Holland America Cabin Ventilation - Isolated?

[The-Inside-Cabin]

I have cruised over 75 days since restart and have always been puzzled by who catches COVID and who doesn't.   My casual observation is that people who were very meticulous about masking would nevertheless still get COVID.   This story, from the early days explored the possibility of people getting COVID while isolated in their cabins.  The below post from the Rotterdam Transatlantic talks about improvements HAL: made to the ventilation systems..

 

So i am curious if COVID might still be circulating in the cabins from the air in Public areas and that might explain why some people are getting COVID.

 

I would appreciate an update from @chengkp75on this subject.    Thanks!

 

 

 

https://aaqr.org/articles/aaqr-20-07-covid-0495

 

 

 

 

Edited December 13, 2022 by The-Inside-Cabin

[Florida_gal_50]

I feel I’m very meticulous on a cruise.  Always mask except for eating and drinking.  Wipe down my cabin, cell phone etc with Lysol wipes.  Don’t go to the entertainment, didn’t before either.  I haven’t  got Covid on a cruise or at home ever.

[REOVA]

We are meticulous, wash hands, sanitize, masks, etc but my DW as well as my Brothers DW got Covid on the Zaandam in July (which forever will be the Covid Ship for us - and thanks to the book Cabin Fever). I believe they got it from a food tasting tour where there were multiple people close in a room and they were not wearing masks, eating. (My brother had it 3 weeks prior to boarding so probably had immunity). Myself (knocking wood) never. We had over 200 passengers and many crew during the cruise that got sick over the 35 days. Fortunately I was not one of them. My theory (some scientist stated early) is it takes a specific number of virus cells during a specific time to build up and take over your immune system. Sometimes your system can fight it (mild or no symptoms) and sometimes not. Mask wearing helps but if you touch something with a virus, take your mask off or on and touch your face (ear, eyes,nose, etc) in the process of removing or putting on, you infect yourself and the mask does nothing. Also most people use the same mask for an extended period of time. Hospitals have a 1 time use for a reason. That mask you use may not be helping, for those reasons. I remember going into a local grocery store a few years ago and they graciously had free masks at the door. The problem is they were not individually wrapped so everyone picks up the pile, takes one and puts the rest back down. (Hello!) I may or may not have gotten infected but every test I've had has been negative. (Testing is a whole nother conversation 🙄).  But also various people (vaxed or not, masks or not) have had various results with this so who really knows. But we try to be careful whenever we go out. 

[The-Inside-Cabin]

I found this graphic interesting as it shows the risk associated with different types of masks and different exposure times.   Source HERE

 

[Florida_gal_50]

Yes it goes without saying I wash my hands a ton, did before the pandemic.  I don’t touch my mask with dirty hands nor do I wear it on my chin 🤮.  I don’t keep it in a dirty pocket either or use it 50 times.

[syesmar]

I’m curious about current indoor air quality, too.

Among those who mask but still got it onboard, removing a mask for public dining seems to be a factor.

I know there have been changes to mask policies among crew fleet-wide. Do they wear masks when cleaning staterooms? When I resume cruising I would need to let in fresh air anytime someone else had been in the room.

 

Edited December 13, 2022 by syesmar

[REOVA]

17 minutes ago, syesmar said:

I’m curious about current indoor air quality, too.

Among those who mask but still got it onboard, removing a mask for public dining seems to be a factor.

I know there have been changes to mask policies among crew fleet-wide. Do they wear masks when cleaning staterooms? When I resume cruising I would need to let in fresh air anytime someone else had been in the room.

 

Crew only wear mask if mandated by the ship or personal preference. In July they had to wear them on our cruise. In November they did not, however more crew began wearing them mid cruise (and Captain reminded passengers to call medical if feeling sick) but no mention of uptick in infection or mask requirements. (Wink wink). 

