Vinegar use in warm climate ?????

Ross · Apr 19, 2008

Nick, The chemistry at work here would seem to

creat an acidic environment that inhibits mold growth. You could probably achieve this with a spray bottle each time you leave the boat. I think that a search of the canned aerosol anti mildew and fungus products in the household products section of the supermarket will yield a better product. I have been completely pleased with the powered ventilation system on Bietzpadlin. Maryland summers and be just as hot and humid as Florida's and our boat may remain closed up for a month at a time, always during the hottest periods. It always is sweet and clean smelling when we come back. I admit to being anal about ventilation and in the first couple of years we found some lockers that needed some help so I put solar driven fans in those also. Now if some water gets spilled into the bilge, within a week it will have dried. Most of the time my bilge is dusty not wet.

RichH · Apr 19, 2008

A better way that mimics old fashioned 'whitewashing'

Farm, dairy and food industries for centuries used caustics to keep mold and fungus and mold under control. Our ancestors 'whitewashed' just about everything for the same purpose. Whitewashing is a caustic compound that will not permit mold spores, mildew or fungus to grow. Get some strong inorganic *caustic* detergent (sodium silicate, TSP --- dissolve the TSP in water, etc.) and simply spray on the surfaces and let dry. Dont apply to finely painted or varnished surfaces (or bare teak) as it may lift the coatings. Bilge paint, fiberglass, etc. is oK to coat, just dont 'soak' the stuff, just a 'light' fine spray. For cleaning mold mildew, such 'caustics' (including lye based detergents) will dissolve and liquify the fungal cells. Caution: when using strong caustic detergents be sure to wear gloves and goggles .... as caustics will also dissolve your skin, eyeballs, etc. If you cant find any inorganic caustic detergent simply go to a farm supply (Agway, etc.) and buy some old fashioned 'lye soap', put it into a jar with some water and let dissolve ..... then spray on the liquid. Molds and fungus THRIVE in acidic atmospheres .... NO to the vinegar as that will create a slightly acidic atmosphere where molds 'thrive'. If your boat is to be long term stored, to prevent mildew, etc. get some paraformaldehyde crystals, put in plastic trays and quickly leave the boat. The gas from paraformaldehyde will kill the mold, mildew and their spores. Paraformaldehyde is not compatible with human lung tissue, so be sure let the boat air out completely when returning and before you go below.

Ross · Apr 19, 2008

RichH, I use vinegar for pickle making because?

You wrote:"Molds and fungus THRIVE in acidic atmospheres .... NO to the vinegar as that will create a slightly acidic atmosphere where molds 'thrive'."

RichH · Apr 19, 2008

You need a very HIGH concentration of vinegar .....

where the pH is 4 or below. Normal ambient east coast atmosphere is probably 5-6pH, due to acid rain etc. which accelerates mold and mildew growth. In industry (pharmaceutical, biotech) peracetic acid + hydrogen peroxide (MinnCAre, a proprietary cold sterilant) is used to make a total 'kill'. and that degrades down to low levels of acetic acid ... which dont do much. With 5% acetic acid (vinegar) @ 2.5pH, the dilution/diffusion rate will not let you reach such low pH areas that will either stun or kill the organisms. Yes, you get 'some' acetic coming off an open container, but mostly what coming off an open container is WATER (95% of whats in vinegar). So if you need to affect a 'kill' you need LOTS of acetic .... like the concentration thats found inside of a pickle jar. Molds 'thrive' at pH 5-6

Napa Ed · Apr 19, 2008

soda

sodium silicate is a flocculantsodium hydroxide is known as caustic sodasodium carbonate is washing sodakeep caustics away from aluminumtrue trisodium phosphate is hard to come by and the phosphate is food for plant life so could cause slime to grow in your bilgehow about just putting in a vent?

Ross · Apr 19, 2008

Molds thrive at certain moisture levels.

If you keep the substrates too wet or too dry then mold and fungus don't grow. We are not looking for a total kill because we can't maintain a sterile environment in a boat. The best we can hope for is to inhibit the growth. That is best accomplished with ventilation. Removal of existing colonies is another subject. I don't think that anyone would want to occupy an environment in which mold spores can't survive.

