Industrial Facility Safety from the Loading Dock to the Plant Interior

Loading docks are one of the most critical and dangerous links in any supply chain.

• By Walt Swietlik
• Feb 01, 2022

Warehouses, distribution centers and manufacturing facilities are inherently dangerous places. Almost all essential industrial operations carry some form of risk, whether they occur at a loading dock, the plant’s interior or anywhere in between. Protecting workers, and the goods and equipment that are part of these processes, is one of the most fundamental aspects of any facility manager’s job.

The cost of accidents is high, in every respect. Plants with bad safety records can have trouble attracting employees and often suffer low employee morale, an intangible that is widely understood to hinder productivity. The tangible cost of accidents is even more daunting. Between workers’ compensation, damaged product, fulfillment or production delays and downtime, the National Safety Council projects that workplace injuries accounted for a loss of $171 billion in the United States in 2019. Not surprisingly, many facilities are upgrading their equipment to help reduce existing risks. Forward-thinking facilities are going a step further, however, by investing in smart equipment and controls that can help them make data-informed decisions around safety protocols and training to ensure employees return home safely at the end of every shift—today, tomorrow and in the future.

Industrial Internet of Things and Dock Management Software

Loading docks are one of the most critical and dangerous links in any supply chain. Often the busiest area of a facility, they are a constantly shifting jigsaw of human and machine activity with semi-trucks, forklifts, pallet jacks and AGVs interacting. The growth of online commerce is only increasing the pace of those interactions. It is no wonder that almost 25 percent of all industrial accidents take place in the shipping and receiving zone.

Internet of Things (IoT) technology is moving rapidly into the world of industrial facility management. The Industrial Internet of Things (IIoT) applies various sets of hardware working together to enhance the manufacturing industrial process. This focus allows companies to increase energy efficiency, streamline communication, enhance productivity and monitor events. Real-time and historical safety events can be communicated to safety managers through text and/or email alerts. Through an analysis performed by the IIoT platform, this data helps companies identify trends, training opportunities and employee behavioral improvement through data-driven decisions.

There are various IIoT platforms able to tap into tremendous amounts of data provided by smart equipment at the loading dock and inside the plant. Some go beyond capturing data to provide managers with operational insights that eliminate risky patterns and procedures. Such data analysis can help managers determine if intersections in a facility are becoming too congested or if a mistakenly opened dock door are isolated incidents or recurring problems that need to be preemptively addressed before a devastating accident occurs.

Facilities with newer equipment that have sensors might already have the capability to tap into an IIoT network. When used to its full potential, this smart equipment can be IIoT-enabled to provide invaluable data.

Starting with a Push of a Button

For facility managers to tap into the power of IIoT, they need to have the right equipment in place. Starting at the loading dock, this equipment includes a vehicle restraint to secure a trailer, a loading dock leveler to bridge the gap from facility to trailer during loading/unloading and loading dock doors to help maintain environmental control.

These pieces of equipment serve functions that were once manual. Vehicle restraints can now automatically engage rear impact guards (RIGs) instead of workers having to place wheel chocks. Hydraulic loading dock levelers can be lowered or raised with a push-button instead of workers having to use a pull-chain. Loading dock doors can be operated with buttons instead of manually being opened or closed.

Using logistics equipment at the loading dock once required hard labor. Now it can all be operated with the push of a button. And through additional advancements, it can all be operated much more safely, too.

Interlocking Controls and Safe Sequence of Operation

The development of programmable, interlocking controls at the loading dock has helped make a notoriously dangerous part of any facility into a much safer one. By linking the vehicle restraint, dock leveler, overhead dock door and dock barrier together, dock controls can be programmed to work only in a safe sequence of operation. This allows facility managers to prevent accidents due to improper usage—saving facilities money and costly downtime in the long run.

Integrating multiple loading dock operations into a simple, centralized control system makes it easier for loading dock attendants to perform docking operations safely and quickly. For example, an interlock system disables the use of a hydraulic leveler, overhead door or dock barrier until the vehicle restraint has achieved a safe engagement. Advanced systems also can tap into IIoT when enabled to provide facility managers insight about potential safety risks or areas for improvement.

Visual safety features are available on some control panels, as well. Exterior camera views of the vehicle restraint and landing gear for spotted trailers deliver real-time trailer status to the embedded monitor, helping to keep boots off the ground outside on the drive approach.

