioning, potentially reducing time required for receiving FDA approval.