Direct-read colorimetric exposimeter

摘要

A direct-read exposimeter for providing a visual, graded measurement of color variation corresponding to different ranges of dosage exposure to a polluting gas in the atmosphere over a given time period. The exposimeter includes a color-forming member and at least one gas-diffusion control member within an enclosure formed between a base and a cover. The cover has a number of openings exposed to the atmosphere in alignment with a number of separate diffusion zones formed in the gas-diffusion control member.