Joseph Shirley · Apr 19, 2008

Guys, thanks for the chemistry lesson. It's definitely an area

that I know nothing about. I had chemistry as a required course in college, but I barely passed it (and that was 52 or 53 years ago).We have mold problems here in the Northwest also, because of the almost continuing light rain we live in during the winter. It is colder here though, so I have always fought the problem with on board heaters plus one solar powered inlet vent forward and one exhaust vent aft. What improvement could I make to curb the cold weather mold that develops where air doesn't circulate well enough?Joe S

Ross · Apr 19, 2008

JoeS, consider that mold doesn't grow where there is plenty of air movement.

Otherwise the entire rainforest would look like something recovered from the back of the refrigerator after about 3 months. The space under my Vee berth and above my forward water tanks was starting to get a little growth in the corners so I added a little computer fan to draw air in on one corner and cut and exhaust port on the other corner. Three years later it is still clean. Had the same sort of problems at home, corners of the basement were starting to turn green so I added some fans to keep the air stirred up. The 15 dollar ones from HD last about 4 years. So my advise is just add some more fans.

RichH · Apr 19, 2008

The 'technical' answer is simple.....

for inside mold/mildew, first KILL and *remove* all the internal mold/mildew (in all those inaccessible places where they grow); then, continually filter the air with a 1-2µM *gas retention rated* filter to constantly remove the remaining or newly entering spores. A small HEPA or UPLA filter would do 99% of keeping it under control. The not so technical answer is hygiene.... routinely cleaning all those surfaces will remove the nutrient sources which molds/mildew use as a nutrient source, including the removal of the old dead/killed mold/mildew which become the nutrient source of other species. Paraformaldehyde crystals (the gas that comes from it) will stun the spores. ParaF is somewhat dangerous to use and thus may be hard to find especially on the West Coast. There are somewhat less powerful chemicals available from 'boat chandleries" ... MildewGAZ, etc. Simply put them in a plastic bag when you're ON the boat. I discussed 'whitewashing' in a previous post. as molds and mildews, etc. wont grow on a caustic/basic pH surface, no matter how 'wet' or humid it is.

Ross · Apr 19, 2008

OK Rich, Let's get down to the practical.

What do you do on your boat to control mildew and mold? I am interested in some real world suggestions not some technical hypothetical solution for the laboratory.

RichH · Apr 19, 2008

Simple .....

Clean your boat !!!!!!!!! (Caustic) soap and water on EVERTHING possible ... be anal about it, dont wipe up all the soap leave some on the surfaces. All the cooking puts FOOD particles all over the walls, etc. The dead cells that continually exfoliate from your body, Cat dander, etc. are FOOD for microorganisms. A CLEAN surface wont feed the mold. Spend some time regularly cleaning all the 'undersurfaces' and hidden spaces .... the less mold that is there the less spores it will produce. Filter the air if you can. You have to realize that most mold/mildew species are dangerous /toxic to human tissue, especially lung tissue. Anything thats BLACK growing on a boat is probably very dangerous (stachybatris autra and some species of 'aspergillus' are REAL bad ... easy to identify - they're BLACK). Keep the boat CLEAN .... *ALL* the internal surfaces not just the surfaces you can SEE. I routinely in spring and fall I additionally wipe *all* the surfaces of my boat with a mix of Hydrogen Peroxide and Peracetic acid .... kills EVERYTHING and quickly bio-degrades into something quite harmless ............ 'vinegar'. I also use it to decontaminate my water system. Commercially available as "MinnCare" - quite expensive. ;-)

Ross · Apr 19, 2008

Very good Rich! Three paragraphs of what we should do and one of

what you actually do. Thank you.

Calif. Ted · Apr 19, 2008

Even running a dehumidifier I find that

a container of Stay-Dri (or whatever, see link) in the forepeak and aft cabin collect a surprising amount of moisture and help inhibit mold growth.

