The installation of rebar on a multilevel residential tower involves several potential hazards that need to be addressed to ensure worker safety. Here's a risk assessment:

Hazards:

• Falls from Heights: This is a primary concern when working on multi-level structures. Workers can fall from unprotected edges, openings, or while moving between different levels 1, 2, 3, 7.
• Falling Objects: Tools, equipment, or rebar itself can fall and strike workers below [1].
• Structural Instability: Improperly secured rebar or overloading a structure can lead to collapses 6, 12.
• Musculoskeletal Injuries: Lifting, carrying, and placing rebar can cause strains, sprains, and other musculoskeletal disorders.
• Impalement Hazards: Protruding rebar can pose a significant impalement risk if workers fall onto it [2].
• Weather Conditions: Wind, rain, or ice can create slippery surfaces and increase the risk of falls or material handling accidents.
• Equipment Hazards: Cranes and other lifting equipment can cause struck-by or caught-between injuries if not operated safely.

Risk Assessment:

• Likelihood: The likelihood of these hazards occurring can vary from possible to likely, depending on the specific task, site conditions, and safety measures in place.
• Severity: The severity of potential injuries ranges from minor cuts and bruises to serious injuries, permanent disabilities, or fatalities.

Control Measures:

1. Fall Protection:
   • Guardrail Systems: Install guardrails along unprotected edges and openings 1, 2, 3, 7, 9, 11.
   • Safety Net Systems: Use safety nets to catch workers in case of a fall 1, 2, 3, 7, 9.
   • Personal Fall Arrest Systems (PFAS): Provide and require the use of PFAS, including harnesses, lanyards, and anchor points 1, 2, 3, 7, 9.
   • Ensure proper training on the use and inspection of fall protection equipment.
2. Falling Object Protection:
   • Securing Loose Items: Secure all tools, equipment, and materials to prevent them from falling [1].
   • Overhead Protection: Provide overhead protection for workers below where rebar is being installed [1].
   • Toe Boards: Install toe boards on elevated platforms to prevent tools and materials from falling 7, 9, 11.
   • Establish a drop zone and implement a "no entry" policy during lifting operations.
3. Structural Stability:
   • Bracing and Shoring: Use appropriate bracing and shoring to support walls and columns [3].
   • Engineer Approval: Obtain written approval from a structural engineer for any modifications that affect the strength of the structure [4].
   • Load Limits: Ensure that construction loads do not exceed the structure's capacity [2].
4. Ergonomics:
   • Proper Lifting Techniques: Train workers on proper lifting techniques to minimize strain.
   • Mechanical Aids: Use mechanical aids such as cranes, hoists, and dollies to move heavy rebar bundles.
   • Work/Rest Schedules: Implement work/rest schedules to reduce fatigue.
5. Impalement Protection:
   • Rebar Caps: Use rebar caps or bending the rebar over to eliminate impalement hazards [2].
6. Weather Conditions:
   • Monitor Weather: Monitor weather conditions and postpone work during high winds, heavy rain, or icy conditions.
   • Slip-Resistant Surfaces: Use slip-resistant surfaces and footwear.
7. Equipment Safety:
   • Qualified Operators: Ensure that all equipment operators are properly trained and certified.
   • Regular Inspections: Conduct regular inspections of cranes and other lifting equipment.
   • Load Charts: Adhere to load charts and safe lifting practices.
8. Controlled Decking Zone (CDZ):
   • Establish a CDZ where metal decking is initially being installed 2, 8, 10.
   • Limit access to the CDZ to only those employees engaged in leading edge work 8, 10.
   • Clearly mark the boundaries of the CDZ with control lines 8, 10, 17.
   • Ensure that employees working in the CDZ have completed CDZ training 2, 8, 10, 17.

Monitoring and Review:

• Regularly inspect the work area and equipment to identify and correct hazards.
• Conduct safety meetings to discuss potential hazards and safe work practices.
• Review and update the risk assessment as needed to reflect changes in site conditions or work processes.
• Investigate all incidents and near misses to prevent recurrence.

Specific Recommendations:

• Develop a site-specific erection plan that addresses the unique challenges of the project 1, 19.
• Ensure that all workers are properly trained and competent to perform their assigned tasks 2, 8, 10, 17.
• Enforce strict adherence to all safety regulations and procedures.
• Provide clear communication and coordination between all trades working on the project.
• Establish emergency procedures and ensure that all workers know what to do in case of an accident.