The document discusses excavation safety. It notes that excavating is one of the most hazardous construction operations, with cave-ins posing the greatest risk and often resulting in fatalities. OSHA regulations require protective systems like sloping, shielding, or shoring for trenches over 5 feet deep. A competent person must inspect sites and determine the appropriate protection. Proper ingress/egress, atmospheric testing, and following basic rules can help prevent accidents and save lives. Pre-planning is critical to excavation safety.

1. Employee
Safety Series
Excavating is recognized as one of the most
hazardous construction operations.
Source: OSHA revised Subpart P, Excavations, of 29 CFR 1926.650, 29 CFR
1926.651, and 29 CFR 1926.652
An excavation is…any man-made cut, cavity,
trench, or depression in an earth surface
formed by earth removal.

2. Cave-ins… pose the greatest risk and are much more likely than
other excavation-related accidents to result in
worker fatalities.
• Two workers are killed every month.
• U.S. Bureau of Labor Statistics (BLS) data show that
271 workers died in trenching or excavation cave-
ins from 2000 through 2006.
• Per NIOSH-488 deaths, 1992 and 2000. Averaging 54
fatalities each year.
• More than half of those killed are coworkers, fire
dept. personnel & bystanders attempting to rescue.
[29 CFR 1926.32(f)]

3. OSHA Trenching and Excavation
29 CFR 1926.651
• Trenches 5 feet (1.5 meters) deep or greater
require a protective system.
• Exception is solid, stable rock.
• Less than 5 feet deep, a “competent person”
will decide if a protective system is needed.
• Who is a “Competent Person” ?

4. Per OSHA, a "competent person" is defined
as "one who is capable of identifying existing
and predictable hazards in the surroundings
or working conditions which are unsanitary,
hazardous, or dangerous to employees, and
who has authorization to take prompt
corrective measures to eliminate them”.
The standard does not specify particular training requirements for
the competent person. It is a critical roll, because they evaluate &
determine the safety of the excavation or trench others will enter.

5. Excavation Safety Checklist
Contractor________________ Competent Person_________________ Dimensions____________
Rescue Equipment__________
Date______________ Location____________ Intersecting__________ Miss Utility__________
COMPETENT PERSON CHECKLIST
•This inspection: Start of day____________, During shift_________________ Hazard increasing
occurrence________________________
•Inspection: Excavation: _____________________, Adjacent Area____________ Protective systems________________, Surface
Encumbrances____________ Underground Utilities______________, Spoil Pile________________
Equipment_______________________, Other___________________ Access & Egress__________________,
Vibrations________________
•Vehicular Traffic: Vest_______________, Warning Lights___________________ Mobile Warning
Equipment___________________________
•Hazardous Atmospheres: Explosive_____, Flammable_____, Corrosive_____, Oxygen Deficient_____, Poisonous_____,
Toxic_____, Irritating_____, Oxidizing_____, Other_____
•Water Accumulation: Removal__________, Prevent surface run off__________, Method__________, Forecast__________
•Soil Classification: Soil classification used____________, Soil type__________, Visual test__________, Manual
test____________ Tabulated data on site______________, Copy of standard_________
•Protective Systems: Sloping__________, Benching__________, Shoring__________, Trench Box__________, Aluminum
Hydraulic__________, Other_______________, Manufacturers Data _____________ Timber______________
Maryland Fire and Rescue Institute Susan Harwood Grant SH-16582-07
Source: https://www.osha.gov/dte/grant_materials/fy07/sh-16582-07/competent_person_checklist2.pdf
Employee
Safety Series

6. Ingress and Egress
• In trenching and excavation operations, ingress and
egress means a way for employees to enter or exit
an excavation or trench, such as a ladder or ramp.
• Trenches deeper than 4 feet MUST be provided with
a fixed means of egress, such as secured ladder.
• Spacing between ladders must be 25 feet or less to
the nearest means of egress.
• Ladders must be secured and extend a minimum of…
3 feet above the landing.
Secure ladders to prevent displacement. At the top, nail the ladder or lash it with wire or rope
to a secure object. At the bottom, secure it against movement by blocking, tying or another
suitable method. (National Safety Council Data Sheet I-568 Rev. June 2006”)

7. Protective Systems-3 Types
• Sloping (or benching) involves cutting back the
trench wall at an angle inclined away from the
excavation.
• Shoring requires installing aluminum hydraulic or
other types of supports to prevent soil movement
and cave-ins.
• Shielding protects workers by using trench boxes or
other types of supports to prevent soil cave-ins.
The protective system type shall be determined by a
“Competent Person” who will test the soil both
manually and visually.

