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Which Method Will Evaporate The Water Out Of The Pot Faster!

Boiling the Water or Putting it in the oven at 500 degrees?

The Winner?

Boiling the Water!

Boiling The Water

 Then asked, most people assume that the water in the pot on top of the stove would take longer to evaporate, but it doesn’t.  In our tests, it took 22-25 minutes to evaporate the water on the stove top.  Why is this? Because the vapor pressure of the water is higher than the vapor pressure of the air. Basically, in this example, the temperature of the boiling water is higher than the temperature of of the surrounding air, and this causes faster evaporation. 

The Oven Example

Most people assume that, because the temperature in the oven reached 500 degrees, that the water would evaporate faster than on the stovetop. Makes sense, right?  In our tests, the pot of water took 2 hours to evaporate at 500 degrees. How could that be? Because the vapor pressure of the water was close to the vapor pressure of the air.  You see, in this example, the temperate of the air and the temperatures of the water were about equal, causing a similar “vapor pressure.” As a result, the water evaporated slowly.

How Does Evaporation Occur? Now that we know that the vapor pressure of the water was higher than the air and that is what caused the faster evaporation, let’s now understand when evaporation occurs.

In the IICRC S500, Chapter 5, page 122;

“Psychometric by definition” = evaporation occurs if the vapor pressure of the air is lower than the surface vapor pressure of the material.”

So let’s go back to that illustration.  The vapor pressure of the air was lower than the vapor pressure of the boiling water and that is why the evaporation rate was fast.

Now, what is the definition of vapor pressure?

“Vapor Pressure = A measure of a substance’s propensity (a natural inclination or tendency) to evaporate…It increases exponentially with an increase in temperature.” – U.S. Environmental Protection Agency.

What Does All This Mean To A Restorer?

According to the EPA, the ONLY way to increase the vapor pressure exponentially is by adding HEAT.

Have you ever asked yourself “Why does it take 3-5 days to dry out wet structures?  When we are drying a wet structure aren’t the wet materials cooler when it is wet?” YES! So, when we are using in place drying and we have air movers moving the air in a room, the vapor pressure of the wet materials is CLOSE to the vapor pressure of the air. To make it even easier to understand, the temperature of the wet materials is close to the temperature of the ambient air, which means SLOWER evaporation.  That is why it takes 3-5 days to dry out wet structures.

Therefore, if we can get the vapor pressure of the wet materials higher compared to the vapor pressure of the air, the FASTER the evaporation.  In simplistic terms, the higher the temperature of the wet materials compared to the surrounding air, the faster the evaporation rate.

However, if we are just heating the air, the temperature of the wet materials is close to the temperature of the air which means slower evaporation, regardless of the temperature of the materials.  So how do we speed up the evaporation rate in the wet materials? By directing, floating, tenting, or containing the heat to the water.

Doesn’t Heat Naturally Rise?

If we just heat the air like a lot of other heat drying equipment does, where does the heat naturally go? You’re right – the ceiling.  Now, MOST of the flood jobs that restorers do start from the floor, and end about 2 feet up the wall.  The sill plates are the hardest and usually the last parts to dry in a wet structure.     

So, instead of just heating the air and wasting all our BTU’s, we should float, tent, contain or direct heat to the wet materials.  

So if we float the carpet as you see here, where is all the HEAT? Right at the water and when you heat water it evaporates

 Now what does the IICRC say about Heat?12.1.22    & 12.1. 23  (Page 52)  Heat accelerates evaporation, heat should be applied directly to materials

Now the IICRC did NOT say to heat the air, it stated to DIRECT the heat right to the materials and this will accelerate evaporation.
 

12.3.1.1        Partial (or soft) floating of carpet. Carpet acts as an insulator and holds heat close to the materials being dried. (Page 55)

So if floating of carpet was so bad for carpet then why does it say that by soft floating of carpet (we do not want the carpet flapping, this WILL cause delamination) this will act as basically an insulation blanket and keep the heat close to the materials being dried. Therefore, because the vapor pressure of the wet materials is HIGHER than the vapor pressure of the air, this means is that you will create FASTER evaporation or to understand in simplistic terms the temperature of the wet materials is hotter than the surrounding air which will cause faster evaporation.
 
12.3.2.10.4 Drying walls, solid wood floors, the underside of sub floors, etc. can be accelerated by applying heat to the materials.
Here it states that if you again apply HEAT to the materials you will dry faster. Do you notice it didn’t say to use warm air, no it stated to use heat and this will accelerate to evaporation rate.

