Solution Summary: Remote-Controlled Chute for Concrete Mixer
A remote-controlled (RC) chute for a concrete mixer is an engineering control that can help reduce work zone struck-by injuries, skin contact with portland cement, and musculoskeletal injuries. The remote can control the placement of the telescoping chute and the flow of concrete without manually adjusting the chute or moving the truck during pouring operations.
A RC chute, such as the EZEXTENZ, can be installed on most standard concrete mix trucks as specified by the manufacturer Månsarps Svets & Maskin (MSM). This hydraulic, 30-feet chute has a swing radius of 180 degrees and also the ability to vary flow of concrete and drum speed.
The overall weight of the chute system is 1,550 pounds and the hydraulic pump capacity can range between 9 to 12 gallons per minute.
A one-week installation of the chute on all standard models of rear discharge ready mix trucks is included at the EZEXTENZ facility in Tuscaloosa, Alabama.
In general, working in road construction sites has an increased risk of work zone struck-by injuries and fatalities. Based on preliminary CFOI data, there were 116 work-related fatalities at road construction sites in the U.S. in 2014. The Construction Chart Book 5th edition published by CPWR, Chapter 46 shows vehicles were the source of more than half of the fatalities at road construction sites - double the proportion of such deaths in the overall construction industry from 2008 - 2010 (graph 46b). Among fatalities involving vehicles and heavy equipment at road construction sites, most were workers on foot or non-passengers who were struck by vehicles or heavy equipment in the work zone or passing vehicles that entered the work zone.
Workers who are exposed to Portland cement and products containing Portland cement can get occupational skin diseases. Due to the cement's abrasive, alkalinic, and hygroscopic (drawing moisture from the skin) properties, the occupational skin diseases may include irritant contact dermatitis, allergic contact dermatitis (from sensitizers such as hexavalent chromium) and caustic burns.
Workers that are repetitively lifting heavy chutes on a frequent basis are also at risk of musculoskeletal injuries.
How Risks are Reduced:
Using a RC chute minimizes the need to drive and move concrete mix trucks during pouring operations. As a result, mix trucks remain stationary reducing the risk of striking workers during vehicle back-ups.
Additionally, operators can control the chute via a radio frequency remote control without needing to manually lift the heavy chute or be exposed to the harmful chemical effects of concrete that can cause occupational skin disease.
There have not been independent published studies measuring the effect of using remote controlled extension chutes on reducing musculoskeletal injuries. Regardless, safety and health experts believe that chute operators will be less likely to develop musculoskeletal injuries when all the chute lifting is performed by a machine. In addition, with the longer reach and more exact placement of the concrete with the EZEXTENZ, manually moving heavy concrete through raking or by pushing wheel barrows is reduced.
There have not been independent published studies measuring the effect of using RC chute on reducing occupational skin disease. Nonetheless, safety and health experts anecdotally believe that by remotely operating the extension chutes, chute operators will not come in direct contact with concrete because they do not need to manually handle and adjust chutes thus eliminating the risk of contact with cement.
Effects on Productivity:
As claimed by the manufacturer, "the highly efficient chute technology significantly reduces the hard labor required of the operator, expanding the possible pool of qualified drivers. It decreases the number of workers needed at the construction site and in some cases can also replace the need for a costly pump truck. This improves the cycle time resulting in a more productive operation."
For maintenance, the manufacturer recommends to wash the chute for a few minutes after each load, apply form oil 2-5 times a day, and power wash at the end of the day. In addition, they also suggest to grease the chute once per month and change the oil once per year.