Paul Daniel Apr 29, 2019 Hi Hagai - If you stability chambers are less than 2 cubic meters in volume, you can use 9 probes. One probe in each corner, and one in the center. Personally, I like to use more sensors for sensitive equipment like stability chambers, so I would add 6 more, and locate each one in the center of each side of the unit. Stability chambers get remapped frequently - I see requalification intervals of 6 months to 3 years. I know this was a short and quick answer. For more detail see our existing articles and webinars listed below: https://www.vaisala.com/en/blog/2018-09/mapping-sensor-placement-stability-chamber-manufacturing https://www.vaisala.com/en/blog/2019-03/coldhot-spots-how-many-probes-are-really-needed-stability-chamber-monitoring https://www.vaisala.com/en/blog/2018-09/streamlining-stability-testing-sample-intervals-10-seconds-vs-10-minutes https://www.vaisala.com/en/blog/2018-09/humidity-sensing-stability-chambers-two-important-guidances-redundant-humidity-sensors-and-intervals-requalification https://www.vaisala.com/en/blog/2018-09/loaded-question-50-60-load-stability-chambers-too-or-just-incubators https://www.vaisala.com/en/events/webinars/lp/stability-studies-monitoring Thanks! Reply