As mast climbing scaffolds become more and more prevalent in North America’s construction industry, more attention needs to be paid to the new technology’s proper use, its supervision and safety training – or retraining – for scaffold workers, according to the LHSFNA’s Senior Safety and Health Specialist Travis Parsons.

“It is no surprise that these scaffolds are enjoying wider use,” says Parsons. “They are proven to increase production while alleviating many safety issues, particularly those pertaining to ergonomic injuries.” Mast climbers are relatively easy to move and erect and they allow safe work at higher levels than traditional scaffolds. They are used in brick and masonry work, glazing, restoration projects and many other similar activities. Mast climbers are becoming the scaffolds of choice in the construction industry.

Although there are many benefits to the use of this equipment, it is important to note that it is not fool-proof. The significant number of fatalities (see sidebar for a partial list) indicates that safety supervision and training in the U.S. has fallen a step behind the new technology.

With proper workforce training, mast climbing scaffolds are safer than other options, but they still have significant pitfalls. Common hazards include:

Erection flaws

  • Configuring a platform in a manner that deviates from the original design.
  • Lack of a control switch when heavy materials are lifted.
  • Lack of lateral anchorage at regular intervals to provide stability.
  • Anchoring the mast at locations not capable of supporting the lateral loads.
  • Lack of top mast to prevent further upward movement.
  • Due to a lack of barriers, the dropping of tools and materials from the platform when it moves up or down.
  • Lack of proper connections between the structural members of the platform.
  • Use of corrosive and damaged platform structural members.
  • Excessive gaps between the platform and the edge of the building.
  • Lack of proper fall protection when the platform is too far away from the face of the building.
  • Placing the platform too close to live electrical lines.


  • Overloading the platform and the unavailability of the load table at the site.
  • Platform descending out of control or collapsing to the ground.
  • During dismantling, removing the last tie without providing additional stability to the mast.

Inadequate training, supervision

  • Lagging safety training
  • ack of competent and qualified persons on the job.

Fatal Incidents Raise Concern

  1. pril 3, 2006, Boston, MA: a 20,000-pound construction platform collapsed and then crashed 13 stories onto a busy downtown street, killing three people and crushing cars in traffic lanes.
  2. March 4, 1995, Miami, FL: three workers were killed and two injured when a mast climbing platform failed 75 feet in the air.
  3. June 27, 2003, Philadelphia, PA: a worker was killed when he fell 85 feet from a mast climbing scaffold.
  4. September 9, 2003, Camden, NJ: while being dismantled, a 120-foot mast climbing scaffold became unstable and killed another worker.
  5. November 18, 1998, Pensacola, FL: a worker was killed and another was injured when a mast climbing scaffold dropped 60 ft to the ground.
  6. October 6, 1992, Alma, MI: two workers were killed when they fell 46 feet due to overloading a plywood span between the mast climber and the wall.
  7. September 24, 2003, Brick, NJ: a worker fell 40 feet due to lack of a barrier on a mast climbing scaffold.

“The sad thing,” says Parsons, “is that these mast climber fatalities could have been prevented had the appropriate safety precautions been taken. Workers must be better trained. In many cases, workers who are accustomed to using to older scaffold types – that is, tube and coupler or suspended scaffolds – are assigned to mast climbers for the first time, without adequate knowledge and training.”

Such assignments are direct violations of OSHA regulation CFR 1926.454(c): “When the employer has a reason to believe that an employee lacks the skill or understanding needed for safe work involving the erection, use or dismantling of scaffolds, the employer shall retrain each such employee so that the requisite proficiency is regained to that specific scaffolding.”

The Laborers-AGC Education and Training Fund has long conducted instructor training in all aspects of scaffold use. In recent years, increased emphasis has been placed on mast climbing scaffolds, and “Powered Mast Climbing Scaffolds” is an important module in the Fund’s new scaffold training program. In addition, the Laborers-AGC established a relationship with Hydro Mobile, Inc. – a major North American manufacturer, based in Canada – so that Laborers’ training funds can purchase mast climbers at a discounted group rate for use in local training programs. Several funds throughout the Laborers’ training network have taken advantage of this opportunity.

“There needs to be a conscious effort to retrain workers on the hazards and proper usage of mast climbing scaffolding,” says Parsons. “There also needs to be adequate competent persons, who are qualified to work with this type of scaffolding, on every construction worksite. With the appropriate safety considerations, this equipment can be beneficial to the employer and employee.”

For further information and safe practices for mast climbing scaffolding, contact a local Laborers’ training fund or see the following:

America National Standards Institute (ANSI) (ANSI/SIA A92.9-1993)

Occupational Safety and Health Administration (OSHA) (Subpart L-Scaffolds)