Abstract: Radiation shielding for limiting the transfer of heat by radiation is provided for a ceiling closure having a curtain wall shiftable from an open position allowing air flow through an opening in the ceiling to a closed position in which the curtain wall blocks air flow through the opening. The radiation shielding comprises a plurality of radiation shields formed of air impermeable, heat resistant, flexible fabric sheets folded for storage and for unfolding into generally planar sheets with shifting of the curtain wall into the closed position wherein the fabric sheets define and confine a dead air space. The sheets are preferably made of tightly woven asbestos coated to retain asbestos fibers against liberation into an air stream. Reflective coatings act to retard the radiation of heat.