[Heartgrove]

So many times people who contract COVID blame the ship when they most likely carried it onboard. I remember last year when we did our one Viking cruise how they were not only PCR testing daily but also using proximity trackers as well. On most of those cruises, ours included, (described on the VO forum) the 3-4 day PCR test would be when people tested positive. That would have been too soon for contracting onboard the ship.

 

Thankfully it has become a mild infection for most as long as you have been vaccinated  and boosted. That was all it was for me this year and a notch above being asymtomatic. Three Rapid tests with negative results but a confirmed infection using a PCR test.

[Mary229]

I don’t see how they could possible isolate air for each room.  That would require a major engineering renovation.   They do use filters both HEPA and  ultraviolet and possibly others.    I have found the air quality much improved.   The mold control surpasses any I have experienced in the past . I am very sensitive to mold and haven’t had a sniffle this year on any of my cruises except one river cruise

Edited December 13, 2022 by Mary229

[whogo]

43 minutes ago, Mary229 said:

I don’t see how they could possible isolate air for each room.

Nor do I. I hoped that someone would find out about actual engineering changes made to the ship during an "Ask the Captain" session.

 

Holland America said, "Where feasible, we utilize enhanced filters and other technologies to mitigate risk." My assumption is that they find changes to be infeasible more often than not. Perhaps they have made no changes at all to a number of their ships.

 

I hesitated to book our August Zaandam cruise out of concern for covid, continued to wear a mask as I had been doing around town, was uncomfortable around crowds of unmasked people in planes, airports, tenders, and queues and I stayed out of elevators and theaters. I am now hesitate to book a January cruise because of covid, RSV and flu. Hospitals are filling up. A local parochial school reported 92 out of 300 students absent. I do not want to spend my cruise isolated in a cabin and I do not want to infect others.

[Steirisch]

That is good to hear @Mary229.  I've been concerned about the ventilation system before we booked, but the HAL website said they improved their air filtration, so I didn't feel any qualms about booking.

Glad you found the air quality improved.  

Edited December 13, 2022 by Steirisch

[chengkp75]

15 hours ago, The-Inside-Cabin said:

This story, from the early days explored the possibility of people getting COVID while isolated in their cabins.

The article and study you quote from the Diamond Princess is flawed in my opinion, in that they did not actually study the HVAC system of the ship, but just said, "well they only use 30% fresh air, so everything else must be co-mingled in the recirculation".  This is completely false.

 

2 hours ago, Mary229 said:

I don’t see how they could possible isolate air for each room.  That would require a major engineering renovation.

Bingo, miles of new ducting, etc.

 

Use of improved filters, and UV sterilizers can help with overall air quality, but have not been shown to mitigate Covid in any way, as the ASHRAE (American Society of Heating, Refrigeration, and Air Conditioning Engineers) have stated.  The only improved filters that would help mitigate covid are the filters in each cabin.

 

I know I've described this many times, both in discussions about balcony doors, and also repeatedly during the pandemic, but I'll describe shipboard HVAC systems again.

 

Cabins:  There are 3 HVAC systems in each cabin.  The first is the one controlled by the cabin thermostat.  This system is just like a window AC in your house, it takes warm air from the room, and cools it (the fan and cooling coil are either in the bathroom under the vanity or in the "mechanical locker" where they work on your blocked toilet, just outside the cabin), and returns it to the room.  This is the "recirculation".  Note that there is no cross-contamination between cabins, the ductwork only goes from your cabin to the cooler and back to your cabin.  The second system is the fresh air delivery system.  Air exchange is essential, not just to keep the room from feeling "stuffy", but for health reasons as noted in the study of the Diamond Princess.  Fresh air reduces the concentration of a pathogen if present, by diluting it with clean air.  Now, this fresh air supply system takes air from outside the ship, cools it, and delivers it to cabins.  The system does service many cabins (around 30-50, all the cabins on one deck, between sets of fire doors), but the air is one way, from the outside to the cabins, so again, no mixing between cabins.  Addition of this quantity (20-30%) of air to an enclosed cabin will overpressurize the cabin, and this is done for a reason.  The third HVAC system is the bathroom exhaust.  This is designed to take "stale" air away, not just from the bathroom, but from the cabin, in almost the same quantity as the fresh air supply.  This air is also one way, from a bunch of cabins to the outside of the ship, so again, no mixing between cabins.  The bathroom exhaust takes away slightly less air than the fresh air supply brings in, and this keeps the cabin at a slight overpressure, so that air flows out of the cabin under the hallway door.  This keeps smoke in the hallway from entering your cabin in case of a fire, but also, keeps the public air in the passageway from entering your cabin, to prevent mixing of air.