Clear Communication at the Loading Dock

Red/green interior and exterior dock lights are the most ubiquitous tool for communication and safety at a loading dock. A green light on the control box inside indicates to a forklift that the trailer is locked and safe to enter, while the corresponding red light outside tells the truck driver it is not safe to pull away (and vice-versa). However, these interior lights are not always visible, as stacked pallets can obscure a lift driver’s view. Thankfully, advancements in LED light communication systems have addressed this issue and more.

Hazard recognition systems that incorporate the newest technologies can offer safety solutions inside the loading dock area and outside the loading dock area on the drive approach. This combination of components uses motion detection, line-of-sight notification and audible alarms to provide hazard recognition and communication to people on and off forklifts. Working in tandem, these safety tools help create a safer, more productive loading dock environment, both inside and outside, by keeping people a step ahead of the potential dangers in their path.

Outside the dock opening, from a fixed location above the dock door, a sensor detects the motion of a tractor-trailer backing into a dock position. A visual and audible alarm located in the vehicle restraint, or mounted as standalone box, alerts dock workers and pedestrians in the drive approach of the impending danger. This multisensory alert system is particularly important because ambient noise often masks the sound of a cab’s noisy engine, which can be 70 feet or more from the back of the trailer.

Inside the dock area, motion-sensing technology can trigger a bright blue light that projects onto the dock leveler when it detects material handling equipment or a pedestrian’s presence inside the trailer. An advanced system also will work in conjunction with the vehicle restraint to alert any dock worker or forklift that enters an unsecured trailer. An integrated vehicle restraint will keep a trailer secured if motion is detected inside the trailer. 

A blue-light flickers as an audible alarm alerts the unsuspecting dock worker that they have entered an unsecured trailer, while the external light system simultaneously changes to red, warning the truck driver that there is activity inside the trailer.

Also on the inside of the loading dock are safety lights located on the upper corners of dock opening. These LEDs provide a clear line-of-sight to trailer restraint status, even if the control box lights are obscured by pallets. LEDs located in the corners of the leveler let workers inside the trailer know the trailer restraint’s engagement status, warning them to leave immediately if the restraint becomes disengaged.

While LED communication at the loading dock is not new, it is often a good starting point for any facility that simply has a red light/green light on the inside and outside of the loading dock. Upgrading to smart equipment in this part of the facility today can reap benefits in the future if a move to IIoT is made down the line.

Traffic Control Inside the Facility

Blind intersections present another safety challenge for facilities. There are several products that address this issue. Instead of the big convex mirrors that obscure reflections in ways that are not to scale, there are a few LED light communication systems designed for blind corners.

There is ceiling-mounted system that plays the role of a traffic light, alerting workers with a red LED stop signal and an amber LED yield signal when something is approaching from another direction. It works by using unidirectional microwave sensors to pick up approaching traffic in all directions, whether it is a four-way, three-way, or two-way intersection. When an object is within sensing range, the other directions on the device show an amber yield signal. The worker approaching the intersection will not be presented with any lights. However, when two or more objects are approaching from multiple directions, those workers will see red LED lights on the device. The remaining directions will show amber LED lights. Advanced models can be enabled with smart technology to capture intersection traffic data, which can be used to develop safety enhancements such as modified traffic patterns or floor layouts. The ends of rack aisles can create similar blind areas in facilities. For this challenge, smaller units that can mount to racks, walls and door jambs can sense traffic moving to protect workers who are using a main thoroughfare to transport goods. Instant communication on possible collision risks allows workers to avoid danger and work more efficiently when they know traffic is not approaching.

Safety Done Right

Making inherently dangerous operations safe is not easy. However, with all the technological advancements being made at the loading dock and inside the facility, there are ways to improve worker safety in the present and help ensure safety in the future.

While cost may be an impediment to safety upgrades for some facilities, many of the products mentioned here are offered as standalone options or can be added as retrofit – providing those facilities with an incremental, budget-friendly equipment integration option. From inside the loading dock and outside on the drive approach to inside the facility, these solutions can help improve safety in the dock operations of any factory, warehouse or distribution center.

This article originally appeared in the February 1, 2022 issue of Occupational Health & Safety.