Reconfigurable manufacturing systems have been proposed in the last decade to deal with mass-customization problems and volatile market environment. If physical design, control or scheduling issues of these systems have been studied intensively, very few works concern the inherent safety problems. However this issue is of first interest for reconfigurable robotized cells with frequent interventions of human operators. The present paper must be considered as a position paper introducing the new concept of “cooperative” safety bubble. This last aims to insure operator’s safety by cooperation between “safe” robotized units and safety devices. A preliminary implementation methodology of such safety bubble is presented and some corresponding research issues are proposed.