ASME A17.3-2023 Guide: On-Site Retrofit Rules for Existing Elevators and Escalators

What is ASME A17.3 and Why Do You Need It On Site?

If you manage, maintain, or upgrade buildings with existing elevators or escalators, ASME A17.3 is your critical rulebook for safety retrofits. Unlike the A17.1/CSA B44 code, which governs new installations, A17.3 focuses exclusively on bringing older equipment up to modern safety benchmarks. Think of it not as a design standard for new construction, but as an enforceable set of retrofit requirements triggered by specific conditions like modernization projects, major repairs, or following an incident investigation.

On site, you encounter A17.3 when a building owner plans an elevator modernization, when an authority having jurisdiction (AHJ) mandates safety upgrades after an inspection, or when performing a major component replacement that alters the system’s safety characteristics. It provides the actionable checklist for what must be added or modified on the existing equipment to mitigate known hazards that weren’t addressed by the original installation code.

Core On-Site Problems Solved by A17.3 Compliance

The standard directly addresses critical safety gaps in legacy elevator and escalator systems. Common on-site problems it solves include:
* Unprotected Hoistway Openings: Preventing falls into the shaft during maintenance or from adjacent floors.
* Inadequate Firefighter Service: Ensuring emergency recall functions work reliably for first responders.
* Unsafe Pit Conditions: Eliminating hazards like unguarded sheaves and inadequate stop switches where technicians work.
* Escalator Entrapment Risks: Mitigating points where clothing or body parts can be caught, a leading cause of escalator injuries.
* Uncontrolled Car Movement: Addressing risks from single-component failures that could allow unintended motion with doors open.

Non-compliance during a retrofit project can lead to failed inspections, project delays, rejection of permit applications, and most critically, the persistence of life-safety hazards that expose building owners and service providers to significant liability.

Key Technical & Safety Requirements for Field Application

A17.3 translates broad safety principles into specific, actionable tasks. Its requirements are often more performance-based than prescriptive, focusing on the hazard to be mitigated. Key operational highlights include:

1. Hoistway Access and Protection:
* On-Site Rule: Any hoistway opening (for landing doors, ventilation, etc.) must be constructed or retrofitted to resist accidental impact and unauthorized entry. This often means adding or reinforcing kick plates and ensuring door locking mechanisms are robust.
* Field Verification: Inspectors will check that landing sills are solid and that any openings greater than 2 inches in any dimension are addressed. Verify that door lock monitoring is functional per modern requirements.

2. Pit Safety Retrofit:
* On-Site Rule: The elevator pit must have a permanent stop switch within easy reach of a technician working in the pit. Previously unguarded moving components (like sheaves) adjacent to the pit ladder or walk space must be guarded.
* Field Verification: Confirm the stop switch is “red and mushroom-headed,” is hardwired to remove power from the drive motor, and is accessible from all pit working areas. Visually inspect for adequate guarding.

3. Unintended Car Movement (UCM) Protection:
* On-Site Rule: This is a critical retrofit. Systems must be upgraded to prevent the elevator car from moving with the doors unlocked or open. This typically involves adding a dedicated UCM device or validating that the existing brake and control system can perform this function under failure conditions.
* Field Verification: This is a functional test. Technicians must simulate a brake failure or control system fault with the car at a landing and doors open. The system must prevent any movement exceeding a very small threshold (e.g., 4 inches). Documentation of this test is mandatory for AHJ review.

4. Escalator Step/Skirt Performance and Entrapment Mitigation:
* On-Site Rule: Retrofits must address the clearance between the moving step and the stationary skirt panel. This often requires installing performance-based step/skirt intrusion detection devices (like proximity sensors or brush strips) or replacing skirt panels to achieve a compliant, minimal gap.
* Field Verification: Use feeler gauges to measure step-to-skirt clearances at multiple points. For intrusion devices, conduct a functional test by simulating an obstruction (using a standardized test probe) to ensure the escalator stops immediately.

Regulatory Context and On-Site Compliance Workflow

ASME A17.3 is adopted into law by states, provinces, and local municipalities across North America. Its application is not optional when invoked by the local AHJ (typically a city or state elevator inspector).

On-Site Compliance Workflow:
1. Triggering Event: A modernization project plan is submitted, or an AHJ inspection cites a hazard that requires an A17.3 retrofit.
2. Gap Analysis: The qualified elevator contractor surveys the existing equipment against the current A17.3 requirements to create a retrofit scope of work.
3. Permit Submission: Construction permits for the elevator work must include the A17.3 compliance plan. The AHJ reviews this plan before granting approval to proceed.
4. On-Site Implementation: Work is performed according to the plan. Key retrofits (like UCM tests) require witness points for the inspector.
5. Final Inspection & Documentation: The AHJ performs a final inspection, verifying all retrofits. The contractor provides a data package confirming compliance, which becomes part of the building’s permanent elevator records.

Differentiation from Other Codes: While local building codes may reference elevator safety, A17.3 is the specific, technical standard inspectors use for evaluation. Do not assume compliance with an older version of A17.1 satisfies A17.3 requirements; the retrofit code has unique mandates.

Target Professionals and Risks of Non-Compliance

Who Uses This On Site:
* Elevator Modernization Project Managers: To define the scope and ensure the contract meets all mandated safety upgrades.
* Elevator Technicians & Supervisors: To perform the correct physical retrofits and execute required tests.
* Building Owners & Facility Managers: To understand their liability and the mandatory scope of a modernization project.
* Third-Party Inspectors & AHJs: As the definitive checklist for approving retrofit work.

On-Site Risks of Ignoring A17.3:
* Project Shutdown: The AHJ will halt work if non-compliant retrofits are discovered, leading to costly delays.
* Failed Final Inspection: The elevator will not receive an operating permit, rendering it unusable.
* Catastrophic Liability: If an accident occurs involving a hazard that A17.3 was designed to prevent, negligence is easily established, leading to severe legal and financial consequences.
* Increased Insurance Premiums or Denied Coverage: Insurers may require compliance with the latest safety codes.

Real-World On-Site Scenario

A 1990s office building is modernizing its three elevators. The contractor’s proposal includes new controllers, doors, and fixtures. The building department’s permit review stamps the plans with the note: “Comply with ASME A17.3-2023.” The project manager must now ensure the scope includes:
1. Upgrading pit stop switches to the required type and location.
2. Installing an Unintended Car Movement (UCM) protection device on each elevator.
3. Verifying and correcting hoistway door locking and reinforcement.
4. Scheduling the functional UCM test with the city inspector for witness.

Without these items, the project passes neither inspection nor the final acceptance test, delaying tenant move-ins and creating contract disputes.

Common On-Site Misconceptions

* Misconception 1: “Our modernization is just a controller swap, so A17.3 doesn’t apply.”
* Reality: Any permit for work on an existing elevator can trigger an AHJ review under A17.3. A controller change is often the logical time to add required safety retrofits like UCM protection.
* Misconception 2: “The equipment was originally built to A17.1, so it’s grandfathered and safe.”
Reality: “Grandfathering” applies to routine maintenance, not safety-driven retrofits. Once a retrofit is undertaken or mandated, the applicable standard is the current* A17.3, not the original installation code. Its purpose is to eliminate known hazards that older codes did not address.

Always confirm the specific edition of A17.3 adopted by your local jurisdiction before planning retrofit work, as requirements evolve to address new safety learnings.