A mobile crane with a 150-foot boom is being used near overhead power lines carrying 25,000 volts. What is the minimum required clearance distance?
Correct Answer
A) 20 feet
For power lines carrying over 20,000 volts but less than 50,000 volts, OSHA requires a minimum clearance of 20 feet for crane operations. Higher voltage lines require greater clearance distances to prevent electrical hazards.
Why This Is the Correct Answer
According to OSHA 1926.1408, when operating cranes near power lines carrying between 20,001 and 50,000 volts, a minimum clearance of 20 feet must be maintained. The 25,000-volt power line in this scenario falls within this voltage range. This clearance distance applies to any part of the crane or its load, including the boom, and is critical for preventing electrical contact that could result in electrocution or equipment damage.
Why the Other Options Are Wrong
Option B: 25 feet
15 feet is not a standard OSHA clearance distance for any voltage range and would be insufficient for 25,000-volt power lines.
Option D: 10 feet
25 feet is the minimum clearance required for power lines carrying between 50,001 and 200,000 volts, which exceeds the 25,000 volts in this scenario.
Memory Technique
Use '20-20-20': 20,000+ volts requires 20 feet clearance (up to 50,000 volts). The voltage and clearance both contain '20' as key numbers.
Reference Hint
OSHA 1926 Subpart CC - Cranes and Derricks in Construction, specifically section 1926.1408 dealing with power line safety
More Project Mgmt Questions
What is the minimum R-value required for wall insulation in Florida Climate Zone 2?
A subcontractor brings a new chemical product to your jobsite. Under the Globally Harmonized System (GHS), what information must be immediately available to workers?
A construction site has a trench that is 8 feet deep in Type B soil. What is the maximum allowable slope ratio for the trench walls without protective systems?
What is the maximum recommended spacing between drywall screws when attaching to wood studs?
Your crew discovers suspected asbestos-containing materials during a renovation project. What is the first action you should take?
A scaffold platform is 12 feet long and 5 feet wide. If the maximum load capacity is 25 pounds per square foot, what is the total weight capacity of this platform?
Which CSI MasterFormat Division would contain specifications for fire-stopping and firesafing materials?
In tilt-up concrete construction, what is the primary advantage of this method over conventional cast-in-place construction?
Which OSHA standard specifically addresses construction industry safety and health regulations?
A structural drawing shows a beam labeled 'W12x26'. What does the '26' represent?
People Also Study
Business & Financial Management
120 questions · 70% to pass
Contract Administration
60 questions · 70% to pass