Scaffolding safety rules 4
To be continued:
FOUNDATIONS
The purpose of good foundation or mud sill is to distribute the shoring load over a suitable ground area. The size of the footing or sill is determined by the total shoring load carried over a particular ground area, and by the nature of the soil supporting these sills. The total shoring load should be computed and
the sills designed accordingly. Suitable sills should be used on a pan or grid dome, floor, or any other floor system involving voids, where a frame leg could concentrate an undesirable load on a thin concrete section. When shoring from earth or fill, the area should be leveled and the sills spaced in a pattern assuring adequate stability for all shoring legs.
ERECTION OF FRAMES
The work of erecting the shoring should be under the supervision of a person with proper experience and aptitude for securing a safe installation. Shoring layouts made by a qualified shoring designer must be strictly adhered to when locating frame legs. Layouts may be obtained from your shoring supplier in most instances. Advance planning will help the erection of frames to progress smoothly. The material should be unloaded as close to the area to be shored as possible and should be arranged in the order it is to be used. Adjustment screws should be set to their approximate final adjustment before setting up the shoring units. At this time, a person should check to see that all frames which require coupling pins have them, and that all frames which require accessories at the top do not have coupling pins. Consult safety rules as recommended by the Institute.
To expedite erection of the shoring and to be sure the loading is distributed the way the shoring is designed, the location of each tower should be marked on the floor by use of chalk line or some other simple method. If required, sills should be placed first. After the location of the shoring towers has been marked, the adjustment screws or base plates, whichever is to be used, along with the necessary braces, should be distributed to each set of marks indicating the location of the tower. After assembling the basic unit it should be leveled so that no matter how high the final tower is to be, the additional frames will be level and plumb as they are installed. When the basic unit is leveled, it is ready to receive the next tier of frames. For higher lifts, a work platform is easily formed for erecting the shoring by using planks on the top horizontal member of the frames. Tie towers of shoring frames together with sufficient bracing to make a rigid, solid unit.
FINAL INSPECTION OF ERECTED SHORING EQUIPMENT
The following is a list of check points to be covered when making a final inspection of shoring equipment prior to the placing of concrete on the form. All points should be carefully checked to insure a safe and accidentfree job.
1. Check to see that there is a sound footing, or sill, under every leg of every frame on the job. Check also for possible washout due to rain.
2. Check to make certain that all base plates or adjustment screws are in firm contact with the footing or sill. All adjustment screws should be snug against the legs of the frame.
3. Obtain a copy of the shoring layout that was prepared for this specific job. Make sure that the spacings between towers and the cross brace spacing of the towers do not exceed the spacings shown on the layout. If any deviation is necessary because of field condition consult with the qualified shoring designer who prepared the layout for his approval of the actual field setup.
4. Frames should be checked for plumbness in both directions. The maximum allowable tolerance for a frame which is out of plumb is (1/8 inch in 3 feet). If the frames exceed this tolerance the base should be adjusted until the frames are within the tolerance.
5. If there is a gap between the lower end of one frame and the upper end of another frame, it indicates that one adjustment screw must be adjusted to bring the frames in contact. If this does not help, it indicates the frame is out of square and should be removed.
6. When two or more tiers of frames are used, each shall be braced to at least one adjacent frame.
7. While checking the cross braces also check the l