Site Hazards & Risk Assessment Flashcards

What is the first step in a job site risk assessment for crane operations?

Answer: Conduct a site survey identifying all hazards including power lines, underground utilities, ground conditions, overhead obstructions, and proximity to structures

A comprehensive site survey identifies all potential hazards before the crane arrives. This includes overhead (power lines, structures), underground (utilities, voids), and surface (soft ground, slopes) hazards.

What underground hazard must be identified before setting up a crane?

Answer: Buried utilities (gas, electric, water, sewer) and underground voids or structures that could collapse under crane weight

Underground utilities can be ruptured by outrigger loads, and underground voids, basements, or tunnels can collapse. Utility locating (dial 811) and ground surveys are essential before crane setup.

How should ground bearing capacity be evaluated for crane setup?

Answer: Through engineering analysis of soil type, recent weather (saturation), fill vs. native soil, and proximity to excavations

Ground bearing capacity evaluation considers soil type, moisture content, fill material, proximity to excavations, underground structures, and freeze-thaw conditions. Engineering analysis may be required for heavy cranes.

What is the hazard of setting up a crane near an open excavation?

Answer: The excavation may have weakened the surrounding soil, which could collapse under the crane's weight causing the crane to tip

Excavations create zones of reduced soil strength. Crane loads near excavation edges can cause the wall to collapse, pulling the crane into the excavation. The angle of repose determines the safe setback distance.

Before a lift, what weather conditions should be assessed?

Answer: Wind speed and gusts, precipitation, lightning, visibility, and temperature extremes

All weather factors affect crane safety: wind (stability, load control), rain (visibility, ground conditions), lightning (electrical hazard), cold (brittle steel, ice), and heat (operator fatigue, hydraulic efficiency).

What is a 'critical lift' and what additional planning does it require?

Answer: A lift that exceeds 75% of rated capacity, involves hazardous materials, or passes over occupied areas — requiring a detailed, engineered lift plan

Critical lifts have higher consequences of failure. They require an engineered lift plan, review by a qualified person, pre-lift safety meeting, increased monitoring, and contingency procedures.