On the Safe Side: Installation of Metal Decking and Fall Hazards

The installation of floor and roof decking continues to be one of the “deadly dozen hazardous activities that lead to fatalitiesand disabling injuries."  The focus of this safety bulletin is to highlight the common hazards during the decking process that, historically, have produced the highest percentage of fatalities and disabling injuries.  Incident trends and investigative reports clearly indicate the primary causation factors are stemming from the same common hazards during metal decking installation.

The Importance of Training

Prior to performing the installation of metal decking, apprentices and journeymen must be trained on the recognition and avoidance of common hazards during the installation process to prevent serious incidents.  The OSHA Subpart R - Steel Erection standard requires special training for all Ironworkers working within a Controlled Decking Zone (CDZ).  The OSHA 1926.760(c)(3)(i) requires training on “the nature of the hazards associated with work within a controlled decking zone” and additionally, the OSHA 1926.761(c)(3)(ii) standard requires training on “the establishment, access, proper installation techniques and work practices.”    

Preventing Fall Hazards From Lack of Sheet End-Bearing and Lap Splicing

When decking sheets are placed during the progression of leading edge installation, both ends of the sheets must have sufficient end-bearing on structural support to prevent sheet deflection and collapse.  When decking sheets are placed in their final position, the male-female lap splices must be inter-locked to prevent the sheets from sliding open. Walking and working on metal decking sheets with insufficient end bearing on structural members and sheets that have not been properly lap spliced along the leading edge has been attributed to fatalities and serious incidents from falls through the sheets.     

Ensure end bearing and lap-splicing.
Ensure end bearing and lap-splicing.

Preventing Perimeter and Interior Fall Hazards

Perimeter and fall hazards created by open-sided floors have attributed to fatalities and serious incidents during the decking process. The OSHA 1926.760(a)(2) standard requires “on multi-story structures, perimeter safety cables shall be installed at the final interior and exterior of the floors as soon as the metal decking has been installed.”   However, in some areas throughout the country, it is a common practice for the safety cables to be installed prior to the decking process.  The OSHA standard 1926.756(e)(2)requires  “perimeter columns shall have holes or other devices in or attached to perimeter columns at 42 – 45 inches above the finished floor and the midpoint between the finished floor and the top cable to permit installation of perimeter safety cables except where constructibility does not allow.” 


Exterior cable lugs installed prior to column erection.

Perimeter Fall Hazard

The Ironworker on the right was exposed to an exterior fall hazard due to the lack of perimeter safety cables.   The steel erection contractor and steel fabricator prearranged for holes to be punched in column flanges for the installation of cables.  The perimeter safety cables must be installed after the decking has been installed.


Lack of perimeter safety cables.

Interior Fall Hazard

The Ironworker installing flashing around the interior shaft opening is exposed to an interior fall hazard to the basement of the building.  Detail work such as flashing must not proceed until all interior floor openings have been guarded by protective covers or standard guardrail systems.


Lack of interior safety cables around opening.

Prevent Floor Opening Hazards

The installation of metal decking around stairways, elevator shafts, and other openings create fall hazards.  The OSHA 1926.754(e)(2)(ii) standard requires “roof and floor openings shall be covered during the decking process.  Where the structural design does not allow openings to be covered, they must be protected by perimeter safety cable systems, guardrail systems, safety net systems, or personal fall arrest or fall restraint systems.”  If covers such as plywood are used, the OSHA 1926.760(d)(1)(ii) standard requires “covers shall be capable of supporting, without failure, twice the weight of employees, equipment and materials that may be imposed on the cover at any one time.”

Requirements for Maintaining Tightly Decked, Planked, or Netted Floors

During the erection of multi-story structures, the installation of decking, planking, or nets must be integrated into the erection sequence to limit fall hazards and prevent falling object hazards to workers below.  The OSHA Subpart R – Steel Erection standard 1926.754(b)(3) requires “a fully planked or decked floor nets shall be maintained within two stories or 30 feet, whichever is less, directly under any erection work being performed.”   Unfortunately, there has been much confusion regarding this OSHA standard due to the OSHA CPL 02-01-048 Compliance Directive that provided inconsistent interpretation and enforcement of the OSHA 1926.754(b)(3) standard.  The International Association regrets that OSHA, under the previous Administration issued this Compliance Directive that was contrary to the OSHA Subpart R – Steel Erection standard and has contributed to several serious incidents and fatalities.  The International Association has formally denounced this OSHA Compliance Directive because it has removed specific safety provisions that are necessary to protect our members during the steel erection process. The OSHA Subpart R – Steel Erection standard 1926.754(b)(3) requiring a decked or planked floor provides the following safety provisions to our members and others on the job site.


Maintain decked and planked floor on multi-story.

  1. Decking and planking provides protection from falling objects.
  2. Decking and planking provides a safe work platform for rescue.
  3. Decking and planking limits the fall distance.

Fall Protection Requirements for a Controlled Decking Zone

There are two primary fall protection requirements pertaining to Ironworkers installing metal decking.  The first OSHA 1926.760(c)standard states “a controlled decking zone may be established on a structure over 15 and up to 30 feet above a lower level where metal decking is initially being installed and form the leading edge of a work area.”  The second OSHA 1926.760(c)(1) states “each employee working at the leading edge in a controlled decking zone shall be protected from falls hazards of more than two stories of 30 feet, whichever is less.”  Note: there are additional OSHA requirements regarding the use of controlled decking zones that must be addressed prior to the commencement of metal decking operations.   

The “2012 Zero Fatality” campaign requires all members to “intervene and prevent unsafe conditions and unsafe acts” in the workplace.  We need your support to promote “2012 Zero Fatality” campaign by “targeting the deadly dozen hazardous activities that lead to fatalitiesand disabling injuries.

Learn more about the "Deadly Dozen" hazards on construction sites.