Health Effects of Boat Mold (and keeping your boat mold free)

[Sully]

This is part II of the post on mold in boats. Here we will see what some of the health effects from mold are as well as how to keep mold from growing in the first place.

HEALTH EFFECTS:

Mold is around us at all times, in small quantities. The spores are everywhere. Colonies of mold grow once spores find the proper growing conditions. The spores themselves can last thousands of years, lying dormant, until the conditions are right for growth. How do you know you have problems with mold?

Some of the health effects of mold can be as follows:

*fatigue
*headaches
*fever
*eye irritation
*irritations to the mucous membranes of the mouth, nose and throat
*sneezing
*rashes
*coughing
*severe allergic reaction

If you have these symptoms only when aboard your boat, you probably have a mold problem.

I've personally had fatigue, headaches, eye irritation, irritation of mucous membranes, sneezing, rashes and coughing from our mold problems. ALL AT ONCE! This happened when I was cleaning the mold without the proper mask on, so wear your mask to avoid this.

In all honesty, mold itself is one reason we have considered moving onto land. We have been sick on our last boat from it and I felt some symptoms return on this boat after we wintered over. There just isn't enough air circulation when it's cold out and you end up breathing the mold all day - very bad for you. Will it kill me early? I don't know... but probably. I also suffered from a mold-induce asthma on the last boat. It would kick in for seemingly no reason, like lifting up the dinghy on the davits... not even a strenuous activity, but I couldn't breathe at all doing it.

KEEPING MOLD AT BAY (Mold Prevention):

Keeping mold at bay is simple, in theory, but difficult in practice.

Mold needs 3 things to grow:

*Moisture
*Food (wood, paper, cellulose, food, organic matter etc...)
*Cool temperatures

Of course, boats are very damp, full of wood and cellulose and are often cool in lockers or in bilges. This makes for prime mold growth conditions.

Keeping mold from growing involves changing only one of the above items the mold needs to flourish. You can change the moisture, the food (not likely to be easy), or the temperature.

Because our boats are outdoors, we are typically not able to control the temperature of the boat to the degree necessary to stop mold growth, which would require sub freezing temperatures or temperatures hotter than some of the hottest places on Earth. Unfortunately, we have no adequate method of controlling the temperature to prevent all mold growth. It is possible for mold to grow in temperatures between 32 deg F and 95 deg F. However, the best temperatures range (for the mold) is between 77 and 86 degrees F. Coincidentally, this is the same temperature range we find comfortable.

Our boats are made with materials such as wood, carpeting, cushions, etc... These materials provide excellent food for mold growth. Unless you have a boat made entirely of fiberglass (even where you sit in the saloon), you will have some material integral to the boat that supports mold growth. There is essentially no way to change this.

On boats that are in cold environments, parts of the hull become much colder than the warm, humid air you are comfortable in with a heater running. This causes the warm, humid air from your breathing, cooking and dish washing to condense onto the cooler surfaces, essentially "watering" a mold colony like you would water a lawn or garden. Bad news.

These situations leave only one single way for you to control mold growth: Control the humidity and moisture in your boat.

The majority of molds require a moisture level of 70% relative humidity. More often than not, molds end up growing where there is either a leak (from faulty plumbing, leaky hatches or ports, hull-deck joints, cockpit lockers, etc...) or from condensation. If you can keep your relative indoor (boat) humidity below 60%, you will have no mold growth (excepting any condensing surfaces). One way to do this is to keep the boat open to the outdoors on days without fog. This will dry the air out inside the boat.

Sometimes, it is too cold to keep all the hatches and ports open, or it is raining out, or foggy. Then what?

The only thing you can do then is to use the Borax system described in Part One of this article, or use a dehumidifier. Dehumidifiers use a relatively large amount of power and will require a substantial electrical system to support them at anchor. One of the most efficient and smallest dehumidifiers that actually works (note that there are many little products made for boats that aren't up to this task) is the Soleus Air CFM-25. I have one of these dehumidifiers and it has worked well on both boats. Unfortunately, it became contaminated from my last boat's mold problem and (I think) has introduced some of that mold into the new boat. UGH! So... I have to get a new Soleus Air dehumidifier. The unit draws (if I recall) approximately 12-15 amps per hour @ 12VDC.


Soleus Air Dehumidifer

Lastly, there are several things you can do aboard your boat to minimize humidity you create yourself:

*Leave no standing water in sinks or basins.
*Shower elsewhere or on deck using a sun shower
*Do not strain hot pasta water in the galley sink - take it outside
*Fix any and all leaks
*Open hatches and ports any time it's nice and dry out
*Install dorade vents in monohulls
*Run a wood stove or diesel natural draft heater - it continually draws air in from outside through cracks, sucks it up the chimney, heats and dries the interior surfaces
*Run your AC in warmer climates - only at the dock of course, but it will work

I hope this 2 part post/article for the library has helped someone with boat mold problems. I have suffered a lot from it. I'll probably die early from it, unfortunately. Maybe this article can help someone else not have to go through all this. It is a constant battle on boats.

If an members would like to write articles such as this one, please feel free to do so and put them here in our Marine Library section.

Sully

[imagine2frolic]

I had a friend in Ca. nearly die from mold. He kept getting sicker, and sicker. That was one clean boat after he found out what it was......i2f

[Sully]

Originally Posted by imagine2frolic

I had a friend in Ca. nearly die from mold. He kept getting sicker, and sicker. That was one clean boat after he found out what it was......i2f

Yeah, isn't it the strangest thing??

I figured mold was nothing. I had always thought people who complained and were scared of mold were just being hypochondriacs. Until you live in a closed environment without much air and with a lot of mold, you don't understand the potential health problems, which can become fatal.

My boat is just like your friend's... sparkling clean! ha ha

[Felix]

I too know how bad the mold can be. We were living in a camper in Florida during the summer of 2005 when we had a bunch of hurricances come through, tree limb punched through the roof and then water soaked the wood panel on the roof. I patched the hole, but then mold grew in the rotten wood. The tough part was that the symptoms come on slowly, so it takes a while to figure out what the problem is. I was wheezing, coughing, headaches, having trouble breathing all the time. It took getting so bad that I felt good at work, would come home walk inside and within 10 minutes I was weezing and choking. I suffered for months before it got that bad, and I was ready to live in a tent before stepping back inside that toxic site.

Sully, unlike you though, I've never had a problem on a boat, and I'm on my 9th year living aboard my 3rd boat. I think a big part of the problem is where your boat is. We don't do cold.

[Sully]

Originally Posted by Felix

I too know how bad the mold can be. We were living in a camper in Florida during the summer of 2005 when we had a bunch of hurricances come through, tree limb punched through the roof and then water soaked the wood panel on the roof. I patched the hole, but then mold grew in the rotten wood. The tough part was that the symptoms come on slowly, so it takes a while to figure out what the problem is. I was wheezing, coughing, headaches, having trouble breathing all the time. It took getting so bad that I felt good at work, would come home walk inside and within 10 minutes I was weezing and choking. I suffered for months before it got that bad, and I was ready to live in a tent before stepping back inside that toxic site.

Sully, unlike you though, I've never had a problem on a boat, and I'm on my 9th year living aboard my 3rd boat. I think a big part of the problem is where your boat is. We don't do cold.

You're absolutely correct, Felix.

The where is very important. The pink mold that this boat had a little patch of here and there was nothing. Didn't affect me even a little. We didn't get the tough mold until we moved the boat up to the northeast. The darker mold grows best on condensing surfaces in the 40 degree range, from my experience.

I have managed to get rid of it, but still... location, location, location!