Incubators including an enclosure with an internal chamber configured to support a cell culture plate comprising a plurality of wells are disclosed. The enclosure includes a plurality of openings configured to allow access to the wells. The incubators include a sealing element configured to seal the plurality of openings in the enclosure. The sealing element comprises a plurality of openings corresponding to at least a subset of the plurality of openings in the enclosure. Access to the internal chamber can be provided by aligning the plurality of openings in the sealing element with the plurality of openings in the enclosure. Methods for using the incubators are also provided.