1. Safety in Excavation

2. EXCAVATION
Reference Standard
IS : 1992

3. Excavation Excavation.
Any man made cut, cavity or depression in the earth’s surface formed by earth.

4. Excavation Hazards Soil Collapse Utilities Hazardous atmospheres
Adjacent structures
Falls / Falling loads
Access / Egress
Vehicle traffic
Mobile equipment
Water accumulation
Cave-in

5. …..Excavation hazards
Cave-in / Soil collapse
Improper shoring.

6. Excavation hazards
Collapse of shoring
Falling loads

7. …..Excavation hazards
Slip & fall of workmen
Utilities

8. …..Excavation hazards
Vehicular traffic
Adjacent structures

9. …..Excavation hazards
Mobile equipment.
Access / Egress

10. Soil collapse

11. So, What is required ?

12. Prior to Excavation Obtain a work permit Check Ground / Soil condition
Check Ground / Surface Water
Check the Location of Water Table
Check Under ground / Overhead utilities
Adjacent buildings
Dynamic load / Traffic

13. Soil Classification Type A : Clay, sandy clay, clay loam Type B :
Angular gravel (similar to crushed rock), silt, silt loam, sandy loam
Type C:
Gravel, sand, loamy sand,Submerged soil or soil from which water is freely seeping; or Submerged rock that is not stable

14. Preventing Soil Collapse
Soil classification (Type a, b, or C)
Sloping
Benching
Placing a shield.
Shoring(Timber / Aluminum shoring
Sheet piling

15. Your choice of protection
Sloping
Benching
Shoring
Shields
Designed by a Registered Project Engineer

16. Simple Sloping Stable Rock : 900 Type A - 3/4:1 530
Short term up to 12’ -630
Note :Greater than 20 feet deep
shall be designed by a registered
professional engineer.

17. Simple Sloping -Type A Soil
Unsupported Vertically-Sided Lower Portion <12 ft
Unsupported Vertically-Sided Lower Portion <8 ft

18. Simple Sloping -Type A Soil
Supported or Shielded Vertically-Sided Lower Portion

19. Simple Sloping Type B - 1:1 450 Type C - 1½ :1 340
Note :Greater than 20 feet deep shall
be designed by a registered
professional engineer.

20. Benching
Type A
Type B
(cohesive)

21. Basic components of shoring

22. Shoring in Footing foundation
OUTWARD SLOPE ( 35* TO 40*) CONSIDERING ONGOING RAINY SEASON

23. Arrangements in Water Logged Area
SUPPORT TO THE WALL OF EXCAVATED PIT

24. Timber Shoring Installations
REFER TO DESIGN ENGR.

25. Utilities
Underground
PERMIT SYSTEM

26. EFFECTS OF UTILITIES
ABOVE GROUND
UNDER GROUND

27. EFFECTS OF UTILITIES
EXPLOSION
FIRE

28. UTILITIES Obtain work permit and get clearances from the concerned
PREVENTION
Obtain work permit and get clearances from the concerned
Electricity
Water & Sewage Pipeline
Communication
Oil & Gas Pipe Line
Use Detectors ( for More Reliable)

29. Water Accumulation
Ground water
Surface water

30. Hazardous Atmospheres
Never Start Work if,
Oxygen Level less than 19.5 %
Permissible limit of the toxic gases exceeded.
More than 20 % of Lower Explosive Limit.
PRECAUTIONS
Ventilation to over come the above said.
Blocking the source, incase of toxic and flammable gases.
(Using other effective controls to reduce the level of atmospheric contaminants to acceptable levels)

31. Adjacent Structures Ensure structure stability Shoring Bracing
Evaluation by Professional

32. FALLING LOAD Gravity Weight of soil pile Weight of near by structures
Weight of personnel &equipment
Vibration
PREVENTION
Never operate a construction equipment within 2.5 m from the edge of the excavation.
Stacking the material 1 Meter away from the edge of the excavation.

33. Access Ladders – Ramps with slope not more than 15o
@ every 9.14 m Length – Normal Operations
@ every 4.6 m length – Hazardous operation
Ramps with slope not more than 15o
Stairs cut on earth

34. Vehicle Traffic Control Measures Traffic Management Plan
Traffic Safety Vests
Fencing
Illumination

35. Traffic Control Device & Vest

36. Fencing Physical barricades required always
Hard Barrication shall be provided, in the fall prone areas and if depth is more
Physical barricades required always
Must be placed 2m away from excavation edge.
Standard fall protection required for vertical falls over 1.3m
Traffic diversions
Pedestrian walkway diversions

37. Caution Signs
Reflective Cone
Barricades

38. ILLUMINATION Temporary Lightings: Sufficient Area Lighting.
Emergency Lighting with Power back up.

39. Excavation Inspections
Daily Inspections by Competent Person
Start of shift, as needed, following rainstorms or other hazard-increasing event
Possible cave-ins
Protective system failure
Water accumulation
Hazardous atmospheres

40. Beyond All

41. Safety awareness – Supervision
Develope - personnel interested on Safety,
Safe work procedures considering the ground realities.
Awareness and motivating the supervisors concerned,
Develop system to report, analyze and prevent Near-miss cases.
Developing gang leaders and attitude,

42. Any Questions ?

43. Thank You
&
Have a Safe day