Speaker A
this episode is brought to you by Errol Oh the world's first decent store to offer affordable local data packs in over 190 countries and regions hello everyone welcome to another episode of study call the chief McCoy in this
A seafarer-hosted explainer on whether ship-produced freshwater is safe to drink, covering distillation, chemical dosing, mineralization, chlorination and UV sterilization.
Key Takeaways
- Ship drinking water is treated through multiple barriers: chlorination, mineralization, and UV sterilization.
- Evaporator chemicals are claimed not to contaminate the freshwater output because they remain in the heavier brine.
- Mineralization is important because distilled water lacks essential minerals and tastes flat.
- Regular tank maintenance is critical to safety; visibly dirty or cloudy water should not be consumed.
What the video covers
- Ships have a dedicated drinking water line separated from the domestic freshwater line, both sourced from the same freshwater generator (distillation plant).
- Water is stored in a drinking water tank that is regularly cleaned and dosed with chlorine tablets or other suitable disinfectants.
- Water is pressurized in a hydrophore tank, which acts as an accumulator to keep pressure within a specified range.
- The water passes through a mineralizer that adds trace calcium and magnesium, restoring minerals removed by distillation.
- A UV sterilizer (roughly 185-284 nm) neutralizes bacteria and microorganisms before distribution to drinking fountains and ports.
- Evaporator treatment chemicals (polymers and anti-foam agents, about 20 ml per ton) are injected during production; the host argues they bind to salts and stay in the brine rather than carrying over into freshwater.
- Distilled water lacks minerals, so drinking it alone could cause electrolyte imbalance and make water slightly acidic; the mineralizer addresses this.
- Tanks are manually cleaned at least every six months or as needed to prevent contamination.
- Many seafarers remain skeptical, but the host personally drinks ship water unless it looks dirty or cloudy.
- The episode includes a sponsored segment for Airalo's eSIM data plans.
Chapters
- 00:00Introduction and sponsor segment
- 01:04Separate drinking water line and system overview
- 01:58Drinking water treatment process
- 02:54Evaporator chemicals and contamination concerns
- 04:03Sponsored segment on eSIM data plans
- 05:31Mineral deficiency and mineralizer
- 07:39Microorganisms, tank cleaning and UV sterilization
- 10:36Final verdict and closing remarks
Full Transcript — Download SRT & Markdown
Speaker A
episode we will find out if the water produced by ships is safe to drink in the previous episode I showed you how ships convert seawater into fresh water by means of the distillation plant you saw the process that the seawater goes
Speaker A
through in order to get rid of the salt content until finally going to the ship's freshwater tanks when the salinity has dropped below 10 ppm but it's to this water safe for humans to drink well ships are required to have a
Speaker A
dedicated drinking water line which is separate from the domestic freshwater line that means they are designed to carry potable water and regulations are actually very strict in making sure that the drinking water line is isolated and with no possibility of getting a cross flow from the domestic water line but
Speaker A
even though it is the case for ocean-going vessels the water flowing in both the domestic and the drinking water line is actually produced from the same source which is the freshwater generator so the question of whether it is safe to
Speaker A
drink or not has generated a lot of differing opinions and most of them are from seafarers themselves but before we dive in to the detail explanation let me first show you the process that the distilled water has to go through before
Speaker A
being considered s potable from the fresh water generator water is delivered and stored in the drinking water storage tank which is regularly cleaned and dosed with chlorine tablets or other disinfectants which are suitable for drinking water from there it is suction by the drinking water pump and stored
Speaker A
again in a Hydra for tank this Hydra for tank is just a small tank which is kept pressurized at around 5 bar by means of a pocket of compressed air pushing down on the water this small tank actually serves like an accumulator which keeps
Speaker A
the water pressure always within the specified range all throughout the drinking water from the hydra four tank the water passes through the mineralize ER where it will absorb trace amounts of minerals like calcium and magnesium after that it will pass through the UV sterilizer
Speaker A
where it will be exposed to ultraviolet radiation which will effectively kill any bacteria and other microorganisms in the water from there it will be distributed to the various ports and drinking fountains all over the ship seems pretty straightforward right so is the water safe to drink as I have
Speaker A
mentioned there has been a lot of skepticism as to whether the ship's drinking water is safe for human consumption primarily from the seafarers themselves one of their biggest concerns is chemical contamination because the evaporator side of the distillation plant gets injected with a chemical
Speaker A
solution and they're afraid that the chemical also gets evaporated and gets mixed with the fresh water production okay first of all yes there is a chemical that gets injected into the evaporator while production is going on and the rate of injection is around 20 milliliters per ton of fresh water
Speaker A
produced this liquid chemical is a blend of polymers and anti foam agents designed to control scale formation and foam and evaporators now a few the viewers from last episode made comments about salt buildup in the evaporator tubes and yes that happens especially if the evaporator is not cooled down
Speaker A
sufficiently before shutting down and even if proper shutdown procedures are followed scale build-up will still happen gradually this chemical this evaporator treatment was designed to slow down that specific process in order to maintain the efficiency of the evaporators heating surfaces
Speaker A
in any case the polymers in this chemical while still in liquid form will bind with the scale forming salts in the seawater and prevent them from sticking to the surface of the evaporator tubes the anti form agents on the other hand
Speaker A
