Safety and Jobsite Practices
Safety items on this exam are practical: excavation protection, confined spaces, electrical work, rigging, and dust. They reflect MIOSHA rules that adopt federal construction standards, and they are written as scenarios, not slogans.
Excavations and confined spaces
- Trenches 5 ft deep or more need a protective system: sloping, shoring, or shielding. A competent person inspects before entry and as conditions change.
- Keep spoil and equipment at least 2 ft back from the edge, provide a ladder within 25 ft of travel, and never enter a well pit or vault without testing the atmosphere and following permit-required confined-space procedures.
- Assume a pit can hold heavier-than-air gas or be oxygen-deficient; ventilate and test before entry.
Rig, electrical, and health hazards
- Maintain required clearance from overhead lines; treat any contact as an emergency and keep others away.
- Ground pump motors and controls, use GFCI protection, and lock out power before servicing.
- Inspect wire rope, shackles, and slings; keep hands and loose clothing clear of the rotary table and hoist.
- Control silica dust from drilling and cutting with water or respiratory protection, and protect hearing near the rig and compressor.
Worked example
A crew must dig a 6-ft pit for a pitless installation in Type C sandy soil. Reasoning: the depth exceeds 5 ft, so a protective system is required. The crew slopes the walls to about 1.5 to 1 horizontal to vertical, sets spoil 2 ft back, provides a ladder, and has the competent person inspect before anyone enters.
Traps
- Treating a shallow well pit as exempt from confined-space rules because it is small.
- Standing spoil at the trench edge, adding surcharge load.
- Servicing a pump without lockout and without verifying the circuit is dead.