Suspended platform stabilization: Why it’s critical

Figure 1. A BMU suspended platform being continuously stabilized by a mullion track.

When working on permanently installed suspended platforms, platform stabilization is critical to ensure both worker safety and the longevity of the equipment. Understanding the fundamentals of platform stabilization can help prevent accidents, protect the building, protect workers, and ensure that equipment is used effectively in compliance with regulations. (See figure 1).

What Is the Purpose of Platform Stabilization?

Figure 2 shows a 3D render that is using a track system for platform stabilization.

The goal of platform stabilization is simple: to keep the platform steady against the building façade, minimizing movement and reducing the risk of accidents. Stabilization ensures that the platform remains secure and workers can perform tasks safely. Stabilization also plays a large role in angled facades where the platform would naturally gravitate away from the building envelope. Without platform stabilization, factors such as wind could easily blow the platform away from the building, causing damage to the façade, platform, and most importantly the workers.

Methods of Platform Stabilization

There are three primary methods for achieving platform stabilization:

Figure 3 shows a 3D render that is using intermittent stabilizers for platform stabilization

• Continuous Stabilization (See figure 2)
• Intermittent Stabilization (See figure 3)
• Angulated Roping

The choice between these three methods often depends on the building’s design, the site conditions and/or when the equipment is being installed (new construction vs retrofit).

Continuous Stabilization

Continuous stabilization is achieved through a mechanical connection between the platform and the façade. This provides a continuous connection as the platform moves up and down the side of a building, always ensuring stability and keeping the platform tight against the façade.

The most common method for continuous stabilization is a track system, often referred to as a “mullion track.” These tracks, which are site specific must comply to code and safety regulations. They can be installed either internally or externally on the building façade.

Figure 4. A close look of a continuous stabilizing guide attached to the platform.

Continuous stabilization is commonly installed during the buildings construction since installation is much easier during construction and may be incorporated into the design of the curtain or window wall’s mullions.

Figure 5. The continuous stabilizing guide installed into the mullion track. 

Users of continuous stabilization insert guides into the track; (See figure 4) the guides remain in the track throughout the drop, staying with the platform as it descends. (See figure 5)

Intermittent Stabilization

As opposed to continuous stabilization, intermittent stabilization requires spaced-out connections, or

“Intermittent stabilization anchors” (ISAs), permanently installed on the building façade. (See figure 6)

These connections allow the platform, when secured by a suitable lanyard between the platform’s support ropes and the building’s ISAs, to remain secure without a full-length track system. (See figure 7). One of the benefits of ISA’s is that they can be installed during the building’s construction but also installed as a retrofit on most existing buildings.

Typically, intermittent stabilization is achieved with either recessed, flush anchors or anchors, commonly referred to as buttons, that extend from the building’s facade. Anchors that extend from the façade are designed to receive a connector that is on the end of the tie-back lanyard and connects to the anchors intermittently as the platform descends. (See figures 8 & 9). Recessed anchors use a lanyard with a ball-lock pin that is inserted into the ISA and removed utilizing its activation button (See figure 10). The spacing of these anchors can vary, but must be at a maximum every 3 floors or 50 feet, whichever is less.

FIgure 6. Provides a diagram that labels different intermittent stabilization components.

Angulated Roping

Figure 7. A platform being stabilized by the adjustable cable lanyard attached to the intermittent stabilizer.

When using a stabilization system, the max distance from the top of the building to the first stabilizing point may not be more than 50 feet. When angulated roping is introduced the allowable distance increases to 75 feet.

Angulated roping is when the cables anchor point is set in further than plum keeping a minimum 10-pound force in-between the basket and the building. Angulated roping is the only adequate means from 130 feet or lower.

Regulatory Requirements

The maximum wind speed allowed for suspended scaffolds is 25 mph. The minimum ultimate design load for the components of platform stabilization systems is 600- pounds, which includes a safety factor of 4.

Figure 8. A macro photo of the intermittent stabilization button anchor with removable cable lanyard.

Unlike other suspended access equipment, there are no specific testing requirements for stabilization. It is highly recommended that the platform users report any issues.

Figure 9. Up-close photo of the typical ISA button.

Compliance with these regulations ensure that platforms remain stable under the stresses of movement, wind, and other environmental factors, safeguarding workers, building and equipment alike.

Platform stabilization is a vital aspect of permanently suspended work systems. Whether using continuous, intermittent, or angulated methods, the primary objective is to ensure worker safety and platform security. Compliance with OSHA regulations and local codes is essential for maintaining the integrity of the stabilization system. Choosing an appropriate design for the specific application is crucial in the system’s useability and safety.

By understanding these methods and their applications, construction and maintenance teams can ensure that platforms remain secure, no matter the challenges posed by the environment or building structure.

Figure 10. ISA ball lock pin with the cable lanyard retrofitted into concrete.