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19. Regulations Concerning the Prevention of Industrial Accidents Resulting from Flying Objects and Ground Collapses

There are many occurrences of industrial accidents as a result of the collapse of natural ground and objects falling from high places. To prevent such dangers, employers are required to take the following measures.

1.Measures for prevention of dangers due to collapse of natural ground, etc.

(1) Preventing the collapse of natural ground or the fall of earth and rocks

Carrying out advance research concerning the nature of the soil, strata, etc., whether cracks, water contents, underground springs and/or soil freezes are present, whether buried objects, etc., are present, whether high temperature gas or steam is present, and other relevant factors.

(2) Making the slope of the natural ground, etc., safe

[Sloping in the Case of Excavation by Hand (i.e., not using power shovels, etc.)]

Type of Natural Ground Surface Height of Excavation (m) Surface Slope of Excavation (degrees)
Natural ground consisting of rock or hard clay Less than 5 90
5 or more 75
Other natural ground Less than 2 90
2 or more and less than 5 75
5 or more 60
Natural ground consisting of sand Less than a slope of 30 degrees or less than 5 m in height at the excavation surface
Natural ground after blasting, etc. Less than a slope of 45 degrees or less than 2 m in height at the excavation surface
* Assigning an inspector to check for loose stones, cracks, cave-ins and surface subsidence in such places as natural ground, tunnels, quarries, etc., before starting work.
* Installing shoring, tunnel shoring, etc., and safety net. Establishing an off-limits area.
* With respect to quarries, etc., taking such measures as utilizing posts, leaving posts in place, using lock bolts, etc., and establishing an off-limits area.
* Requiring workers to wear safety helmets.

2.Prevention of dangers due to flying and falling objects

* When throwing objects from an elevated site with a height of 3 m or more, providing throwing facilities and stationing a watchman to oversee such activities.
* For places where there is a possible danger that objects may fall (such as hanging scaffolding, etc.), installing protective netting and establishing an off-limits area.
* When lifting and/or lowering materials, equipment, tools, etc., using a sling rope, lifting bag, etc.
* When operations are being carried out in the upper areas of places such as dry docks, construction sites, etc., requiring workers down below to wear safety helmets.
* When work is being carried out inside the holds of ship, prohibiting activities on different layers at the same time without taking such measures as installing safety net, protective covers or tarpaulins, etc.
* For vehicle-type construction machines that are used places where there is a possible danger of injury due to falling rocks, etc., installing a sturdy head guard.
* With respect to handling cargo piles, securing the load with rope, netting and/or rearranging the stack, and establishing an off-limits area.

3.Prevention of dangers due to falling objects while lifting cargo, etc.

* Installing study head guards on forklifts, shovel-loaders, etc., where there is a possible danger that cargo loads may fall.
* In the case of loading and unloading operations involving trucks, off-road cargo hauling vehicles, in-yard hauling vehicles, etc., and cargoes weighing 100kg or more, assigning an operation leader to confirm that there is no danger of falling cargo at the time ropes are loosened or covering sheets are removed.
* When there is a possible danger of cargo falling from a conveyor, installing a suitable cover or enclosure.
* When using vehicle-type construction machines for other than the designed purpose by lifting cargoes, establishing an off-limits area.
* Setting up an off-limits area in places where there is a possible danger that pulley blocks, pulley equipment, etc., may swing during the operation of piling drivers and pile extractors.
* When lifting and lowering cargo using jack-type lifting machines, establishing an off-limits area and at the same time requiring workers to wear safety helmets.
* Prohibiting passage under cargo hoisting equipment, cranes, etc.

4.Measures for the prevention of dangers due to flying objects during the manufacturing of products, etc.

* When there is a possible danger of flying objects due to cutting, breaking off, etc., during manufacturing operations involving machines, installing appropriate machine covers or fencing. In cases where this is difficult, requiring the workers involved to wear safety helmets.
* Taking the same measures as above in cases where there is a possible danger of injury from flying cutting chips, etc.
* When carrying out the demolition or destruction of structures or the crushing of concrete, stone, etc., by means of a breaking machine, establishing an off-limits area.
* When filling a tire with air by means of an air compressor, establishing a safety fence, etc., to prevent injuries to flying pieces in the event the tire may burst, etc.

("Regulations on the Prevention of Accidents Resulting from Cargo Handling/Cargo Hauling Machines" will be discussed in the next session).