Crane and Hoist Safety

1. Crane and Hoist Safety PUBH 3310 November 13, 2009

2. Objectives • Know hazards associated with cranes • Become familiar with common types of industrial and construction cranes • Understand rigging basics, including the importance of “sling angle” • Be familiar with methods of controlling crane hazards and preventing accidents

3. Outline • Crane Hazards • Crane types • Industrial cranes • Construction cranes • Rigging (and “sling angle”) • Controlling hazards • Inspections and training • Power lines • Equipment failure and crane stability • Other

4. Crane Hazards • Over 250,000 cranes in operation • 125,000 in construction • 80,000 general and maritime • 80 fatalities per year • One death per thousand crane operators in their working lifetime (45 years) • Risk to citizens and other workers

5. Causes of Crane Fatalities A. Suruda,et al, Crane-Related Deaths in the U.S. Construction Industry, 1984-94

6. Crane Types • "Industrial cranes“ • Overhead • Gantry • Jib • "Construction cranes“ • Mobile • Tower • Derricks

7. Industrial Cranes • Overhead Cranes • Common in industrial facilities • Supported by overhead rails • Components • Bridge • Trolley • Hoist • Often pendant or remote operated • Easy to use, little training required, no stability problems

8. Industrial Cranes • Gantry cranes • Similar to overhead cranes, but supported by a mobile frame which travels on the ground Small (1000 – 10,000 pound capacity) gantry crane Large (600 ton capacity) gantry crane

9. Industrial Cranes • Jib cranes • Pivot mounted boom with trolley and hoist Floor-mounted jib crane Wall-mounted jib crane

10. Industrial Cranes • Power hoist • Usually electric or air operated • Chain hoist (or "chain fall") • Hand operated

11. Construction Cranes • Tower cranes • Variable height “climbing cranes” • Used for building construction

12. Construction Cranes • Mobile cranes • Crawler cranes • Truck cranes • Hydraulic cranes • Boom telescopes • May have jib • Equipped with outriggers for stability

13. Hydraulic Cranes

14. Hydraulic Cranes

15. Construction cranes • Derricks • Boom angle changes to adjust horizontal distance • Often used in shipyards, building construction, etc. • Gin pole • Chicago boom • Stiff-leg • Etc.

16. Mine-shaft rescue using a gin pole derrick improvised from an extension ladder Stiff-leg construction derrick

17. Hay derrick

18. Rigging • Rigging: The hardware and equipment used to safely attach a load to a lifting device • Wire rope • Usually a "core" member to increase flexibility • Fiber Core (FC) • Wire Strand Core (WSC) • Independent Wire-rope Core (IWRC)

19. Rigging • Fittings, sheaves • Shackles • Blocks • Sockets • Hooks • May have safety latch • Eyes • Turnbuckles

20. Rigging • Always use rigging to connect the load to the hook • Materials • Wire rope • Fabric • Chain • Slings • Straight (regular) • Choker • Basket • Double, triple, etc.

21. Rigging • Sling angle • Stress on sling legs varies with the angle • Divide the load by the number of sling legs, and divide by sin of the angle • For a two-legged sling, 2000 lb load and 60 degree, stress = 1155 lbs on the sling leg

22. Controlling Crane Hazards • Operators • 18 years old • Physical exam • Knowledge (training) • Estimating load weight • Signals • Operation • Skill (demonstration)

23. Controlling Crane Hazards • Inspection • Frequent • Daily, monthly • Hooks, rope, crane operation • Periodic • At least annually • Complete inspection - wear, damage, deterioration, operation • slings • Testing • Records

24. Preventing Crane Accidents • Contact with energized power lines (45% of accidents) • De-energize overhead lines • Maintain minimum distance • 10 feet distance for 50 kv • Over 50 kv, add 4 inches per 10 kv • Use proximity alarms • Warn when energized line is near • “No fatalities” in 25 years, according to mfg. • Warning signs • I-15 construction was a good example Sigalarm®

25. Warning label

26. Preventing Crane Accidents • Under hook lifting device problems • Inspect, proper use, etc. • Overturned cranes • Assure a level and stable base for the crane • Comply with load charts • Weight • Boom angle and extension • Only vertical loads • Wind can cause a significant side load

27. Load Chart • Load charts inside the cab include Structural capacity and tipping limits for the crane • Capacity is highest for short radius “over front” loads with outriggers extended.

28. Radius Rear Over Over Side Over Front 18.8' Boom 24' Boom 29.8' Boom 18.8' Boom 24' Boom 29.8' Boom 18.8' Boom 24' Boom 29.8' Boom 6 65,600* 65,600* 66,720* 8 57,250* 56,510* 57,250* 56,510* 61,150* 56,510* 10 50,760* 49,230* 47,060* 50,760* 49,230* 47,060* 52,520* 49,230* 47,060* 12 44,970 43,250* 41,310* 45,540* 43,250* 41,310* 46,390* 43,250* 41,310* 15 33,180 33,290 33,350 39,370 37,090 35,080 39,620 37,090 35,080 18 25,960 26,250 26,310 27,540 28,370 28,490 27,540 32,471 30,730 20 22,940 23,010 22,910 23,030 29,820 28,430 25 16,910 15,330 23,770 29 13,030 11,870 16,750 Load Chart

29. Preventing Crane Accidents • Dropped loads • Operating anti-two block device (upper limit switch) • Proper rigging • Inspection • Boom collapse • Inspection • Stable base • No overloading • No horizontal loading • Crushing by the counter weight • Stay away from the rear of the crane

30. Preventing Crane Accidents • Proper outrigger use • Level • Fully extended • Stable base • Use cribbing to distribute the load

31. Outrigger Use Outrigger with cribbing

32. Preventing Crane Accidents • Rigging failure • Inspection • Proper use • temperature, angles, etc. • Falls • Fall protection for workers suspended by crane "man basket" or "suspended work platform“

33. Links • Managing Mobile Crane Hazards • http://www.elcosh.org/en/document/96/d000104/managing-mobile-crane-hazards.html • Crane, Derrick, and Hoist Safety • http://www.osha.gov/SLTC/cranehoistsafety/index.html