The following bridge erecting machine construction risk control measures are wrong ().

202 1 new textbook P257

1. When using bridge erecting machine to erect beams, a reasonable erection scheme and corresponding safety technical measures shall be formulated. Make safety technical disclosure to all operators (including mechanical operators). 4. When erecting a beam, its power supply must be controlled by designated personnel, and a qualified full-time electrician should be set up; The mechanic should follow the shift to prevent all kinds of accidents caused by sudden power interruption or electrical and mechanical failure of the bridge erecting machine. 7. All preparations should be made for the longitudinal movement of the bridge erecting machine, and it is required to be in place twice, and it is not allowed to stop halfway. 9. When the installed bridge has a vertical slope, the longitudinal displacement and sliding of the bridge erecting machine should be prevented. 15. The bridge erecting machine shall be equipped with lightning protection devices.