Ask the Experts: Odor Mitigation Tips


Recently, we at Cleanfax hosted an odor mitigation webinar sponsored by IOTG featuring industry experts Mark Cornelius and Cara Driscoll. However, as with any great webinar, time ran out and so many more questions remained to be answered by the highly engaged attendees. Knowing this, we saved every question and had these experts answer them after the fact to help odor mitigation companies and contractors find the answers they are desperately looking for. Without further ado, here are the expert tips and tricks that came from this diverting conversation for leaders and contractors alike to use to their benefit moving forward.

  • Jason Goh asked, “How do you remove the carbon odor build up after fires on the premises?”¬Ě

Mark Cornelius: ¬†Cara did answer this to some degree but we can elaborate further. After the initial “knockdown”¬Ě phase of a fire/smoke project, you are chasing the odor particles down to their gaseous (molecular) form. First, clean the large particulates off of surfaces.

The majority of the products on the market used for the cleaning and restoration industry incorporate chemistry to address the target problem, PIC (Particles of Incomplete Combustion) in this case. Once the surface has been cleaned using a GPC (General Purpose Cleaner), products can be applied that will address the odor a little more specifically.

People have to understand that liquid products can only penetrate so deep into a surface due to the size of the water droplet. This is where gas phase deodorizers (ozone, hydroxyls, Clo2, and the like) come into play. These items address the remaining odors that may have gotten into pores or tough-to-reach areas.

If steps 1-3 are not properly followed it does not matter how much encapsulant or sealers they spray.

Cara Driscoll: I would add or just reiterate that the fastest, most effective way to reduce carbon odor build-up immediately following smoke/fire damage is to ventilate the building and employ AFDs with carbon (charcoal) filters.  

  • Megan Hughes asked, “Is it true that the one thing we as cleaners and restorers can’t guarantee is odor removal?”¬Ě ¬†

Mark Cornelius: Cara said that she never guarantees anything when it comes to an odor. To expound on this question a bit, I understand where Cara and Megan are coming from, however, in my opinion as long as I know I can get to the source of the problem, I can guarantee that certain odors will be gone. With that said, I will give provisional warranties when it comes to odors.

Cara Driscoll: Odor removal is difficult to guarantee for many, many reasons (i.e. animals continue to urinate in the home after urine removal treatment). ¬† But, this is the case also because psychological odors are impossible to remove, therefore I tread cautiously when “guaranteeing”¬Ě complete odor removal.

  • Paul Wimbert asked, “Can you use aqueous CLO2 for source removal?”¬Ě ¬†

Mark Cornelius: All oxidizers including liquid ones must actually have cleaning capabilities designed for the task at hand. If you have a heavy synthetic PIC residue and you are just using a liquid oxidizer (Bleach, Peroxide, CLO2) with no surfactant that can emulsify the gross contaminate then you are wasting your time.

All an oxidizer can do is oxidize the surface, or crust, blocking the remaining odor molecules from getting into the breathing zone of the occupant. Utilize an appropriate cleaner for the soil then engage a product such as liquid CLO2 for odors that your GPC can’t touch.

If the CLO2 product is formulated with a surfactant that will break down the target soil then an all-in-one cleaner could be appropriate. Keep in mind that even most “1 step cleaner disinfectants”¬Ě state you must first clean the gross contaminates from the surface then reapply the product for proper disinfectant activity.

  • Candido Rosario stated, “Some people have the perception that because something smells like roses or gardens and pine it is cleaned. We should never replace one scent with another.”¬Ě What are your thoughts on that? ¬†

Mark Cornelius: I actually addressed this topic in the webinar a bit. I stated that we as restoration contractors depend on “deodorizers, actually, we often use that word incorrectly, in that most fragrances are re-deodorizers/masking agents.”¬Ě I said that we depend on masking agents from start to finish and that we never stop using them. We never have the ability to ascertain if our “deodorization techniques”¬Ě actually worked or not.

