An Evaluation of Supported Scaffold Safety

Fatal Falls from Supported Scaffolds, 1992-98

• Total # of deaths = 267 (38/year)
  
  
  • 217 falls (81%)
    
  • 47 collapses (18%)
    
    
• 15 deaths (6%) dismantling scaffolds
  
• 6 deaths (2%) assembling scaffolds
  

Source: U.S. Bureau of Labor Statistics data

Research Methods

• Used a 150-point checklist to evaluate scaffold safety practice
  
  
  • Rated scaffolds as acceptable or unacceptable
    
    
• Evaluated 113 scaffolds in 9 areas of Eastern U.S.
  
• Also evaluated information on worksite, workforce, and scaffold competent person.

Results

• 36 of the 113 scaffolds (32%) were unacceptable and posed imminent hazards:
  
  
  • danger of collapse
    
  • missing planking, guardrails, and/or
    
  • inadequate access
    
    
• 77 scaffolds (68%) were acceptable and posed no imminent danger to the workers.

30 Scaffolds (27%) Had Structural Flaws

Missing or improperly supported base plates	17
Scaffold not tied properly to building	13
Platform not level	6
Some runners missing	3
Some jacks overextended	2
Severe overloading	2
Some posts incorrect	1
Some braces not tight	1

36 Scaffolds (32%) Had Fall Hazards

		# fall hazards
Missing mid guardrails		33
Missing top guardrails		28*
	* Also missing midrails
Improper access
	Climbing scaffold frame	23
	Other severe access problems	5
Partially planked platforms		26
Substandard planks		3

Correlation between Structural Flaws and Fall Hazards

• 36 scaffolds were unacceptable
  
• 23 had both structural flaws and fall hazards
  
• 10 had fall hazards only
  
• 3 had structural flaws only

Problems of Unacceptable Scaffolds

• 36 scaffolds were unacceptable
  
  
  • 92% were missing guardrails
    
  • 83% had structural flaws
    
  • 78% had poor access
    
  • 72% were insufficiently planked

Scaffold Competent Person

• Required by OSHA
  
  
  • 29 CFR 1926.451(f)(3) requires inspections by competent person before each work shift and after occurrences which could affect scaffold structural integrity
    
    
• Competent person
  
  
  • Recognize hazards
    
  • Authorized to take corrective action
    

Competent Persons on Scaffold Sites

• 104 sites had workers present
  
• 82 (79%) had competent persons
  
• 10 sites (10%) said competent person was not present
  
• 72 competent persons were interviewed
  
  
  • Only 32 (44%) had scaffold safety training

Need for Competent Person Scaffold Safety Training

• 32 sites had competent persons who had scaffold safety training
  
  
  • 25 scaffolds (78%) were acceptable
    
    
• 62 sites had no competent person or had one without scaffold safety training
  
  
  • 24 scaffolds (39%) were acceptable

Importance of Scaffold Erector

• 72 scaffolds erected by scaffold user
  
  
  • 43 (60%) were acceptable
    
    
• 41 scaffolds erected by scaffold erection contractor
  
  
  • 34 (83%) were acceptable

Effect of Union Status of Scaffold Erector

• 49 scaffolds erected by union contractors
  
  
  • 38 (78%) were acceptable
    
    
• 64 scaffolds erected by non-union contractors
  
  
  • 39 (61%) were acceptable

Effect of Type of Supported Scaffold

• 86/113 scaffolds (76%) were frame scaffolds
  
  
  • 54 frame scaffolds (63%) were acceptable
    
    
• 27 scaffolds (24%) were other types of scaffolds
  
  
  • 23 other scaffolds (85%) were acceptable

Summary of Proper Scaffold Safety Practice -1

• Unacceptable scaffolds have both:
  
  
  • Structural flaws
    
    
    • Missing or improperly supported base plates
      
    • Improper tying off to building
      
    • Uneven platform slope
      
      
  • Fall protection hazards
    
    
    • Missing planking and/or guardrails
      
    • Inadequate access

Summary of Proper Scaffold Safety Practice - 2

• Strong correlations with:
  
  
  • Presence of competent person with scaffold safety training
    
  • Use of non-frame scaffolds
    
  • Scaffold erected by scaffold erection company
    
    
• Slightly weaker correlation with union status of scaffold erector

Summary of Proper Scaffold Safety Practice - 3

• No correlation with:
  
  
  • Location n Site size
    
  • Number of workers on the scaffold
    
  • Trade of scaffold workers

Recommendations

• Hire an outside scaffold erector
  
• Have competent person on site who has had scaffold safety training
  
• Consider whether frame scaffolds are the best choice
  
• Perform regular inspections

Quick Scaffold Inspection Checklist

• Check for missing planks on platforms
  
• Check for missing guardrails
  
• Check for proper access
  
• Check for proper tying off to buildings
  
• Note: The first 3 points find 92% of unacceptable scaffolds
  

Missing Planks



Missing Guardrails



Improper Access



Further Information on Construction Safety and Health

CPWR – Center for Construction Research and Training www.cpwr.com

This presentation was funded by research grant U60 CCU 317202 from the National Institute for Occupational Safety and Health (NIOSH) through CPWR – Center for Construction Research and Training, Silver Spring, Md. The contents are solely the responsibility of the authors and do not necessarily represent the official views of NIOSH.