The crew spent the morning staging around the BSC-7 dome by craning a garbing-staging cleanroom, a couple of staging tables, the external purge air unit and the HEPA filter into position. A variety of other paraphernalia was transported as well. After lunch, Mark L. and Zack "bunnied-up" to start work on the dome. They removed a large conflat (preserved in Class A condition) to allow better air flow inside the dome. Mark took and Zack recorded five FTIR samples. Then, Mark proceeded to vacuum the welds. He got about 3/4 of the upper half completed.