Microclimate Humidity Control

Museum Climate Control Solutions

Control humidity, temperature, pollution, and oxygen levels in display cases, storage cabinets, picture frames or any sealed enclosure using our state-of-the art techniques.

Should I use passive or active control?

What could be simpler than placing a few cassettes in a drawer and reconditioning them as needed? Then again, it’s so easy to set your desired RH level on a display and occasionally add a little water to a reservoir? Better, a state-of-the-art solid state humidity controller never needs water! Which solution is best for my application? ┬áThere’s no easy answer, but Keepsafe can help you find the appropriate solution.

Passive humidity solutions work best where the showcase volume is small, the enclosure can be extremely well sealed, and where stable mid-range humidities or very low humidities are needed.

Active microclimate control devices can be used to protect large or small showcases. Active units generally have far greater treatment capacity than passive solutions, and are often used on larger showcases, multiple showcases, or where passive control is not an option. Humidities from below 20% to above 60% can be easily attained with the appropriate devices and enclosures. Large remote microclimate generators are used to provide climate control for large groups of showcases or storage cabinets, often for entire galleries. Miniature units may be installed in or near display cases.

Both active and passive solutions demand some attention to ensure that they are operating properly, and a combination of both approaches often offers increased benefits.

A general rule may to consider active humidity control solutions if your installation is large, but if the showcases are small and few, then passive may be your best bet. It is important to note that the best (and most expensive) showcases do well with either system, while simpler, inadequately sealed, or very large showcases may require the power of active control. (Please visit our page on Museum Showcases). Keepsafe Microclimate Systems can help you explore your options, from a casual consultation to the provision of a complete formal study and recommendations. Contact us.

Note that some of our humidity control products can often be used in concert with oxygen and pollution control. Please see our Case Studies and other links for more information on our products. All our active microclimate control products have been developed with, and are manufactured and serviced by Preservatech Inc.

What do the experts say?

“At a point, if the leakage rate is very high (above 2 air exchanges per day), so much silica gel would be required that passive RH buffering is no longer a viable alternative. For cases with a high leakage rate, it is essential to reduce the rate of leakage, or consider an alternative approach such as the use of an active RH control system.”

– Steven Weintraub


“Providing a microclimate in a well-sealed case is a low-cost alternative to controlling the entire exhibit space.”

– Toby Raphael and Nancy Davis

Exhibition Conservation Guidelines

National Parks Service

Harpers Ferry, VA

“While heating, ventilating, and air conditioning (HVAC) standards and the tolerances of buildings housing collections may continue to dictate environmental standards as a whole, the display case becomes the area within which the greatest good or harm to objects is realized.”

– Pamela Hatchfield

Museum of Fine Arts of Boston Pollutants in the Museum Environment

Microclimate solutions can provide substantial energy savings. Visit our page on Green Solutions to learn more.