Cruise ship hot tubs - safe or not?

[chengkp75]

6 hours ago, resetjet said:

10 ppm is total chlorine.  We tested it on a carnival cruise and it had zero free chlorine.  (Unsafe). Really 1 ppm free is unsafe in a hot tub.

No, the sensors measure "residual" chlorine, which is the free chlorine level after the water comes back to the pump from the hot tub, and some of the chlorine has been used up in sanitizing.  It is the amount of "free chlorine" that has not been used up.  If there was 0ppm of residual chlorine, the ship would be in serious trouble at the next USPH inspection, as the recording charts are kept for a year for review.

[chengkp75]

6 hours ago, wreckem2013 said:

They make these things called salt water generators(aka salt water pools) that make maintaining chlorine levels easy without pucks or liquid chlorine.

Chlorine generators are not approved by the USPH/CDC for use in cruise ship recreational water facilities, because they don't react to changes in bather load as quickly as the chlorine and pH meters and liquid dosing pumps do.

[Mapleleafforever]

15 hours ago, Tapi said:

On MSC, you may be pleasantly surprised. They have a category of entry level suites that have their own whirlpool tubs. 
 

Between MSC’s loyalty match program (where they match your loyalty status on a any other cruise line for an additional discount), and other promotions they offer like “kids sail free”, having your own whirlpool tub may be more affordable than you think. 
 

To give you an idea, here’s some sample pricing straight from their website for a cruise we have booked on the MSC Seashore (one of their newest ships) for June 2024:

Off topic but......we've checked out MSC briefly and based on pricing alone we're willing to give it a try. Is the overall cruise experience similar to Royal's? 

[Mapleleafforever]

The high chlorine content of the hot tubs also acts as a "degreaser" to assist people with dissolving the hard to reach crunchy bits left over that the cruise line TP couldn't get off. 

[Tapi]

17 minutes ago, Mapleleafforever said:

Off topic but......we've checked out MSC briefly and based on pricing alone we're willing to give it a try. Is the overall cruise experience similar to Royal's? 

Some things are similar, some things are vastly different. 
 

One thing where I consider MSC and Royal  to be similar is in the “wow” factor of their newest and largest ships. In fact, I had never sailed on any ship that came even close to Royal’s Oasis class until I sailed on MSC. Their new World class ships close the gap further in terms of size and amenities. They even have 2 deck loft suites, inside facing balconies and their version of The Abyss. 
 

In general, their ships are beautiful, tastefully appointed, with tons of activities, great program for kids and teens, specialty dining etc. 
 

The biggest difference you’ll find is in their service and fellow passengers. MSC caters heavily to an international clientele, more specifically European. You’ll still sail with a large percentage of Americans, but you’ll notice that announcements, activities, and some cuisine selections cater to a broader clientele. Don’t be surprised to hear important announcements made in 7 languages in rapid succession.
 

Service tends to feel a bit more aloof (probably a cultural difference). They are there for whatever you may need, but they’re somewhat stoic, not in your face, happy, cheery like when you cruise on American lines, so some may come across as being uninterested. But it’s not the case. The more international vibe is actually one of the things that I love about MSC. 
 

Don’t forget to sign up for their loyalty match program. Whatever highest status you have on any cruise line or hotel chain, they’ll match it to their similar status level. This will give you an additional 5% discount off your cruise fare.

 

Overall, it’s a great product. I’ve truly enjoyed sailing on them.  

Edited March 30, 2023 by Tapi

[Mapleleafforever]

1 minute ago, Tapi said:

Some things are similar, some things are vastly different. 
 

One thing where I consider MSC and Royal  to be similar is in the “wow” factor of their newest and largest ships. In fact, I had never sailed on any ship that came even close to a Royal’s Oasis class until I sailed on MSC. Their new World class ships close the gap further in terms of size and amenities. It even has inside facing balconies and their version of The Abyss. 
 

In general, their ships are beautiful, tastefully appointed, with tons of activities, great program for kids and teens, specialty dining etc. 
 

The biggest difference you’ll find is in their service and fellow passengers. MSC caters heavily to an international clientele, more specifically European. You’ll still sail with a large percentage of Americans, but you’ll notice that announcements, activities, and some cuisine selections cater to a broader clientele. Don’t be surprised to hear important announcements made in 7 languages back to back.
 

Service tends to feel a bit more aloof (probably a cultural difference). They are there for whatever you may need, but they’re somewhat stoic, not in your face, happy, cheery like when you cruise on American lines, so some may come across as being uninterested. But it’s not the case. The more international vibe is actually one of the things that I love about MSC. 
 

