KENT — Depending on where you stand in Amazon’s Kent warehouse, customer orders are either moving over your head or under your feet.

With 18 miles of conveyor belts, millions of items in the warehouse at any given time and an operation that runs 24 hours a day, workers inside are never far from the goods they’re helping to get to customers’ doorsteps. 

Amazon opened the nearly 1 million square foot warehouse in 2016 — its fourth facility in Washington at the time — where workers pick, pack and ship small items, such as books and electronics. It is shaped like a “U,” with boxes of goods coming in on one end of the letter and exiting as customer orders on the other. In between, items swoop through the warehouse on a journey that includes conveyor belts, autonomous robots and, for some, a machine that will customize a box to fit its dimensions so snugly it barely needs tape.

The Kent facility had its biggest day in December 2020, according to a banner hanging proudly above one of the loading docks declaring it had shipped 1.2 million packages on Dec. 18 that year. 

This March, the same facility became the subject of workplace safety concerns for Washington’s labor department.

The regulatory agency fined Amazon $60,000 for “willful” safety violations. Amazon “did not make sure that employees were provided with a workplace free from recognized hazards,” the Department of Labor and Industries wrote in its citation. Warehouse workers must lift, carry, pull, push, twist, bend and reach in combinations that “have caused, and are likely to continue to cause” injuries, it wrote. 

Because the department has cited Amazon for similar violations in the past at other Washington facilities, the company is aware of these hazards, officials said at the time, and is “knowingly putting workers at risk.”

Amazon has appealed the citation and says “we strongly disagree with [the] claims and don’t believe they are supported by the facts.” Almost six months after issuing the citation, it is still in the appeals process, according to a spokesperson for the labor department.

On a recent tour in July, the warehouse was still processing orders from Amazon’s Prime Day, the annual two-day sale that sold more than 300 million items this year.

Workers in the “U”-shaped building in Kent were starting to see a split in who felt the strain from Prime Day: Workers on one end of the letter, where goods are brought into the facility from trailers, had finished the prep for Prime Day, unloading and storing items for customers to buy. On the other end, where orders are packed into boxes for customers and shipped closer to their final destination, workers were still in the height of the shipping frenzy. 

Amazon’s Kent warehouse has 44,000 yellow totes used to move items through the warehouse and about 3,000 employees.

Trucks coming into the building are dropping off items that will then be processed and stored, waiting for customers to click buy. Trucks going out are filled with packages that hold a customer’s order, whether that’s a single order or a combination.

Deliveries arrive at a pre-scheduled time and Amazon has an algorithm that helps determine how long workers will need to load or unload each full truck. 

Inside the warehouse, an item is “stowed,” or scanned and placed in a yellow storage bin, then takes a ride on the “robotic super highway” as Amazon’s autonomous robots move items from one worker to the next. The highway is a zone exclusively for robots that use a series of bar codes on the floor to navigate from one workstation to the next.

Workers stow items at random to maximize efficiency and prevent a robotic traffic jam if popular items were clustered together.

Items then move through a network of containers and conveyors: out of the yellow storage bin, into a yellow storage tote, onto a conveyor belt, into a package, onto a conveyor belt. Machines then seal, scan, weigh and address boxes.

From there, packages head to one last ride on a conveyor belt where they are scanned (again) and sent down a long straightway. While moving, a gadget that Amazon calls a “shoe” will push out from the side of the conveyor belt and sweep packages down chutes that deliver them to the appropriate truck. 

In Kent, some orders are rerouted to a different set of conveyor belts where Amazon is testing out new technology meant to reduce the amount of packaging used for each delivery. There, a machine scans goods coming down a conveyor belt and then builds boxes unique to each item’s dimensions. It is meant to reduce the amount of cardboard and tape needed to seal a box and the number of workers needed to get it out the door. 

Amazon declined to say how many automated packaging machines it is testing or how much packaging it expects the machine will save.

More than a year after Washington’s workplace safety regulators began inspecting Amazon’s warehouses, federal regulators are now also beginning a civil investigation into working conditions at the company’s fulfillment centers. In July, the Occupational Safety and Health Administration inspected Amazon warehouses outside New York City, Chicago and Orlando, Florida.

Amazon’s warehouse employees work four days on, three days off, for 10 hours at a time. A sign on the wall at the Kent fulfillment center reminds them there is a 58-hour limit to the workweek.

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