To follow up additionally, the only real benefit to using a “masking agent”¬Ě is to address the psychological odor from the get-go. In reality, we should never use a masking agent, in my professional opinion. The restoration contractor can select respirator cartridges that would allow for organic vapors to be detected while filtering out the bad particulates. The client should not be smelling the bad smell once the contractor has taken possession of the work site because the client should not be in the danger zone.

I know that will never happen in our industry, however, we have to stop using masking products from time to time to ascertain if we are making progress. The only other reason to use a pleasant fragrance is, and I know I definitely said this, “I can not remember who taught my odor control class years ago, however, in the presence of an unidentifiable odor or no odor at all the client will interject the malodor. So in short, use masking agents as sparingly as possible. ”

Cara Driscoll: If someone believes that fresh linen or lemon or pine scents mean something is clean, then I can add those fragrances (like Mark said, masking agents) to my cleaning solutions. During my conversation with the customer, I ask if they prefer a fragrance or no fragrance at all. ¬† Then, I understand and can manage their expectations of “clean.”

  • Julie Ticsay asked, “Do disinfectants have any role in your odor remediation processes?”¬Ě ¬†

Mark Cornelius: If you are cleaning something for an odor then you need to use a cleaner. If you are trying to inactivate, kill, or destroy a microorganism then you use a disinfectant. If you have the odor of mold, then you have mold and need to address the actual problem. I am pretty confident that Cara referenced the S520 talking about how it references source removal and doesn’t even mention using biocides. Additional thoughts: There are some times when a disinfectant could be used for odor control like maybe pet urine or protein issues, but once again, almost every biocide is tested on previously cleaned nonporous surfaces. So let’s get to cleaning and leave the disinfectants for the surfaces they were tested on.

Cara Driscoll: My answer would simply be no. As Mark states, disinfectants are used to kill or inactivate microorganisms after proper cleaning. The basics of odor remediation are source removal and cleaning. I don’t see many instances where a disinfectant would be useful to remediate an odor.

  • Pepper Powell asked, “The industrial plant I clean is 24/7/365, what can I do to help keep odor down, not necessarily eliminate it? My techs are in and out of restrooms 2x a day, what can I teach them to do to help with the odors?”¬Ě ¬† ¬†

Mark Cornelius: Without knowing the cleaning protocols currently in place, it is very difficult to coach on any additional steps. Cara kind of came up with a protocol on the fly for this one. I commented that restrooms are tough to deal with when you have a 30-min clean time. When urine absorbs into items, especially grout lines, we do not really get the ability to perform step 3, recreate conditions/levels of penetration. Cara’s suggestion was to apply the proper products and allow an overnight dwell time.

This is especially tough when this is a 24/365 facility. He and his crews were probably already behind the preverbal eight ball from the get-go. His people are probably not doing anything wrong as it is. His people can apply all the products that they want typically, but they are not touching the source. They can try to apply strong masking agents that will last between cleaning cycles but that will probably attract complaints from the client. Not everyone likes the overwhelming smell of lemon or cherry.

If they could get the client to agree to shut one of the restrooms down for a day or two and Powell’s crew was able to throw everything including the kitchen sink at the problem they might be able to get ahead of the issue. I stress, might be able to. As Cara pointed out, if the urine has made it to any components behind the tile, the smell can continue to come back.

My last comment on this is that even if they get the client to agree to shut down a set of restrooms a couple times a year, they cannot guarantee anything. This is most likely a human behavior issue, not a cleaning technique failure.

Cara Driscoll: Consider increasing or adding additional ventilation and/or the addition of charcoal filters to the air filtration system. Without the ability to truly clean surfaces, maintaining heavily-used restrooms is difficult. Deodorizers can be added to busy restrooms in the form of scented urinal blocks, urinal mats, and toilet deodorizers.

  • What do you do about urine-soaked wood flooring? ¬†

Mark Cornelius: This is probably the easiest one to answer, but the client will not like it. Remove the wood floor, discard the wood floor, address the subfloor, and install a new wood floor after completing steps 1-4 of deodorization and steps 1-4 of cleaning. They will probably have to seal the subfloor.  

