safety in excavation is 3764 : 1992 excavation excavation excavation. any man made cut, cavity or...
TRANSCRIPT
Safety in Excavation
IS 3764 : 1992
EXCAVATION
ExcavationExcavation.
Any man made cut, cavity or depression in the earth’s surface formed by earth.
•Soil Collapse
•Utilities
•Hazardous atmospheres
•Adjacent structures
•Falls / Falling loads
•Access / Egress
•Vehicle traffic
•Mobile equipment
•Water accumulation
•Cave-in
Excavation Hazards
Cave-in / Soil collapse
Improper shoring.
…..Excavation hazards
Collapse of shoring
Falling loads
Excavation hazards
Slip & fall of workmen
Utilities
…..Excavation hazards
Adjacent structures
…..Excavation hazards
Vehicular traffic
Access / Egress
Mobile equipment.
…..Excavation hazards
Soil collapse
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
•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
Soil Classification
Preventing Soil CollapseSoil classification (Type a, b, or C)
• Sloping • Benching• Placing a shield.• Shoring(Timber / Aluminum shoring• Sheet piling
Your choice of protection
•Sloping
•Benching
•Shoring
•Shields
Designed by a Registered Project Engineer
Simple Sloping
Short term up to 12’ -630
•Stable Rock : 900
•Type A - 3/4:1530
Note :Greater than 20 feet deep shall be designed by a registered
professional engineer.
Simple Sloping -Type A Soil
Unsupported Vertically-Sided Lower Portion <12 ft
Unsupported Vertically-Sided Lower Portion <8 ft
Supported or Shielded Vertically-Sided Lower Portion
Simple Sloping -Type A Soil
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.
Benching
Type A
Type B (cohesive)
OUTWARD SLOPE ( 35* TO 40*) CONSIDERING ONGOING RAINY SEASON
SUPPORT TO THE WALL OF
EXCAVATED PIT
Timber Shoring Installations
REFER TO DESIGN ENGR.
UtilitiesUnderground
PERMIT SYSTEM
ABOVE GROUND UNDER GROUND
EXPLOSION FIRE
UTILITIES
PREVENTIONObtain work permit and get clearances
from the concerned Electricity Water & Sewage Pipeline Communication Oil & Gas Pipe Line
Use Detectors ( for More Reliable)
Water Accumulation
Ground waterSurface water
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)
Adjacent Structures
Ensure structure stabilityShoringBracingEvaluation by
Professional
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.
Access
–Ladders –
•@ 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
Vehicle Traffic
Control Measures
• Traffic Management Plan• Traffic Control• Traffic Safety Vests• Fencing • Illumination
FencingHard 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 diversionsPedestrian walkway diversions
Reflective Cone Barricades
Caution Signs
Temporary Lightings:
Sufficient Area Lighting.
Emergency Lighting with Power back up.
ILLUMINATION
Excavation InspectionsDaily 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
Safety awareness – SupervisionDevelope - 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,
Any Questions ?