minimizes carryover of salt molecules with the water vapor thereby maintaining the district quality now since these chemical agents bind with salt and other molecules in the sea water they basically become heavier so no they won't evaporate and rise up together with the water vapor they just float
Speaker A
around in the Brian until they eventually get suction by the inductor and discharged overboard so again no the chemicals do not contaminate the freshwater production however there are a few other issues which brings doubt as to whether the ship's water is safe to drink and we'll discuss that right after
Speaker A
this break if you frequently travel to different countries like seafarers do I'm pretty sure that one of the first things to do is to buy a local SIM card in this day and age it is imperative for most people to be online and to stay
Speaker A
connected but sometimes switching between SIM cards can be a hassle and there might be instances wherein you won't even be able to buy one it's a good thing there's air alone the world's first eason store to offer affordable
Speaker A
local data packs and over 190 countries and regions the ECM is a new technology which no longer requires phones to have a physical SIM card by using air alone you can simply use your smartphone to buy on top of data plans in foreign
Speaker A
countries at affordable rates it's as simple as going to air low comm purchasing their eason and adding the data plan in your setting you can also do this through the air little app that's available on the Apple in Google
Speaker A
store you can even have multiple country plants on your phone at the same time fish on the required country geese in and still be contactable from your existing phone number so say goodbye to the hassle of trying to find where to
Speaker A
buy local SIM cards in whatever country you go to air low gives you the freedom to connect with who and what matters the most wherever you may be for more information visit air low calm and try out your
Speaker A
first ECM today link is down in the description one of the other issues is that the still water doesn't have minerals like calcium and magnesium which are very important for the human body so drinking distilled water alone will not replace the salts and minerals that are lost through swept and
Speaker A
urination and may cost electrolyte imbalance also removing the minerals from water will tend to make it acidic or at least almost acidic and that can't be good for our bodies to specifically address the problems associated with lack of minerals the drinking water line is equipped with what we call a mineral
Speaker A
eyes err it's basically just a filter which contains a medium composed of the naturally occurring minerals that can be found in freshwater you know calcium magnesium maybe a little bit of potassium and other stuff so the distilled water will pass through this medium and absorb trace amounts of these
Speaker A
minerals thereby regaining what was removed through the purification process and by the way distilled water has a flat taste it you might find weird so in a way the minerals actually provide a little bit of flavour and makes water taste like well water but what about germs you know
Speaker A
like bacteria and other microorganisms in the water that can really make you sick how can they be removed bacteria and other microorganisms tend to thrive if the tanks are dirty or become contaminated for some reason as part of regular maintenance onboard ships to
Speaker A
freshwater tanks are emptied and manually cleaned at least every six months or has needed depending on the freshwater condition coming out of the faucets moreover the dedicated drinking water tank is dosed in chlorine tablets or some other disinfectant which can safely
Speaker A
be used for drinking water additionally on the final stage of the drinking water line is the UV sterilizer that's UV s an ultraviolet it's basically like an enlarged pipe which has a germicidal lamp inside now this lamp emits a high frequency ultraviolet light usually with wavelengths between
Speaker A
185 to 284 nanometers which is deadly to bacteria and other microorganisms so when the water passes inside the sterilizer it gets exposed to the UV radiation and whatever microorganisms were swimming in that water will be effectively neutralized after passing through the sterilizer the drinking
Speaker A
water is now ready to be distributed to the water fountains and to the faucets ready for drinking by the way another safety precaution that is being required nowadays is to periodically send a sample of the ship's drinking water to a
Speaker A
laboratory for analysis some ships are also supplied with the portable testing kit so that the crew can test the water themselves as a reference point this test is being required in order to determine if the water produced by the
Speaker A
ship is free from contaminants that can be harmful if consumed so after going through all of that process the question remains is the ship's water really safe to drink again many seafarers are still uncomfortable about the prospect of drinking the water produced by the ship it has actually
Speaker A
come to the point that most of them prefer to buy bottled water which is an additional expense coming out of their pocket or deducted from the provision budget the funny thing is they spent all that money to avoid drinking the ship's
Speaker A
water but when the galley serves juice they still drink it or if the ship is fitted with an icemaker they still get ice from there and where do you think the water to make the juice and ice comes from I guarantee it's not
Speaker A
from bottled water personally I myself drink the water produced by the ship I have always done so unless there's an obvious reason not to drink it like if the water is visibly dirty or even a bit cloudy of course I won't drink it but in
Speaker A
all the years I've been working on a ship I've been drinking the ship's water and I'm still alive and never got sick while I'm on water ship the way I see it as an engineer I am in charge of the fresh water production process and I
Speaker A
know what happens to the water after passing through each stage so as long as the process is strictly carried out and everything is maintained the way it's supposed to be I would say yes it is safe to drink the water produced by the
Speaker A
ship I hope you enjoyed and learned something today there will be more topics to discuss in our future episodes but for now class dismissed
Topics:ship waterpotable waterdistillation plantdrinking water safetyUV sterilizermineralizerseafarersmarine engineeringfreshwater generatorchlorination