John Nantz · Apr 19, 2008

Joseph Shirley: Dehumidifier in Poulsbo

Hi Joseph - we've been using a dehumidifier with auto defrost in Poulsbo now for three seasons and it has worked really well to combat mold and mildew on our 35-footer. It is set up on the galley counter and instead of using the "bucket" that a typcial units comes with, I hooked up a clear plastic hose that runs into the sink. When it runs the built-in fan also works so it blows air around in the cabin. According to one article, mold and mildew pretty much cease to grow when the air is below 50% RH so the first year I had it set at the lowest setting which was 35%RH and that worked fine. I was concerned about the ability to prevent growth in the forepeak of the V-berth, in the aft end of the aft cabin, and in other hard-to-get-to areas on board where there isn't much air circulation but it worked fine. The dehumidifier uses significant less energy, about half to a third, compared to the heaters we had formerly used which were two of those round ones with holes in the top and a 40W golden rod under the engine. The heaters ran 24/7 where as the dehumidifier only runs when it went above the 35%RH set point. Last sprint and this year I bumped the set point up to 40%RH and so far it has worked fine. I haven't compared this years electrical consumption against previous years but I expect that there will be a further savings. I did have the heaters on when there was a real cold snap so the energy consumption comparison included everything.After reading all these posts I'm going to make some changes. While in the fall and spring we wiped things down we did it only with the intent of a spring cleaning and not to combat mold and mildew. This spring, however, I'll approach it from a more or less sterilizing approach. We've been pleased with the results of the dehumidifier and maybe next year I might try bumping the set point up to 45%RH. Given what will be the new cleaning procedures this might work and in the process save even more energy.For what it's worth, we also have a PSS shaft seal and a dry bilge.In the Northwest, "going Green" takes on a different meaning!

Joseph Shirley · Apr 19, 2008

Thanks Guys, from Joe S

I have tried the stay dry and a dehumidifier before but the coils frosted up. Maybe I had it set too low. But Il try it again after a good internal scrub.Joe S

letterman · Apr 19, 2008

Awesome discourse.

I worked in a ten story high rise, circa 1950. They have a problem with mold in the hallways behind the wallpaper located by each bathroom. The live ones, people under 70, who shower daily or more, have the worst walls. I used high concentrations of leach to kill it, and TSP (by accident...it's the best "soap" I know for cleaning things.)Obviously I am no genius, so I really appreciate reading stuff like this. So, the wallpaper paste is (apparently) food for the mold. How can they kill the mold and stop it from coming back (or at least, slow it down)? They fired me but I can relay the info to my ex-partner who is still on the staff. One of the problems with the high moisture content was bubbling of the plaster, which we called a pop-out. I did over 58 in the year I was there (and all they did was bitch about it. Took to long, didn't do my floor first, etc.)

Ross · Apr 19, 2008

Considering dew points, relative humidity, ventilation

and a few other things. I have had such success with keeping my boat free of mold that I have given much thought as to why. first my ventilator fans are solar powered which means they only run when the sun is bright enough the energize the solar panel. This means that the air brought into the boat is warm and dry(sorta). At night the fans don't run so the boat stays warm as the night cools off. This is where dew points come in. When the dew point is 50 degrees the outside of a beverage glass coulder than that will get covered with condensate. If this happened inside a boat you would have a puddle that needed to evaporate or grow mold. So by filling the boat each day with air that is warmer and drier then the air at night the inside of the boat remains dry. On foggy and rainy days the fans don't run and therefore don't pull saturated air into the boat. I have seen days when we have had several very cool days and nights and the walkways on the north side of buildings are damp on a sunny day because the temperature of the pavement is lower than the dew point in the air.

MoonSailer · Apr 19, 2008

ventilation

We had no mold problem at Panama City,FL and Mobile, AL. I made a vented hatchboard and that was it. The boat was always dry and no mold. It gets hot during the day and drys a boat well. This is assuming no water in the bilge and no leaking windows etc. But if your boat has leaks the boat will be wet and humid and mold will grow. Dry is good. Along the gulf coast it is hot during the day and the water is warm at night. Water inside a boat is not from condensation. But with leaks and poor ventilation the inside of a boat can be like a sauna.