Selecting Fall Protection Anchorage Points
description
Transcript of Selecting Fall Protection Anchorage Points
SELECTING ANCHORAGE POINTSLJB WEBINAR SERIES: MAY 2013
THOM KRAMER, P.E., C.S.P. – LJB INC.
(937) 259-5120; [email protected]
BOTTOM LINE UP FRONT
Just because your anchorage won’t fail doesn’t mean it is
safe.
Our focus on what people tie off to needs to catch up with
our focus on getting workers to tie off.
ACTION PLAN
1. Use the worksheet to evaluate 5-10 anchorages that you
know are used in your organization
• Temporary and permanent
2. Identify 2-3 systems where you can use the worksheet to
plan systems
Anchorage Worksheet
ADEQUATE ANCHORAGE?
ADEQUATE ANCHORAGE?
ADEQUATE ANCHORAGE?
AGENDA
Anchorages 101
Selection criteria
Exercise
Closing
ANCHORAGE TYPES
Fall arrest Work positioning Travel restraint
Horizontal lifeline Rescue
ANSI DEFINITIONS
Designed by a Qualified Person
Must be used for HLL
CertifiedDesignated by a Competent Person
Unquestionably strong elements
Non-Certified
CERTIFIED ANCHORAGES
Fall Arrest
Work Positioning
Travel Restraint
Horizontal Lifeline Rescue
2 x MAF2 x
foreseeable force
2 x foreseeable
force2 x cable tension
5 x applied
load
Designed by a qualified person
NON-CERTIFIED ANCHORAGES
Fall Arrest
Work Positioning
Travel Restraint
Horizontal Lifeline Rescue
5,000 lbs. 3,000 lbs. 1,000 lbs. N/A 3,000 lbs.
Designated by a competent person
ANSI I-14.1 ANCHORAGE DESIGN LOADS
PERSONAL FALL ARREST SYSTEM:
5,000 pounds per employee attached
Designed, installed and used as part of a complete
PFAS which maintains a safety factor of at least 2
EQUIPMENT TIEBACK:
Capable of supporting at least 5,000 pounds
AGENDA
Anchorages 101
Selection criteria
Exercise
Closing
CONSIDERATIONS
Hierarchy of control
> Is there another way?
Structural capacity
Fall clearance
Number of users
Environmental conditions
ANCHORAGE STRENGTH
ANCHORAGE DESIGN/SELECTION
UnquestionablyStrong
Everything in between
Clearly Inadequate
ANCHORAGE DESIGN/SELECTION
Unquestionably strong?
VARIABLES TO CONSIDER
Span and size of member
Material(s)
Additional loads
Supports
Deterioration and corrosion
Anchorage location and spacing > Above dorsal D-ring
STRUCTURE OF ANCHORAGE
Existing members of a building structure are often used as anchorages
Existing members usually support existing loads> Beam
> Purlin
> Truss
STRUCTURE OF ANCHORAGE
Addition of a fall arrest load may constitute a change in use
Many jurisdictions require individuals to be professional engineers who design and evaluate physical structures
DESIGN LOADS
Permanent loads> Roofing> Piping> Mechanical equipment
Transient (temporary) loads> Occupancy> Storage> Wind> Snow
DESIGN LOADS
Conditional use> Incorporates an administrative control that allows certain
members to be used as an anchorage under specific conditions
> Applies to transient loads> Combines two methods identified within the fall protection
hierarchy – fall arrest and administrative controls> Existing building members used as conditional use
anchorages must be strictly controlled by a qualified person
SAFE ATTACHMENT LOCATIONS
Analysis may show that parts or all or none of the beam may be used for anchorage
Requires strict control by a qualified person
Beams
3 Foot Max. Safe Zone
SAFE ATTACHMENT LOCATIONS
Panel points – the intersection of horizontal, vertical and diagonal members (analysis required)
Individual members are usually not adequate
Trusses
FALL CLEARANCE
Rules of thumb
> Energy-absorbing lanyard – 13’
> Self-retracting lanyard – 7’
> Greater if determining
anchorage height
SWING FALL
Anchorage needs to be
maintained overhead
> Within 15º of vertical
NUMBER OF USERS
Anchorage designed to support specific load
Load for a certified system is determined by the qualified person
Based on number of users and maximum arresting force of energy-absorbing lanyard
NUMBER OF USERS
Procedures should include:
> Maximum number of permitted simultaneous users
> Maximum user weight
> Maximum arrest force of energy-absorbing lanyard
Location of anchorage directly affects fall clearance requirements
Clearances are calculated by qualified person
ENVIRONMENTAL CONDITIONS
May affect longevity of permanently installed equipment
Components installed in these conditions should be fabricated from non-corrosive materials
Steelwork fabrications can be painted or galvanized
ENVIRONMENTAL CONDITIONS
Severe environmental conditions may warrant use of stainless steel
Take precautions to avoid bi-metallic corrosion which
occurs when dissimilar metals are placed in contact
with each other
INSTALLATION CONSIDERATIONS
Consider anchorage connector location and framing of supporting anchorage before installing
Consider fall protection for the person installing the system
AGENDA
Anchorages 101
Selection criteria
Exercise
Closing
EXERCISES
Select new anchorage with existing structure
Select anchorage for new structure (PtD)
EXERCISE: EXISTING STRUCTURE
Anchorage Worksheet
EXERCISE: NEW STRUCTURE
Anchorage Worksheet
USE YOUR RESOURCES
ACTION PLAN
1. Use the worksheet to evaluate 5-10 anchorages that you
know are used in your organization
• Temporary and permanent
2. Identify 2-3 systems where you can use the worksheet to
plan systems
SELECTING ANCHORAGE POINTSLJB WEBINAR SERIES: MAY 2013
THOM KRAMER, P.E., C.S.P. – LJB INC.
(937) 259-5120; [email protected]