wall ladder metal

Product Description

. Material:

• Steel: Most common. Often heavy-duty welded assemblies.
  • Mild Steel: Strong and durable, often powder-coated for corrosion resistance.

  • Hot-Dip Galvanized Steel: Provides excellent corrosion protection, ideal for outdoor or harsh environments.

  • Stainless Steel: Used where rust is a significant factor (e.g., food processing, marine environments) due to its superior corrosion resistance.

• Aluminum: Lightweight, strong, and corrosion-resistant. Cannot be used near exposed electrical equipment.

• Fiberglass (FRP): While not metal, it's worth noting as an alternative for applications requiring electrical non-conductivity.

2. Load Capacity (Duty Rating):

• Metal ladders are typically designed to support a significant load.

• OSHA Requirement: Fixed ladders must be able to support at least two loads of 250 pounds (114 kg) each on two consecutive rungs. Each step or rung should be able to support at least 250 pounds applied in the middle.

• Common industrial ladders are rated for 350 lbs or 500 lbs capacity.

3. Dimensions and Spacing:

• Rung/Step Spacing (Rise):
  • Generally, rungs, steps, or cleats must be spaced not less than 10 inches (25 cm) and not more than 14 inches (36 cm) apart, measured centerline to centerline.
  • Some specific exceptions exist (e.g., elevator pit ladders).
• Rung/Step Width (Clear Width):
  • Fixed ladders typically require a minimum clear width of 16 inches (41 cm) between side rails.

  • Some manufacturers offer 17" or 18" wide rungs.
• Rung/Step Design:
  • Must be designed to minimize slipping. This can include corrugated, knurled, dimpled, or skid-resistant coated surfaces.

  • Minimum diameter of 3/4" for metal rungs.
• Side Members (Rails):
  • Commonly made from steel angle (e.g., 1/4"x2"x2" steel angle) or flat bar stock (e.g., 2-1/2" x 3/8" flat steel).
  • If constructed of multiple parts, the assembly must be as strong as a one-piece rail.
• Wall Clearance (Back Side Clearance):
  • Minimum perpendicular distance from the centerline of the rungs to any obstruction behind the ladder (the wall) must be at least 7 inches (18 cm).

  • For elevator pit ladders, it can be 4.5 inches (11 cm).
• Climbing Side Clearance:
  • Minimum perpendicular clearance between the centerline of the steps or rungs and any obstruction on the climbing side of the ladder must be 30 inches (76 cm).
  • Fixed ladders without cages or wells must have at least a 15-inch (38 cm) clear width to the nearest permanent object on each side of the ladder's centerline.
• Stand-off Brackets:
  • Used to mount the ladder to the wall, typically providing the 7-inch wall clearance.
  • Usually bolted on.

4. Safety Features and Requirements (especially for ladders exceeding certain heights):

• Fall Protection:
  • For fixed ladders extending 24 feet (7.3 m) or more above a lower level, a personal fall arrest system or a ladder safety system is required.

  • Cages are no longer considered compliant fall protection for newly installed or replacement fixed ladders over 24 feet as of November 19, 2018. Existing caged ladders installed before this date may still be compliant, but the trend is towards ladder safety systems or personal fall arrest systems.

• Ladder Safety Systems: Consist of rails or cables running vertically along the ladder, connected to a climber's harness.

• Personal Fall Arrest Systems (PFAS): Include a harness, lanyard, and suitable anchor point.

• Landing Platforms:
  • If the total length of the climb exceeds 50 feet (15.2 m) (for caged ladders) or 150 feet (45.7 m) (for ladders with self-retracting lifelines), landing platforms are required at intervals.
  • Landing platforms should be provided at maximum intervals of 50 feet (15.2 m) for ladder sections.

• Handrails (Walk-Through):
  • For through or side-step fixed ladders, side rails must extend 42 inches (1.1 m) above the top access level or landing platform.

  • Walk-through handrails are often available, extending above the landing surface for safe transition.

• Safety Cages (for existing installations or specific uses):
  • If present, cages typically begin 7 feet from the bottom of the ladder.
  • Horizontal bands spaced not more than 4 feet apart.

  • Vertical bars spaced not more than 9.5 inches apart, on the inside of horizontal bands.
  • Cages must be free of projections and designed for easy entry/exit.
• Pitch: Fixed ladders should have a pitch between 75 degrees and 90 degrees from the horizontal (vertical).

5. Finish:

• Powder Coating: Common for steel ladders, providing durability and corrosion resistance. Available in various colors (e.g., safety yellow, gray).
• Hot-Dip Galvanized: For superior corrosion protection.
• Anodized: For aluminum ladders, enhances corrosion resistance and appearance.

Relevant Standards and Regulations:

• OSHA 1910.23 (Ladders): General requirements for all ladders.
• OSHA 1910.28 (Duty to have Fall Protection and Falling Object Protection): When fall protection is required.
• OSHA 1910.29 (Fall Protection Systems and Falling Object ProtectionïCriteria and Practices): Design criteria for fall protection systems.
• ANSI A14.3 (American National Standard for Ladders-Fixed-Safety Requirements): Provides detailed safety requirements for fixed ladders