And The Take Away Is… 

So after all this information we have come to realize that Heat Drying and Direct Heat Drying have two different categories. Now with TES/ETES if you just want to heat the air you can. But, if you can direct, contain, direct or tent the heat – this is what will help you create faster evaporation and then you can dry out wet structures faster.

 The only equipment out there that does all this is TES – the leader in Direct Heat Drying.

There is a CSA Standard for Emergency Response called the Z731. In this Standard it states that in every emergency there is an initial state of confusion and disbelief. When an emergency strikes there may be a time where responders are overwhelmed and cannot deal adequately with the emergency. Through proper preparation and planning the risk, loss and damage can be minimized.
Preparation of an emergency response plan for an apartment building can be divided into three categories: organizational objectives, hazard vulnerabilities and identifying resources.
First off we must be able to organize what the objectives are in an emergency. The objectives usually are preventing injuries or fatalities, preventing damage to property and a return to normal activities.
The plan must identify who is to be called first. The initial responder must have the authority to make decisions, this is especially important over the Christmas Holidays when the ability to contact senior management may not be possible. A list of potentially hazardous situations should be compiled. They usually fall into one of three categories- natural hazards, manmade hazards and technological hazards. For the purposes of this article we will focus on the manmade/natural hazards of water damage and fire and smoke damage. Then a series of safe operating practices should be devised for each one of the potential hazards that may be encountered.
After having compiled your list of potential emergency situations it is fairly evident that the first thing to do in most situations is to call 911. This is what makes water damage so different as an emergency because 911 will not respond to such a call. You must have a list of internal resources who are able to respond such as the phone number of the caretaker/superintendant to turn off the water. These responders must know where the water shut off valves are. Having the number for a plumber familiar with your building also helps. Call the plumbing company you use and see if you can obtain the emergency after hour’s number for the person on call and a secondary number just in case there is no answer. It is Christmas time we are preparing for here, the more numbers the better. Make sure you have the number for a disaster restoration company who offers 24/7 service and be sure its a company you already know responds quickly. When it comes to water damage the faster the response the less damage that will be caused. Have the number for your building’s electrician. Remind people that electricity and water are a potentially fatal mix. Electricians can be extremely difficult people to reach after hours. Have numbers for a second and even third alternative company just in case there are several other buildings being affected by the same situation.
The numbers for all internal and external resources should be readily available to all security personnel. If the building has no on site security then an emergency number should be posted on the call board. It is extremely effective to have these numbers on stickers or magnets and posted in places that they cannot be missed. In Southwestern Ontario you can contact www.dryit.ca.
Once you know who to call and when to call them it is important to devise a list of do’s and don’ts in your buildings.

• In particular identify where the shut off valves are, if there are certain valves that should not be touched mark them as such.
• If there are energy sources that may require locking out then have them identified
• Be sure on site personnel has an idea where the electrical and plumbing conduits are in the building
• Never allow fire stops to be compromised
• Never touch any power sources while you are wet
• Never enter wet electrical rooms
• Be aware of water lines that may have additives that are unsafe to the sanitary sewer system such as roof top heating systems and rust inhibitors in sprinkler systems
• Evaluate the source of the water and if it is potentially pathogenic ensure appropriate engineering controls, safe work practices and personal protective equipment are employed
• Clearly define what mitigating your water damage means in your facility
• Make sure the necessary building blueprints are available to emergency personnel
• Make it clear when an evacuation of the building is required and how the evacuation is to be conducted

The main purpose of this article is to identify the areas of concern during a flood that people who are not normally under the chain of command of the building may be required to make decisions on.
Always remember that the longer it takes to make a decision in a water damage situation the more the water runs, the further it will go and the more damage it will cause.
James (Lee) Senter is the owner of Dryit. Lee is an IICRC Approved Water Damage Remediation Instructor teaching classes across Canada. Lee is an IICRC Master Water Restorer, Master Fire and Smoke Restorer and the Chair of the IICRC Canadian Health and Safety Technician committee. Dryit is a disaster restoration company specializing in dealing with condominiums and office buildings in Southern Ontario. Dryit guarantees one hour response time in regular traffic flow hours. Dryit offers water damage remediation, smoke and fire remediation and mould remediation. Our website is http://www.dryit.ca.