A safety device for use in a fall arrest system, has a safety line drum mounted for rotation and a speed responsive engagement mechanism responsive to the speed of rotation of the drum, which is activated above a predetermined rotational speed of the drum to deploy an energy absorber. Accordingly, the fastening member has both an advantage of a synthetic resin of being inexpensive and light and an advantage of a metal of having strength and gloss having a high-grade sense, and an outer appearance or a texture thereof can be viewed like the metallic member. The dough article also comprises a dough having a cellular network that is substantially free of an active leavening agent. The transfer chamber is connected to the processing chamber and houses the substrate handling robot. The conductive layer covers the active area continuously but covers the dummy area discontinuously; and thus, the active area can perform normal electrical conduction functions while an insulating effect can be achieved in the dummy area. Quantum dots are generated by shining a dot production laser onto a solid object in a quantum dot productionmanipulation apparatus containing superfluid helium therein.