 

Public spaces:  Public spaces use the same types of 3 HVAC systems as cabins:  fresh air supply, recirculation, and exhaust.  However, due to open doors, etc, between public spaces, there is much more mixing of air, and a higher likelihood of pathogens entering the space than your cabin.  Here, a higher percentage of fresh air supply (higher turnover rate), can be very beneficial.  However, I have not seen any study that shows that recirculated air in an HVAC system can carry viable virus from the space, through the ducting, to the cooler, back through the ducting, and into the space again.  What has been shown is that airflow in the space, caused by HVAC supply and exhaust ducts, can spread virus further than just a person to person spread.  But, this is where additional fresh air supply can dilute the possible problems.

 

These systems are the same as before Covid, and are the same as any large building with a central HVAC system, anywhere in the world.

 

As far as I know, there were samples collected from the HVAC louvers in cabins on the Diamond Princess, and showed that there were viruses there days after the people were removed, but this was only done in cabins with a positive case, and the louvers were not identified as to whether they were the cabin recirculation or fresh air louver.

Edited December 13, 2022 by chengkp75

[The-Inside-Cabin]

Thank you @chengkp75 for an in-depth and easy to understand response.   I really appreciate the time you took to put this together!!!!

 

 

[REOVA]

@chengkp75When we sailed on Zaandam in July we noticed the thermostat cut off (light out) after 10 pm and didn't come back on before 6 am. Even if we tried adjusting the temperature. We thought maybe ship was trying to conserve energy. Any thoughts on why they do this? 

[chengkp75]

3 minutes ago, REOVA said:

@chengkp75When we sailed on Zaandam in July we noticed the thermostat cut off (light out) after 10 pm and didn't come back on before 6 am. Even if we tried adjusting the temperature. We thought maybe ship was trying to conserve energy. Any thoughts on why they do this? 

I don't have any idea, never heard of this before. Was the room warm at night?

[Mary229]

9 minutes ago, REOVA said:

@chengkp75When we sailed on Zaandam in July we noticed the thermostat cut off (light out) after 10 pm and didn't come back on before 6 am. Even if we tried adjusting the temperature. We thought maybe ship was trying to conserve energy. Any thoughts on why they do this? 

We had that issue this summer, the air conditioning cut off.  I complained and it stopped happening but for a few nights I thought I was losing my mind.  Again on the Zaandam, 6th deck. 

[ShipWalker]

3 hours ago, chengkp75 said:

...The third HVAC system is the bathroom exhaust.  This is designed to take "stale" air away, not just from the bathroom, but from the cabin, in almost the same quantity as the fresh air supply.  This air is also one way, from a bunch of cabins to the outside of the ship, so again, no mixing between cabins.  The bathroom exhaust takes away slightly less air than the fresh air supply brings in, and this keeps the cabin at a slight overpressure, so that air flows out of the cabin under the hallway door.  This keeps smoke in the hallway from entering your cabin in case of a fire, but also, keeps the public air in the passageway from entering your cabin, to prevent mixing of air...

 

 

 

HVAC bathroom exhaust working as intended.

[REOVA]

10 minutes ago, chengkp75 said:

I don't have any idea, never heard of this before. Was the room warm at night?

More stagnant than anything. We were in North Atlantic (VoV) so heat wasn't an issue. It would turn back on same time in the mornings like the ship was turning off system while we slept. Surprisingly others had the same issue. My DW noticed it (of course) and initially I thought she was wrong (my mistake). 

