MRO Magazine

The Great Escape: Supply-chain sustainability starts at the loading dock


August 22, 2011
By PEM Magazine

The idea of going easy on the earth is becoming a fact of Canadian corporate life, and the supply chain plays a major role in these efforts. According to a recent Deloitte survey, 80 percent of Canadian supply chain professionals define green supply chain management as a corporate strategic priority.

According to research, the supply chain represents as much as 40 to 60 percent of a business’ environmental footprint. Consider the energy required for shipping goods, which include heating and cooling the distribution centre and fueling the trucks that transport products to their destinations.

If a company is not involved already, it won’t be long before it is mandated to improve, and opportunities may be found in areas such as material selection, product design, production process, customer use experience, and disposal/recycling options. A holistic awareness of the supply chain and its impacts is the foundation for companies that want to reduce risks and seize opportunities. As management scrutinizes the distribution centre to find small and large adjustments that will allow it to run a more energy-efficient business, attention eventually focuses on the loading dock.

Where else in a facility are there eight-foot-by-ten-foot holes on the wall? If the size of those holes isn’t challenging enough, consider their purpose, which is to allow forklifts to access the trailers parked at the door.


For many reasons, a hard-working dock area presents challenges when it comes to blocking air escape and invasion. If dock doors are not sealed properly, energy losses can be in the thousands of dollars, easily busting the operating budget and defeating the good intentions of the sustainability program.

Completely sealing the dock doorway requires a four-pronged attack.

1. At the Doorway
Forklifts are essential for truck loading and unloading, and a five-ton vehicle cruising within a confined space often results in damage to dock doors, especially those of standard design.

Similar to the door on a residential garage, dock doors are hardly a match for a forklift collision. Even when the door is not completely damaged or the guide rollers have not popped out of the door guide, a punch from a forklift can misalign the door panel and create costly gaps.

A traditional door style may be fine for low-usage docks, but for truly busy operations, “impactable” dock doors will save the maintenance budget and boost the building’s energy efficiency program. As the name implies, impactable dock doors do not resist the force of the blow when taking a forklift hit; instead, the door panel releases from the door guides. A quick pull sets the door back in place, making it operational in just minutes and once again protecting the doorway.

In addition to energy saving initiatives within the building, managers are looking to reduce truck idling time. Quickly restoring a door to operation and making sure a doorway is available for scheduled trucks minimizes that issue.

2. Along the Floor
Standard pit-mounted dock levelers provide safe trailer access for forklifts, but the nature of their design creates passageways for air infiltration and escape. The concrete pit design suffers from small gaps between the edge of the dock leveler and the pit wall, exposing the facility to interior–exterior airflow exchange.

There is a solution for this energy loss. Both new and existing pit-style dock levelers can be outfitted with an advanced weather-seal system composed of durable open-cell foam and heavy-duty vinyl.

This system effectively fills the gaps around the sides and rear of the dock leveler and provides a superior seal around the perimeter. For additional protection against energy loss, steel dock leveler platforms can be coated on the underside with spray foam insulation to minimize the platform’s ability to conduct heat.

3. Between the Wall and the Truck
Ideally, a truck trailer would fit precisely within a doorway, but even then, the facility must provide a means for sealing that gap.
Most docks have seals or shelters to create a mini-tunnel, and these flexible structures must withstand damaging force and compression when the semi backs up to the wall. Dock seals and shelters are critically important components in containing conditioned air in the dock areas.

Seals with galvanized steel backing offer many advantages over the wood backing used on some models of dock seals and shelters. Wood backing has a solid mass (1½ inches thick) that does not yield when the seal is compressed. Impact often results in damage to the building.

With steel backing, the solid mass is replaced with compressible foam on a steel frame. Steel backing also offers superior durability because it does not rot, split, crack or warp. It uses plated screws with load-spreading washers in the steel to provide a stronger, more durable hold on the fabric.

Truck restraints provide greater protection than wheel chocks for forklift drivers by preventing trailer creep, and they add an extra measure to the doorway seal. If the truck is allowed to “walk” away from the wall, the doorway seal becomes less effective than one that is snugly held tight to the dock doorway.

4. Above the Floor
Proper lighting on the dock and inside the truck trailer prevents injuries and damage to product. Changing out incandescent lights with LED bulbs can make a significant difference in energy usage, reducing it by as much as 69 percent. Switching out 100 incandescent lights with LEDs can save nearly $60,000 over the life of the bulbs.

A standard lighting fixture has the potential to suffer damage from a forklift. Dock managers have the option of changing out just the bulbs or installing a light arm and head that is ruggedly designed to withstand the dock environment.

Further toward the ceiling, high-volume/low-speed (HVLS) fans improve worker comfort and contribute to energy savings. These fans move a massive amount of air using a small amount of electricity. Fans control energy usage by enabling the facility to raise its thermostat by about eight degrees in the summer and lowering it in the winter. For every degree the thermostat is lowered, facilities save about three percent on their total energy bill. For an even more energy-efficient option, facilities can use solar energy to power fans, allowing them to operate off the grid.

Take Control
While installing this equipment is the first step, orchestrating equipment operation ensures that the dock offers protection for both dockworkers and the energy program. Master control panels combine the separate controllers that raise and lower dock levelers, engage the truck restraint and track door closing — ensuring everything happens in its proper order. In addition, having the necessary buttons and switches on one box reduces conduit run along the already tight dock wall.

Software-based yard and dock management systems enable a facility to integrate with other intelligent software systems to monitor, schedule and communicate trailer movement, load assignment and loading-dock status.

Along with keeping an eye on whether doors are open or closed, these systems provide truck–trailer coordination. This enables dock management to direct and coordinate yard traffic for maximum efficiency and to reduce fuel use by idling trucks.

The building envelope is key to a successful sustainability program, especially considering the amount of heat needed to withstand Canadian winters. A properly deployed loading dock system will enable operations to achieve both peak energy efficiency and peak truck traffic organization. Product enters and leaves the facility through the loading dock, and it is there that supply-chain sustainability begins.

Steve Kalbfleisch is sales manager with Dock Products Canada.