SINGAPORE - Mr Shaun Gerald D'Souza was part of a team helming natural gas tanker sailing from the United States to Indonesia in May last year when one of its crew members tested positive for Covid-19.
The stricken electrical officer's oxygen level plummeted to below 95 per cent.
Medical oxygen supply on board was running low and the ship was still many days away from land, forcing Mr D'Souza, 36, to think on his feet.
"We were running against time," said Mr D'Souza, a chief engineer at Executive Ship Management, which is headquartered in Singapore.
"We had the option of reducing the flow rate of the medical oxygen to prolong its usage, but his oxygen levels did not seem to improve with a lower flow rate."
"I heard that industrial oxygen could be used as a back-up, but was not completely sure as it could have contaminants. After a bit of reading up and discussions, we decided to use it with additional measures, like having the industrial oxygen bubble through a water column to remove any contaminants as there was no other option," said Mr D'Souza, who has been sailing for 16 years.
Industrial oxygen has a 99.5 per cent concentration, compared with the near 99.9 per cent of medical oxygen.
Mr D'Souza used the water column as a humidifier and a filter, and changed the water every two to four hours to keep the supply clean.
The adapters of the industrial oxygen were also different and required some quick tweaks on the spot so that there would be no leaks.
All this time, while managing the crisis, Mr D'Souza was powering the ship through "one of the harshest" sailing conditions to get the ship to a meeting point so that the electrical officer could be airlifted to receive medical attention.
"We pushed the engines to their maximum limit to reach the rendezvous point just in time before the sun set at 5pm. We would otherwise have to wait for the next morning," Mr D'Souza said, describing gale-force winds and high waves.
The electrical officer was airlifted to Namibia and then flown to one of the best hospitals in South Africa's Cape Town, where, despite the ship crew's valiant efforts, he succumbed to Covid-19 two weeks later.
Recounting the incident, Mr D'Souza said it was the first time the crew members had to deal with a Covid-19 case on board, even if they had been briefed on precautionary measures and actions to take if someone was suspected or confirmed to have the disease.
Living and working in such close proximity meant that a potential cluster erupting was a very real threat.
The clusters that emerged on board other ships, such as the Diamond Princess cruise with some 700 Covid-19 cases in February 2020, weighed heavily on everyone's mind.
For his valiant efforts, the Maritime and Port Authority of Singapore (MPA) honoured Mr D'Souza with the MaritimeSG Care Award in November last year.
The award was also given to 49 others for keeping the industry afloat in the challenging conditions of Covid-19.
Another recipient of the MPA award was Ms Michelle Soh, 32, a crewing superintendent at Wilhelmsen Ship Management Singapore.
She was lauded for taking the initiative to keep crew members and their family informed when some of them were stuck on ships with no end to their stint in sight.
As countries struggled to develop protocols to change crew in the early phases of Covid-19 in 2020, she made daily calls to various vessels to address the crews' concerns.
She was transparent about the challenges of crew change at a time when countries were all erring on the side of caution.
"At the peak of the pandemic at one point, our global statistics of overdue crew was at 40 per cent. Our crew's anxiety was understandable as each passing day was one day too many," she said.
"The greatest achievement was when we successfully performed a crew change... a tired crew got to go home and be reunited with his family and the reliever could continue to provide income to support his family."