Dint forget to sign up for their loyalty match program. Whatever highest status you have on any cruise line or hotel chain, they’ll match it their similar status level. This will give you an additional 5% discount off your cruise fare.

 

Overall, it’s a great product. I’ve truly enjoyed sailing on them.  

Excellent, thanks for the info!! Sounds like a must try....at least once. Good to have other options. 

[Tapi]

1 minute ago, Mapleleafforever said:

Excellent, thanks for the info!! Sounds like a must try....at least once. Good to have other options. 

Yes. That’s how I approached it. I was going to sail on them just once to give them a try because I came across a deal to good to pass up. I’m now booked on our 4th one. 😂

[lovesthebeach2]

21 hours ago, Sunshine3601 said:

We used hot tubs for years until my DH had an organ transplant and we met with an Infectious Disease Doctor as part of the transplant team and learned to never use a public hot tub.   

 

I think Royal only empties/cleans the hot tubs between sailings.   

That could be true because we get up very early and when in the Diamond Lounge on those ships that have a view of the pool, we can see the hot tub perfectly and it’s covered by the netting and full of water.  Now it’s possible they drained it at night and refilled and turned on the heaters, but people are in it when it’s not even light yet.

[chengkp75]

6 minutes ago, lovesthebeach2 said:

That could be true because we get up very early and when in the Diamond Lounge on those ships that have a view of the pool, we can see the hot tub perfectly and it’s covered by the netting and full of water.  Now it’s possible they drained it at night and refilled and turned on the heaters, but people are in it when it’s not even light yet.

As I said, the maximum time between draining is 72 hours, per USPH/CDC regulation.  Very typically, when the tub is full and covered with netting, they are allowing the "super-chlorination" to dissipate down to normal operating levels of chlorine, before allowing anyone in.

[resetjet]

3 hours ago, chengkp75 said:

No, the sensors measure "residual" chlorine, which is the free chlorine level after the water comes back to the pump from the hot tub, and some of the chlorine has been used up in sanitizing.  It is the amount of "free chlorine" that has not been used up.  If there was 0ppm of residual chlorine, the ship would be in serious trouble at the next USPH inspection, as the recording charts are kept for a year for review.

Well there was because i measured it.  I will bring my kit next time and do some posts.  If you know sanitation,  you will also know that it is unhealthy to have

more then 10 ppm total chlorine.  Adding more chlorine is not an option.  The only way to fix it is empty the hot tub of people or drain it.  If water is left in,  Super chlorinate it,  unlock the combined chlorine then either wait or add de-chlor to being the level back down to 10 or below.  Somehow i do not see this happening on ships.  The simple fact is that chlorine does not work as well at high temps,  bacteria,  algae and fungi flourish and with the bathing load being higher then design,  its impossible to protect 100% of the time.  Its probably ok most of the time but trust me,  sooner or later you will find one that isnt.  Rashes,  infections,  pimples are the result.  That crew lawyer has it posted on this main page as one of the number one people he represents,  hot tub infections.  

[chengkp75]

15 minutes ago, resetjet said:

Well there was because i measured it.  I will bring my kit next time and do some posts.

Depending on what kind of test strips are used, the pink coloration that determines chlorine level can get bleached out at high chlorine levels, so the strip appears to read zero.

 

As for total chlorine level, it is interesting that home pool and hot tub manufacturers recommend a 1-3ppm level, while the USPH/CDC requires a 1-4ppm level for a pool, and a 3-10ppm level for a hot tub, and the CDC recommends this for all public hot tubs (though they have no jurisdiction over land hot tubs).

 

https://www.cdc.gov/healthywater/swimming/aquatics-professionals/operating-public-hot-tubs.html

[JeffT237]

27 minutes ago, resetjet said:

The simple fact is that chlorine does not work as well at high temps,  bacteria,  algae and fungi flourish and with the bathing load being higher then design,  its impossible to protect 100% of the time.  Its probably ok most of the time but trust me,  sooner or later you will find one that isnt.  Rashes,  infections,  pimples are the result.

 

So to the original question you would say hot tubs are unsafe?  What would your solution be? Take the hot tubs out of service as they're too dangerous or maintain them in a different way to make them safer? 

[Wineaux007]

46 minutes ago, JeffT237 said:

 

So to the original question you would say hot tubs are unsafe?  What would your solution be? Take the hot tubs out of service as they're too dangerous or maintain them in a different way to make them safer? 

