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Ladders and Stairs

This program area contains information and guidance for the safety of all BNL staff, contractors, visitors, and guest on-site and off-site for the proper design and use of ladders and stairs with associated inspection requirements.

Ladder and stair requirements at BNL fall into the following SBMS Subject Area: Ladders and Stairs, Design, Inspection and Use.

OSHA Ladder Types

Ladders can be fixed (vertical), or portable. Portable are classified as strait (extension) ladders or self-supporting (such as A-Frame) ladders. Ladders must be designed, built, maintained and used in accordance with the OSHA General Industry standard (29CFR1910) and applicable ANSI standards.

OSHA Portable Ladder Types

OSHA (29CFR1910.25) rates portable ladders for different duty (see table below).

Ladder Type Duty Rating Description
Type 1AA 375 lb. Extra-heavy-duty industrial ladder
Type 1A 300 lb. Heavy-duty industrial ladder
Type 1 250 lb. Heavy-duty industrial ladder
Type 2 225 lb. Medium-duty commercial ladder
Type 3 200 lb. Light-duty household ladder (should not be used at laboratory)

Ladder Compliance Program

All ladders used at Brookhaven National Laboratory must meet OSHA requirements and/or industry standards. The OSHA Guide for ladders is provided below. A number of fixed ladders (typically vertical mounted) were installed prior to OSHA requirements being imposed on this facility. To determine the compliance status of fixed ladders, an Extent of Condition (EOC) was initiated by the Assistant Lab Director for Environment, Safety & Health and is provided below. In order to ensure worker safety, ladders need to be inspected before use and the Laboratory has a program to inspect fix ladders for compliance. These inspections are performed by trained staff (TQ-LADDER-INSPECT). Copies of the compliance and inspection training and approved checklist are provided below.

The Office of the Laboratory’s Chief Engineer maintains the inspection results for fixed ladders (Fix Ladder Inspection Program Result). The results were used to determine additional controls needed to use ladders that non-conformances to laboratory requirements. These controls are used by climbers to allow safe use of these ladders. Examples of how users are made aware of the additional controls are: Ladder Briefing Sheets (managed by F&O) and Ladder Information Cards (managed by the Department/Division).

Fixed Ladder Program at BNL

Requirements for the safe use of fixed vertical ladders at the laboratory (which is part of the on-line training) are described in a video that is posted on the Safety and Health Services Website and can be found here.


Stairs need to be designed and installed to meet the most stringent requirements from the Occupational Safety & Health Administrations (OSHA) General Industry standard (29CFR1910), New York State Unified Code (Building and Fire Safety), and the National Fire Protection Association (NFPA 101). Stairs are classified based on occupancy requirements as egress or industrial. Fire Protection Engineering is required to assign classification.

Egress Stairs

Egress Stairs must meet the requirements of New York State Building Code (Chapter 10) and NFPA 101, Life Safety Code (Chapter 7). Examples of egress stair design requirements are provided below.

Industrial Stairs

Industrial Stairs are designed to meet the requirements of OSHA (specifically sections 1910.23 & 1910.24) and NFPA 101, Life Safety Code (Chapter 40). Examples of industrial stair design requirements are provided below.

Alternate Stairs

In some limited space applications, alternate stair designs can be considered. These stairs typically fall under two (2) categories, Ship’s Stairs or Alternating Tread Devices. OSHA, through the Standard Interpretation process, allows these devices under the OSHA Proposed rules (05/20/2003) that addresses recommended changes in Walking and Working Surfaces; Personal Protective Equipment (Fall Protection Systems). The proposed rule can be found here.

Ship's stairs (sometimes referred to as ship’s ladders) and Alternate Tread Devices are stairways equipped with treads and stair rails with a slope greater than 50° to 70° from the horizontal. Alternating tread devices are typically vendor designed, pre-engineered systems (Off the self) and need to be evaluated independently prior to purchase.

Ship’s ladder need to meet the following design requirements:
  • Stairs with four or more risers shall be provided with at least one handrail. A stair rail system shall be provided on all unprotected sides or edges of stairways with a fall hazard of four feet or more.
  • Handrails and stair rails shall meet the applicable requirements below. Stair rail systems may also serve as handrails when properly installed. The sides and edges of stair landings with a fall hazard of four feet (1.2 m) or more, unless otherwise enclosed, shall be provided with guardrail systems.
  • Stairs shall be capable of supporting, without failure, at least five times their maximum intended load. Stairs shall have a minimum vertical clearance of seven feet.
  • Stairs shall be installed with uniform riser heights and tread depths between landings.
  • Ship's stairs shall be installed at a slope between 50 degrees and 70 degrees from the horizontal.
  • Risers shall be open; treads shall be at least four inches (10 cm) in depth, 18 inches (46 cm) in width, and have a vertical rise between tread surfaces of six and one-half to 12 inches (16 to 30 cm).
  • Handrails meeting the requirements of § 1910.28 shall be installed on both sides of ship's stairs.
Handrail and stair rail systems
  • Handrails and the top rails of stair rail systems shall be capable of withstanding, without permanent deformation or a loss of support, a force in any downward or outward direction at any point along the top edge, of at least 200 pounds applied within two inches of the top edge of the rail.
  • Height criteria (measured from the top of the surface of the tread in line with the face of the riser at the forward edge of the tread on existing system):
    • The height of handrails shall not be less than 30 inches nor more than 42 inches on existing systems.
    • The height of handrails installed on or after shall not be more than 37 inches nor less than 30 inches on newly installed systems.
    • The height of stair rail systems shall not be less than 30 inches from the upper surface of the tread.
    • The height of stair rail systems installed on or after shall be not less than 36 inches.
    • A stair rail may also serve as a handrail when the height of the top edge is not more than 42 inches nor less than 36 inches.
    • A stair rail may also serve as a handrail when the height of the top edge is not more than 37 inches nor less than 36 inches (note: users must not be exposed to a fall potential greater than 4 feet surface.
  • The minimum clearance between handrails, including the top edge of stair rail systems serving as handrails, and any obstructions shall be one and one-half (1½) inches.
  • Handrail and stair rail systems shall be surfaced to prevent injury to employees from punctures or lacerations, and to prevent snagging of clothing.
  • Openings in a stair rail system shall be a maximum of 19 inches in their least dimension.
  • Handrails shall have the shape and dimension necessary to provide a firm handhold for employees.
  • Ends of stair rail systems and handrails shall not present a projection hazard.

Examples of the ships stair design requirements are provided below.

The National Fire Academy has provided a short training summary for egress handrail requirements. See Means of Egress: Handrail for additional information.