The Ogawa Passive Sampler is a simple passive sampler,
requiring no outside source of power which can determine the quantity of basic air-quality gases in ambient air,
including O3, NO, NOx, NO2, SO2, and NH3.

It is extremely accurate, easy to use,
and less expensive than most.

It has been used worldwide for over 25 years,
and is highly regarded as one of the
best passive samplers in the industry.