（1）Adjusting the height of transverse rails of front legs and middle legs  when erecting girder or moving from one pier to keep main girder’s longitudinal slope≤0.5%，transverse slope≤0.5%.   

  （2）there should be a commander who directs the order at the present site, and the front legs must be firm, and someone who checks it specially.     bridge girder launcher
（3）perfect checking mechanism should be established. Before construction, construction and after construction of per span of the bridge girder launcher should be checked, finding the questions and deal with them timely to make sure the construction can be done safely.
（4）The normal working wind speed should less than 6 grade when bridge girder launcher works in the open air ; when the wind exceed 6 grade, the bridge girder launcher shouldn’t moving from one pier to next pier, and components should be locked; the machine can’t work in thunderstorm day and must cut off power.  
 （5）It’s prohibited to put the goods randomly on the bridge girder launcher  to increase its load.
（6）check the steel rope is broken or not,  the circuitry leaks electricity or not, the brake is reliable or not, and after the reducers get enough lubricating oil and the oil lubricate the open gears, the machine start to work; the safe circle of steel rope on the drum shouldn’t less than 3;checking the surface and fixed parts after every shift of steel rope and making a specific check every 7～11 days;
（7）the brake system of winch is allowed to start again after it checked;

（8）the longitudinal traveling is prohibited when the launching crane is erecting the girder, and traveling rail should be paved flatly and smoothly. Someone who should be maintain the rails specially.
（9）the speed of lifting and translational velocity should be slowly to avoid leaning and side tumbling;       
（10）After the legs move to their places, plug the safe pin to prevent the hydraulic cylinder from bearing force for a long time;
  （11）When the tubes of components are fault, the operator should cut off power immediately, and it is checked and repaired by the professional technician; the operator shouldn’t disassemble privately; when checking and repairing the machine , the technician must cut off the power. 
（12）the operator should be qualified and get the operational training. The non- operator is prohibited to operate the machine strictly.       
（13）the goods are prohibited to throw out from bridge girder launcher strictly; it is prohibited to lift goods to pass over head strictly；it is prohibited to lift workers by hook or goods strictly；the inflammable goods are prohibited to put on the launching crane strictly;
      
（14）the lifting ,longitudinal traveling and transverse traveling shouldn’t work together;  
（15）the bridge girder launcher mustn’t be operated if the conductive part, the shell of naked electric wire or protective cover isn’t complete.