This sounds like a fuckup with your employer more than a covid issue. So if borders have to close for any reason (war for example) then all of these rigs turn into floating bombs? Why is there not enough manpower? Surely the powers that be just aren't paying enough and not making the right arrangements.
Also, doctors and nurses are probably at higher risk from catching covid and dying than the risk of your rig exploding. These people are now in a potentially deadly profession that none of them have signed up for all because a bunch of selfish twats can't wear some minimal PPE and properly keep to themselves for a couple of weeks.
At the risk of mansplaining...
In answer to your first question? Yes. They do turn into floating bombs. Metal objects when surrounded by salt water tend to rust fairly rapidly when not attended to with constant painting, maintenance, parts replacement and other remedial work. You can imagine how much riskier that gets when said metal objects are filled with explosive gases at incredibly high pressures.
Why is there not enough manpower?
1. The oil and gas industry is an international one. Crews come from all over the world. The bloke whose role I wound up in (after being retrenched from my own full-time position in WA at the start of COVID) was actually based in Malaysia. Some of the key personnel we're missing are based in places as far away as the UK and Canada. Even within Australia, interstate travel has become so complicated and requiring so many exemptions that companies are forced to cut back on the amount of applicants because of the amount of hoops that they are required to jump through
2. Those qualified personnel they
have managed to get in as replacements also have to quarantine both on the way into work and on the way out. Depending on location of the site and the home address of the person a 3 - 4 week swing offshore may require as much as 4 weeks in quarantine. That means you have a need for almost twice as many workers as per normal because if one bloke is in quarantine and his back-to-back is on leave, then there's nobody actually on the job site. Unfortunately the availability is more like half.
3. The attrition rate is through the roof. Staff used to 2 - 3 weeks away from home at most are spending up to 8 weeks away
every trip and if they're coming from states like WA they've also got the added stress of occasional additional spells in home isolation because their home state has decided to play hard ball because of a single positive case in an area where they may just have transited through.
This has an effect in two ways. First off, People just quit, leaving us even more short-handed. Secondly those of us who are left are seriously mentally fatigued and often burnt out. That's not a recipe for success if you're building scaffolds, performing heavy lifts, operating high-pressure equipment, swinging off ropes etc. etc.
Then you can add in all the supply chain issues that are affecting every industry, constant dicking around with flights and schedules, reduced support from the beach because the engineers and admin people are all working-from-home, and for a lot of staff the stress from partners who are having to raise the kids during lockdown alone for months at a time.
It's an absolute fucking shit-show and the general ignorance of most people as to what's happening not just in my industry, but also all the others that are working to ensure that everyone can keep the lights on and still get their mail order bike parts arriving on time, tends to trigger me.