CDM Systems, Inc. > Resources > Technical Documents > White Paper: Put Safety First with En-Masse

Put Safety First with En-Masse

Employing this conveyor design throughout an operation achieves the added benefit of increased productivity.

By Andrew Parker, President, CDM Systems, Inc.


According to data from the World Monetary Fund, the annual cost to U.S. businesses due to lost time from workplace injuries exceeds the gross domestic product (GDP) of 91 countries worldwide1. Injuries and illness caused by working conditions or equipment operation cost U.S. employers nearly $62 billion in 20132.

Given the efforts of modern-day regulators and the emphasis companies put on compliance with local and federal safety measures, it’s hard to believe that injuries to employees still manage to cost as much as $1 billion per week in the U.S.3 While the financial impact of workplace safety is impossible to ignore, it hardly represents the additional impact safety has on a company’s bottom line.

A lack of concern for safety can become a considerable drain on an operation’s profits. Employers pay the majority of medical fees related to a workplace injury, as well as a percentage of an injured employee’s compensation. In addition to these direct costs, workplace injuries also cause an indirect negative impact on companies. From hiring temporary employees, lost productivity, and quality disruptions to the potential damage to employee morale, a focus on safety is something that can improve a company’s overall financial health.

The growing global demand for products, in addition to the increasing demand for additional profits, continues to put pressure on industrial and manufacturing operations to elevate output. That pressure can compromise workplace safety. From 2010 to 2014, material handling incidents caused 37% of injuries in manufacturing, and those injuries accounted for 32% of total workers’ compensation claims4.

Regardless of the financial burdens that result from diminished workplace safety, companies still feel the pressure to enhance efficiency and daily productivity levels. Elevating production requires a solution that balances the integration of new equipment and innovations with worker safety.

The Challenge

Another reality is that we live in a litigious society, and insurance for industrial manufacturing operators is costly. With millions of dollars and people’s lives at stake, ensuring the safest possible environment for employees is critical to attain and maintain profitability.

The first challenge when considering safety and material handling equipment, such as conveyors, is to recognize that any equipment is only capable of performing the task it is designed to accomplish. Whether they are underground at a coal mine or on the floor of a manufacturing plant, conveyors are vital to automating an operation. But they still require human interaction in order to operate effectively, so there will always be safety concerns whenever human contact is required with equipment.

Operational Safety

A conveyor’s level of safety begins with how it is designed. Covering moving parts and preventing access to materials that often move at high speeds is a starting point. The more you can minimize human contact with a conveyor, the better the chance the operation will be safe. Exposed rotating parts, like a shaft or motor, present a safety concern. Imagine a boot lace getting caught up in a shaft rotating at 2,000 rpm.

Belt conveyors are some of the most prevalent conveyors in use today, but they are inherently less safe because of the increased exposure to moving parts and the extensive number of maintenance points along a run. Belt conveyors have exposed wheels located approximately every four feet to support the belt, which means there is a potential maintenance point every four feet as well.

With a belt conveyor, there are real safety issues regarding pinch points and exposed moving parts, as well as spillage or dusting from the movement of the exposed materials. If materials become wedged under a roller or between two points on a belt conveyor, the belt can be cut, creating an unsafe operating situation. In addition, material jams can generate friction and heat that can ignite flammable materials.

Dangerous Materials

As long as dangerous materials are being moved at a manufacturing plant or industrial operation, there will be risks associated with exposing employees to those materials. Abrasive, caustic, or high-temperature materials are all hazardous to human contact when conveying. According to the Occupational Safety & Health Administration (OSHA), touch-temp regulations for surfaces are a maximum 140°F. The ash coming out of an economizer at a power plant can be 750°F, so there’s quite a disparity.

En-Masse Conveyors Can Safely Move:

  • Abrasive Materials
  • Caustic Materials
  • High-Temperature Materials

In the glass industry, mix-batch materials can come into contact with perspiring skin, adhere to it and cause a chemical burn. When cement is exiting a kiln, breathing it without a mask can result in a bloody nose from the abrasiveness and temperature of the material. Airborne material or dust can also be a significant danger, often causing much worse than a bloody nose. Grains such as corn or wheat, and products such as flour, create highly flammable, highly explosive dust. Wood pellets and sawdust are highly explosive, as is sulphur. Needless to say, controlling dust is critical to ensuring a safe working environment.

Glass, cement, fertilizers, and silica, just like fine sand, can cause significant respiratory issues if inhaled. The movement of raw sludge or manure for treatment or incineration carries E. coli bacteria, so minimizing any potential contact with these materials is imperative to protecting employee health.

Even the processing of safe materials can cause hazardous conditions. Any material that becomes airborne can settle on any surface throughout a facility, increasing the risk of slipping, maintenance issues, and the chance of fires.