I would just stay away from those petri dishes.  🤪

[Sigyn]

None of the conversation here has made me more inclined to sit in a hot tub on the cruise I embark upon in two days. It's been ten years since I sat in a cruise ship hot tub, so I might as well continue the trend. 

[Toddcan]

1 minute ago, njsmom said:

None of the conversation here has made me more inclined to sit in a hot tub on the cruise I embark upon in two days. It's been ten years since I sat in a cruise ship hot tub, so I might as well continue the trend. 

Based on your original post , no one will be surprised.  

[resetjet]

1 hour ago, JeffT237 said:

 

So to the original question you would say hot tubs are unsafe?  What would your solution be? Take the hot tubs out of service as they're too dangerous or maintain them in a different way to make them safer? 

My suggestion and it may already exist on newer ships is to have a continous system that removes water from the hot tub and replaces it with fresh,  preheated chlorinated water.  This system would be somewhat complex,  especially given the locations of hot tubs on the ship.  It would cost a ton in chlorine and would have environmental impacts(discharge the filthy chlorinated water). But it could be done.  It would also

be possible to have a large tank where the water can go to be superchlorinated and allowed to sit before being reintroduced.  The main problem is a gallon of chlorinated water only has so much santizing capability and its worse at high temps.  The hot tubs are very small,  hot and packed with people.  
 

Again the risk of infection is small,  but it happens and if you went through what i did,  you will never get in another one.  

[davekathy]

Throw a Baby Ruth in the hot tub when no one is looking. 

[JeffT237]

9 minutes ago, resetjet said:

Again the risk of infection is small,  but it happens and if you went through what i did,  you will never get in another one.  

 

I totally understand that, we all modify our behaviors due to our past experiences. 

[Toddcan]

13 minutes ago, davekathy said:

Throw a Baby Ruth in the hot tub when no one is looking. 

[Jimbo]

12 hours ago, wreckem2013 said:

They make these things called salt water generators(aka salt water pools) that make maintaining chlorine levels easy without pucks or liquid chlorine. I only have to add one chemical once a week, about a pint or so of acid to keep the ph around 7.4. It’s easy to maintain a pool even if you use traditional chlorine methods as well. Troublefreepool is a great resource for building and maintaining pools.

We have a salt water generator for our hot tub at home. The water is super clean all the time. Wouldn't get in another hot tub from anywhere without one.

Never feel the need to get in a hot tub on a cruise since we have one at home. 🙂

[RedIguana]

6 hours ago, resetjet said:

The simple fact is that chlorine does not work as well at high temps

The efficacy of chlorine disinfection increases with temperature. It works better at higher temps.

[resetjet]

1 hour ago, RedIguana said:

The efficacy of chlorine disinfection increases with temperature. It works better at higher temps.

That may be true but because it evaporates so fast at high temps it is the opposite effect.  

[resetjet]

7 hours ago, chengkp75 said:

Depending on what kind of test strips are used, the pink coloration that determines chlorine level can get bleached out at high chlorine levels, so the strip appears to read zero.

 

As for total chlorine level, it is interesting that home pool and hot tub manufacturers recommend a 1-3ppm level, while the USPH/CDC requires a 1-4ppm level for a pool, and a 3-10ppm level for a hot tub, and the CDC recommends this for all public hot tubs (though they have no jurisdiction over land hot tubs).

 

https://www.cdc.gov/healthywater/swimming/aquatics-professionals/operating-public-hot-tubs.html

Strips are inaccurate and not allowed to be used by most health departments.  A dpd kit is way better.  Trust me,  i am trained in this area.  There was lots of chlorine cant remember but near 10,  smelled to high heaven from the chloromines and zero free chlorine.  Unless there is some magical system,  the only way to fix it is kick everyone out and shock it or drain it.

[Blur]

7 minutes ago, resetjet said:

Strips are inaccurate and not allowed to be used by most health departments.  A dpd kit is way better.  Trust me,  i am trained in this area.  There was lots of chlorine cant remember but near 10,  smelled to high heaven from the chloromines and zero free chlorine.  Unless there is some magical system,  the only way to fix it is kick everyone out and shock it or drain it.

Not saying who is right or wrong but this gave me a mental image of the subway staff with a clipboard pretending to write down the temp of the area where the veggies were stored for inspection... Lol

 

If it's not automated and digital easy enough to write down what the values are early in the day when everything is good.  Either way if you see kids bobbing for apples in the hottubs prob best to avoid.

 

[RedIguana]

44 minutes ago, resetjet said:

A dpd kit is way better.

Yep, and titration is even better.....