About 2,100 members of the Parcel Delivery Workers' Solidarity Union, out of the total 6,500 members, skipped work to join rallies from last Wednesday (June 9), after the union's talks with the government and major logistics firms fell through.
An agreement was reached in January after delivery workers went on strike to demand better rights and protection in the wake of a record-high 16 deaths among them last year, all blamed on overwork.
Firms including CJ Logistics, Lotte Global Logistics and Hanjin Transportation had promised to implement measures to ease the burden on exhausted delivery drivers, such as hiring more workers to sort parcels or using technology to automate the process.
But they failed to keep their word.
Union officials said that logistics firms have "gained enormous benefits for decades" forcing delivery workers to sort parcels for hours "for free".
They argue that parcel sorting should be a separate job since most couriers are hired on contract and paid based on the number of parcels sent, not the number of hours clocked.
"Logistics firms must take responsibility... and immediately implement the overwork prevention measures," an official said.
The union said on Sunday that it will continue to strike in Seoul this week, deploying up to 6,500 members and their vehicles on some days.
Meanwhile, e-commerce giant Coupang, widely known as South Korea's Amazon, is also facing mounting public pressure to treat its directly hired delivery workers better, after one of them became the 17th such death in March this year.
Before the pandemic, only one to four couriers died every year, according to government data.
Last month, Coupang announced plans to allow its delivery workers to take a month's paid leave when they need to rest, as part of efforts to "improve working conditions for all drivers in the Korean logistics industry".
There are about 40,000 delivery drivers working in South Korea. They have long complained of overwork and the situation became more serious last year after a surge in demand for their services.
A total of 3.37 billion parcels were delivered last year, marking a 21 per cent increase as more people switched to online shopping during the pandemic.
The food delivery market saw explosive growth of 79 per cent to reach 17.4 trillion won (S$20.7 billion) last year, as people shunned dining out after infections spiked.
Nowadays, delivery workers are known to work 12 to 14 hours a day - up from 10 hours before the pandemic. They can make up to 600 deliveries a day.
Of the 16 deaths last year, some died of a heart attack while others suffered brain haemorrhage.
One driver took his own life last October, leaving behind a note: "I'm too tired".
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