  • Can you save a carpet pad that has been contaminated with urine? Or, is it better to just replace it? ¬†

Mark Cornelius: What is the value of the carpet? Is it a brand new carpet and a brand new pet that has only had a couple of accidents, or is it 10-year-old carpet with a previous occupant with a pet?

The problem is carpet underlay is cheap in the cost of carpet. If there are extensive pet spots throughout the room then the spots are much larger than what they can see on the surface. I have never found cleaning the padding to be cost-effective. You are still going to have to reinstall the pad and the carpet as well as address the other issues like the subfloor. Replace it, don’t clean it unless you want complaints later.

Cara Driscoll: For minor urine in carpet pads, one could use flushing and sub-surface extraction tools in an attempt to rinse and remove the urine from the pad. Injecting oxidizers or enzymes into the pad is another option used when the urine can be located and is contained in minor areas. But heavy urine damage requires the removal of the pad. It is an inexpensive piece of the overall project.

  • How do you remove odors from concrete? ¬†

Mark Cornelius: How long has the odor-causing issue been present? I sound like a broken record. Step 1) remove the source, Step 2) Clean the source area, Step 3) recreate conditions/penetration, and Step 4) Seal.

When it comes to concrete, how long has the issue been there? If the problem is pet urine, for example, if the pet has been urinating in the same area for five (5) years, there is no way I can recreate the conditions, unless they want me to move in with them. The likelihood is, as much as I avoid sealers/encapsulation, Step 4 will happen 99% of the time due to the inability to complete Step 3.

If it is a protein decomp odor that has only been a few weeks, you might be able to address it with localized gaseous/liquid oxidizers and heat to open pours. The heat will speed up decomposition of odor molecules and open pores of the concrete allowing products to penetrate deeper. They may still have to incorporate step 4, however.

Cara Driscoll: If odors are deeply set in concrete, use an epoxy sealer after thorough cleaning.

  • When do you know if it is best to discard or clean in a trauma situation? ¬†

Mark Cornelius: You are going to have to consider multiple aspects. This is where economics come in to play. What is the item worth and how much will it be to clean it? Will the cost of cleaning it to the point that the item will be returned in a sanitary condition be worth it or not?

When it comes to the odor aspect, it is no different than any other odor. Once it has been cleaned, it should not smell. If it is a soft good, then once again gaseous/liquid oxidizers can be incorporated.

The restorer will have to have the client involved in determining the actual cost of an item to determine if there is any economics to it. In closing for this question, they should strongly consider taking the TCST course, purchasing the S540, and reading it. In the S540, we discuss the ability to clean porous, semi-porous, and nonporous as well as saturation vs splatter, and transfer of biologicals.

 Cara Driscoll: My only comment on this one, as Mark states: Attend the TCST class, and read the S540. That will answer this question.

With these highly valuable tips, tricks, and expert insights now under your belt, it’s time to implement these strategies into your own odor mitigation company to help both your clients and your profits significantly. Stay tuned for more editions of ‘Ask the Experts’ to come and, until then, feel free to also check out this Cleanfax featured post by Mark Cornelius on restoration business management:

Restoration’s ‘Money Button’ Problem



Cleanfax Staff

Cleanfax provides cleaning and restoration professionals with information designed to help them manage and grow their businesses.

Follow Cleanfax Staff

Related Posts

Share This Article

Join Our Newsletter

Expert Videos

Popular Content


CoreLogic: Spearheading Innovation and Technology in the Restoration Industry


Insurance Restoration Strategies Unlocked: How to Identify & Conquer Top Challenges in the Industry

AI sales

Is AI Going to Be the Death of the Salesperson?

Grow your social media

The Digital Marketing Demystified Series‚ÄĒPart 2: Grow Your Business with Social Media

Digital Marketing - Part 1

The Digital Marketing Demystified Series‚ÄĒPart 1: World Class Email Marketing


As a floor cleaning contractor, which of the following best describes your approach to marketing:

View Results

Loading ... Loading ...