Maintenance Safety

All conveyors require a certain degree of expected maintenance. Protecting maintenance workers is especially important, and following existing OSHA guidelines is required. Whether it’s a 70-pound weight limit for removable pieces, requiring a tool to gain access to moving parts, or eliminating any gap larger than a half-inch between exposed shafts and rotating equipment, OSHA guidelines are not always enough when the human factor is taken into consideration.

There is an assumption that maintenance workers will follow safety guidelines when servicing equipment. Any conveyor can be shipped and assembled with guarding in place, but maintenance workers, possibly in an effort to work faster or more efficiently, often take shortcuts that leave guards loose or completely removed. On a belt conveyor, that safety risk exists every four feet for the entire run.

The Solution

The key to maximizing safety while enhancing efficiency, productivity, and profitability lies in the adoption of an en-masse conveyor, screw conveyor or bucket elevator from CDM Systems. Sometimes the nature of a product makes it dangerous to handle. Minimizing that danger with enclosed conveyor designs is one way to create a safer operation.

The enclosed or sealed design of CDM’s en-masse conveyors, screw conveyors or bucket elevators addresses the overall safer movement of materials. It also directly addresses the human element by allowing only two access points to moving parts, as well as providing relief for maintenance workers handling heavy guards and access panels.

Conveyor Safety Highlights


  • Fully enclosed design
  • Just two maintenance locations at head and tail of conveyor run
  • No other access required for maintenance or normal operation


  • Only two penetration points with access to the rotating shaft
  • Same sealed benefits as the en-masse conveyor


  • Specialized for vertical conveying
  • Same sealed benefits as the en-masse conveyor
  • Just two maintenance locations at head and tail of run

By utilizing a sealed design, the CDM en-masse conveyor eliminates dusting and airborne material concerns. By limiting access points at the front and back of the conveyor run, the en-masse conveyor design minimizes the human factor’s impact on safety while providing easier maintenance, and can be equipped with lighter aluminum covers.

All CDM conveyors are OSHA compliant and follow Conveyor Equipment Manufacturers Association (CEMA) guidelines. CDM en-masse conveyors are the most efficient form of material handling for high-volume conveying. They are used in a wide range of applications and can handle materials ranging from ash to zinc, with inlet temperatures up to 1000°F. For conveyors that move high-temperature materials, CDM can insulate the trough or use cladding on the outside. CDM also offers new innovations in high-temperature, ceramic-based coatings that reduce touch temperatures. These paint-on coatings further enhance safety by preventing burns, while also eliminating the need for maintenance on insulating materials.

Compared to other conveyor technologies, en-masse conveyors can carry more material in less space, with less material degradation. Because it moves material in an enclosed steel casing, the en-masse design is a viable option that results in fewer injuries, less dust, fewer aspiration problems, and less potential contamination of the material.

Improve Safety With En-Masse Conveying

  • Fewer Injuries
  • Less Dust
  • Less Aspiration
  • Less Material Contamination

Every industry has unique requirements, so each en-masse conveyor system CDM creates is custom engineered to meet the specific needs of that application. The result is a system that moves large volumes of material smoothly, gently, reliably, and effectively from horizontal through vertical – all with a low cost of ownership over time. This solution becomes even more beneficial to the bottom line when you factor in the reduced number of workplace injuries and workers’ compensation claims associated with manually moving material.

CDM engineering and design principles are founded in the science of material movement, incorporating bulk density, all product characteristics, optimum chain speed intersecting with acceptable chain pull, and the innovation of wear resistance and anticorrosion techniques. CDM partners with companies to design the correct conveyor to meet the demands of any operation.


With any conveyor system, it is important to identify safety challenges before they result in an injury, worker’s compensation claim, or worse. Doing so requires a thorough understanding of a variety of material handling demands, and CDM has more than 40 years of application experience.

During that time, our experts have created solutions for several different bulk powders and solids. Our engineered processes allow you to receive, transfer, feed and convey multiple ingredients without degrading the quality of your materials. Whether you use batch, intermittent or continuous flow, CDM will specify and size the right equipment to maintain your product specifications, reduce waste, increase safety, and improve your bottom line.

CDM delivers the best solutions to bulk material handling challenges, offering unmatched durability, value, and safety for even the most demanding material transfer applications.

About The Author:

Andrew Parker is President for CDM Systems, Inc. He has more than 20 years of experience in the bulk material handling industry and oversees operations including conveyor design and development.


  1. U.S. Companies Pay For Workplace Injuries;
  2. 2013 statistical data, 2016 Liberty Mutual Workplace Safety Index;
  3. (See (2);
  4. Material handling injury data; Travelers Insurance Injury Impact Report