[chengkp75]

7 minutes ago, REOVA said:

More stagnant than anything. We were in North Atlantic (VoV) so heat wasn't an issue. It would turn back on same time in the mornings like the ship was turning off system while we slept. Surprisingly others had the same issue. My DW noticed it (of course) and initially I thought she was wrong (my mistake). 

I'm wondering if they were doing maintenance to the fresh air supply systems, like coil cleaning.

[AFNavigator]

4 hours ago, chengkp75 said:

The article and study you quote from the Diamond Princess is flawed in my opinion, in that they did not actually study the HVAC system of the ship, but just said, "well they only use 30% fresh air, so everything else must be co-mingled in the recirculation".  This is completely false.

 

Bingo, miles of new ducting, etc.

 

Use of improved filters, and UV sterilizers can help with overall air quality, but have not been shown to mitigate Covid in any way, as the ASHRAE (American Society of Heating, Refrigeration, and Air Conditioning Engineers) have stated.  The only improved filters that would help mitigate covid are the filters in each cabin.

 

I know I've described this many times, both in discussions about balcony doors, and also repeatedly during the pandemic, but I'll describe shipboard HVAC systems again.

 

Cabins:  There are 3 HVAC systems in each cabin.  The first is the one controlled by the cabin thermostat.  This system is just like a window AC in your house, it takes warm air from the room, and cools it (the fan and cooling coil are either in the bathroom under the vanity or in the "mechanical locker" where they work on your blocked toilet, just outside the cabin), and returns it to the room.  This is the "recirculation".  Note that there is no cross-contamination between cabins, the ductwork only goes from your cabin to the cooler and back to your cabin.  The second system is the fresh air delivery system.  Air exchange is essential, not just to keep the room from feeling "stuffy", but for health reasons as noted in the study of the Diamond Princess.  Fresh air reduces the concentration of a pathogen if present, by diluting it with clean air.  Now, this fresh air supply system takes air from outside the ship, cools it, and delivers it to cabins.  The system does service many cabins (around 30-50, all the cabins on one deck, between sets of fire doors), but the air is one way, from the outside to the cabins, so again, no mixing between cabins.  Addition of this quantity (20-30%) of air to an enclosed cabin will overpressurize the cabin, and this is done for a reason.  The third HVAC system is the bathroom exhaust.  This is designed to take "stale" air away, not just from the bathroom, but from the cabin, in almost the same quantity as the fresh air supply.  This air is also one way, from a bunch of cabins to the outside of the ship, so again, no mixing between cabins.  The bathroom exhaust takes away slightly less air than the fresh air supply brings in, and this keeps the cabin at a slight overpressure, so that air flows out of the cabin under the hallway door.  This keeps smoke in the hallway from entering your cabin in case of a fire, but also, keeps the public air in the passageway from entering your cabin, to prevent mixing of air.

 

Public spaces:  Public spaces use the same types of 3 HVAC systems as cabins:  fresh air supply, recirculation, and exhaust.  However, due to open doors, etc, between public spaces, there is much more mixing of air, and a higher likelihood of pathogens entering the space than your cabin.  Here, a higher percentage of fresh air supply (higher turnover rate), can be very beneficial.  However, I have not seen any study that shows that recirculated air in an HVAC system can carry viable virus from the space, through the ducting, to the cooler, back through the ducting, and into the space again.  What has been shown is that airflow in the space, caused by HVAC supply and exhaust ducts, can spread virus further than just a person to person spread.  But, this is where additional fresh air supply can dilute the possible problems.

 

These systems are the same as before Covid, and are the same as any large building with a central HVAC system, anywhere in the world.

 

As far as I know, there were samples collected from the HVAC louvers in cabins on the Diamond Princess, and showed that there were viruses there days after the people were removed, but this was only done in cabins with a positive case, and the louvers were not identified as to whether they were the cabin recirculation or fresh air louver.

