From running a hawker stall to working in a travel agency, she has done it all.
Madam Kelly Tan is, by her own admission, a job-hopper.
But it was not until she joined PSA in 1997 that she found her true calling - operating monster machines.
In the man's world of crane operations, Madam Tan, 45, stands proudly as PSA's sole female quay crane operator.
She started her career with PSA as a prime mover driver - her eleventh job - which saw her transporting 40-footers around the port, but she always wondered what it was like to be off the ground.
She told The New Paper: "When I looked up, I saw all the cranes and wanted to be up there."
So four years later, she made the leap from truck to crane and tried her hand at loading containers using nine-storey-high yard cranes.
She took to it like a fish to water.
She said: "It wasn't easy, but it was more satisfying."
The indomitable Madam Tan then took her love for these machines to even greater heights in 2011, switching to quay cranes, which soared 15 storeys high.
Neither the height nor the male dominance deterred her.
"Gender is never a problem for me.
"At first, all the guys asked me why I wanted to join them. But I joke with them and even join them for nightlife and now, they treat me like their brother."
Female crane operators like Madam Tan are a rare breed and deserve more respect, said secretary of Singapore Cranes Association Frankie Tan.
He told TNP: "This trade is dirty, messy and difficult.
"It's very hard for females to choose it unless they develop a love for cranes."
Madam Tan's love for her job was evident when TNP visited her workplace on Thursday morning.
She was completely at ease up on the towering quay crane, her hands barely grazing the handrails for support.
When asked if she was afraid of heights, she laughed it off: "No such thing."
But beneath her bubbly disposition lies a dead serious dedication to her job.
Like a proud mother, she showed us every nook and cranny of the quay crane cabin - her second home.
Up in the enclosed space that is no bigger than a typical storeroom, where she has nothing but a panoramic view of Singapore's waters for company, she spends a third of the day transporting containers from vessel to truck and vice versa.
But her concentration is such that an eight-hour shift can fly by without her noticing.
"Time passes quickly when I'm focused. When I'm up here, I can see the whole port and I know that I'm doing something important."
Madam Tan also knows that in her line of work, there is no room for error.
"I'm at the front line of operations. If I stop, everyone stops. Any mistake can cost a million dollars."
The dangers of her job are underscored by a recent enforcement operation conducted by the Ministry of Manpower (MOM) between March 16 and April 2.
MOM's inspections uncovered 147 instances of unsafe crane and lifting operations by 55 errant companies.
There was also a string of seven crane-related incidents between Jan 19 and March 9 this year.
But PSA's stance on safety is clear.
Mr Tan Puay Hin, regional chief executive officer, Southeast Asia, PSA International, said: "PSA is fully committed to the safety and health of of our staff and port users in our Singapore terminals and overseas.
"At PSA, we would like employees to come to work and return home safely."
Madam Tan returns home safely to her two proud sons, aged 19 and 21, every day.
Beaming, she said: "When they see a crane, they'll tell their friends, 'My mum works up there.'"
This article was first published on Apr 20, 2015.
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