Protective Systems
At what depth is a means of access/egress required?
4ft
1926.651(c)(2)
Means of egress from trench excavations. A stairway, ladder, ramp or other safe means of egress shall be located in trench excavations that are 4 feet (1.22 m) or more in depth so as to require no more than 25 feet (7.62 m) of lateral travel for employees.
Describe Type A soil.
A soil is cohesive and has a high unconfined compressive strength; 1.5 tons per square foot or greater. Examples of type A soil include clay, silty clay, sandy clay, and clay loam.
Who do you need to call prior to digging?
811
At a minimum, how far away must spoil piles be kept from the edge of an excavation?
2ft
1926.651(j)(2)
Employees shall be protected from excavated or other materials or equipment that could pose a hazard by falling or rolling into excavations. Protection shall be provided by placing and keeping such materials or equipment at least 2 feet (.61 m) from the edge of excavations, or by the use of retaining devices that are sufficient to prevent materials or equipment from falling or rolling into excavations, or by a combination of both if necessary.
Describe Type C soil.
Type C soil is the least stable type of soil. Type C includes granular soils in which particles don't stick together and cohesive soils with a low unconfined compressive strength; 0.5 tons per square foot or less. Examples of Type C soil include gravel, and sand. Because it is not stable, soil with water seeping through it is also automatically classified as Type C soil, regardless of its other characteristics.
When does an excavation need to be inspected?
Pre-shift inspection by competent person and after an environmental event (ex. rain storm).
What are the 3 types of protection?
Sloping, Shoring and Shielding
Who is allowed to classify soil types?
Competent Person
What is the lateral travel distance requirement for access egress in a trench?
Every 25'.
At what depth do excavations require protection?
5ft
Sloping / benching of sides to allowable configurations and slopes as per soil type.
Shielding (i.e. trench boxes) or shoring which shall have the manufacturer’s tabulated data and specifications—or a professional engineer stamp—and current annual inspection documentation; all the aforementioned must be on site.
Using a slope or shield system designed by a registered professional engineer.
Refer to 29 CFR Subpart P, Appendix B.
What two tests must be done to classify soils other than Type C?
One Visual & one Manual
What is the color coding for an electrical utility marking?
Red
At what depth is engineering required for excavation protective systems?
Greater than 20'.
If water is seeping through, what is the soil type?
Type C
Because it is not stable, soil with water seeping through it is also automatically classified as Type C soil, regardless of its other characteristics.
At a minimum, what must all new permanent & temporary utilities be installed with?
Detectable Underground Warning Tape is used for detecting, locating, identifying and protecting buried utility lines for gas, water, sewer, telecommunication and electrical markets.