Of course, there's also off-ship COVID too.  Everyone blames the ship but did they get off at any ports?  Did they come down with COVID within about 4 days of sailing start...could have been contracted pre-cruise on a flight, cab, hotel, etc.

[Host Jazzbeau]

2 hours ago, ShipWalker said:

 

HVAC bathroom exhaust working as intended.

Good thing the ship's currency is USD.  This test wouldn't work with 1 Euro!  🤣

[wdw1972]

This may be a crazy, radical thought - but it's crossed my mind.  I keep reading (here on Cruise Critic) of people who masked religiously, didn't use elevators, didn't attend shows, washing hands frequently, sometimes wiping down their stateroom, and didn't eat in crowded areas coming down with covid.  Could it be the people have unintentionally damaged their immune systems with all these precautions that they're far more susceptible than those of us who go about enjoying our cruise in a carefree manner as if covid had never happened?  We never wore a mask, didn't hesitate to ride a full elevator, attended shows & musical performances, took shore excursions, ate in restaurants, didn't bother washing hands except for after bathroom use, and didn't use hand sanitizers or wipe down surfaces - none of us got covid (or anything else).  It's starting to look funny to me that the ones who report getting it are the ones going to such extremes to avoid it.

 

Sue/WDW1972

[Mary229]

4 minutes ago, wdw1972 said:

This may be a crazy, radical thought - but it's crossed my mind.  I keep reading (here on Cruise Critic) of people who masked religiously, didn't use elevators, didn't attend shows, washing hands frequently, sometimes wiping down their stateroom, and didn't eat in crowded areas coming down with covid.  Could it be the people have unintentionally damaged their immune systems with all these precautions that they're far more susceptible than those of us who go about enjoying our cruise in a carefree manner as if covid had never happened?  We never wore a mask, didn't hesitate to ride a full elevator, attended shows & musical performances, took shore excursions, ate in restaurants, didn't bother washing hands except for after bathroom use, and didn't use hand sanitizers or wipe down surfaces - none of us got covid (or anything else).  It's starting to look funny to me that the ones who report getting it are the ones going to such extremes to avoid it.

 

Sue/WDW1972

There is truth in that but there are also people who are hyper vigilant because they have compromised immune systems due to illness, medications or age.  

[whogo]

4 hours ago, ShipWalker said:

 

HVAC bathroom exhaust working as intended.

I thought I was the only one to check air flow in hotel and cruise ship bathrooms. I use a piece of toilet paper, I'm not about to risk a dollar bill.

[liketraveling]

41 minutes ago, wdw1972 said:

This may be a crazy, radical thought - but it's crossed my mind.  I keep reading (here on Cruise Critic) of people who masked religiously, didn't use elevators, didn't attend shows, washing hands frequently, sometimes wiping down their stateroom, and didn't eat in crowded areas coming down with covid.  Could it be the people have unintentionally damaged their immune systems with all these precautions that they're far more susceptible than those of us who go about enjoying our cruise in a carefree manner as if covid had never happened?  We never wore a mask, didn't hesitate to ride a full elevator, attended shows & musical performances, took shore excursions, ate in restaurants, didn't bother washing hands except for after bathroom use, and didn't use hand sanitizers or wipe down surfaces - none of us got covid (or anything else).  It's starting to look funny to me that the ones who report getting it are the ones going to such extremes to avoid it.

 

Sue/WDW1972

I am sure allot of cases go unreported. My dad got it last month on a cruise and two days later I got it.   We both had mild cases because we had been double vaxed and triple boosted,  when we got out of isolation, we were afraid to go anywhere because all the hacking and one lady was blowing her head full of snot in the lido at the dinner table.  It could have been flu too.  I am sure there were allot of cases not reported.  If you go on a cruise you need to go that there is a possibility you could get Covid.  Just as a possibility of some other bug out there.  For me I have just decided I won’t cruise anymore.