8. Sloping & Benching
Sloping inclines away
from the excavation.
Benching is dug in stair
like levels.

9. Shoring
Install aluminum,
hydraulic
supports…
…or other types of
supports such as
timber.

10. Shielding
Protects workers by using trench boxes.
Photo: Courtesy of Virginia Department of Labor & Industry-2011 Trenching and Excavation - PSA
http://www.doli.virginia.gov/agency/youtube_psa_gallery.html

11. The Dirty Facts
• OSHA Classifies Soil Types as A, B, C…or solid rock.
• 1 cubic foot of soil can weigh from 100-125 lb.
• The weight of 1 cubic yard of soil can weigh 2700-
3000lbs. Water adds weight.
• A typical trench collapse involves three to five cubic
yards of soil, or about 6,000 to 20,000 pounds!
• An excavation wall shearing off, can happen as fast as
45 mph.
Would you risk being hit by a car going 45mph?
A cubic yard of soil shearing off onto a worker,
has the same impact.

12. • You play a critical role in keeping the jobsite safe.
• Each excavation is different and can change at any
moment causing cave ins to happen without
warning.
• All related injuries and fatalities can be prevented.
• Most cave ins were a result of poor or no pre-
planning.
• Too many are caused by not strictly adhering to the
OSHA standard, job site safety rules and company
procedures. One cave in is too many.

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14. Basic Excavation Rules
• Know where underground utilities are located
before digging.
• Keep excavated soil (spoil) and other materials at
least 2 feet from trench edges.
• Test for atmospheric hazards such as low
oxygen, hazardous fumes & toxic gases > 4’
• Remove or minimize all surface obstacles at the
worksite that may create a hazard
• Identify other sources that might affect an
excavations stability.
Traffic Vibration… Disturbed soil… Multiple contractors

15. • Inspect excavations before you start each day/shift.
• Inspect again after rain or any occurrence that could
have changed conditions & excavation integrity.
• Never work under suspended or raised loads.
• Wear high visibility/reflective clothing when
exposed to traffic.
• Install proper warning signs & barricades.
• Keep heavy equipment away from trench edges.
More Basic Excavation Rules

16. Gas Related Hazards
• Accidental PE line punctures or ruptures
• Leaking Gas
• Confined Space
• Asphyxiation
• Pigging or purging hazards
• Static Electricity
• Fire/Explosion

17. Excavation Emergencies
• Hazardous effects include compression and
asphyxiation. (Crushing effects=organ failure)
• Typical extrication can take one to seven
hours.
• 60% of fatalities are
would-be rescuer as
well as the person
originally in danger.
Source: Virginia Tech-http://www.ehss.vt.edu/programs/EXC_emergencies.php

18. Rescue Workers Training
• Excavation and Trenching Safety
• Natural Gas Awareness
• Gas Fire Fighting Techniques
• Joint Emergency Action Plans
• Contractor Town Hall Meetings
• General Public Services Messages
Pre-planning Saves Lives !

19. The Investigation
OSHA, District Attorney, Company Rep & Media

20. Without Warning

21. 2015-Too Late for Two

22. Preparation saves lives: 12 critical questions
• 1. Have all underground utilities and their estimated locations been accounted for
(sewer, telephone, fuel, electric, water lines)? [29 CFR 1926.651(b)]
• 2. Is there proper access and egress? [29 CFR 1926.651(c)]
• 3. Will there be vehicular traffic exposure near the excavation? [29 CFR
1926.651(d)]
• 4. Is there proper protection from exposure to falling loads? [29 CFR 1926.651(e)]
• 5. Is there a warning system for mobile equipment? [29 CFR 1926.651(f)]
• 6. Is there a potential for exposure to hazardous atmospheres?[29 CFR
1926.651(g)]
• 8. Will the excavation be near existing structures? If so, what is the stability of the
adjacent structures? [29 CFR 1926.651(i)]
• 9. What types of soil will be found?
• 10. Is there adequate protection from loose rock or soil? [29 CFR 1926.651(j)]
• 11. If a protective system is needed, what type of system is adequate? [29 CFR
1926.652(a)]
• 12. If employee exposure to any hazard is anticipated, is there a plan in place to
perform daily inspections of excavations, adjacent areas and protective systems?
[29 CFR 1926.651(k)]

23. Safety Begins
With YOU !

24. We Need You
And So Do They
Employee
Safety Series