Deodorization Safety Procedures

Safety during Deodorization Procedures

The cleaning and restoration industry is always concerned about safety and health hazards. OSHA—the Occupational Safety and Health Administration—regulates safety in the workplace. Our technicians are OSHA 10 certified. That means that they are trained in the recognition, avoidance, abatement and prevention of safety and health hazards on the job site. There are two methods of deodorization, thermal fogging and ozone, which bring with them significant safety issues. Both methods work by putting substances into the air that could be irritating to humans if breathed. Fortunately, when proper precautions have been taken, deodorizing with either method can be performed safely and effectively. 

Safety with Thermal Fogging

Thermal fogging usually dispenses solvent-based deodorants. Heating and combusting the deodorizing product breaks it down into extremely small particles. Safety precautions are needed to prevent an incident. One potential hazard is the flammable nature of deodorizing products used for thermal fogging. Another risk may be physical reactions of people exposed to the fog.

Our technicians post "Thermal Fogging In Progress" signs or warning notices in easy-to-see areas at all points of entry. The sign may state a time limit for people to wait before re-entering the building or treated area. Our technicians will notify the local fire department and the security monitoring company (if the building has a security system) of the thermal fogging operation. The notification will avoid false alarm calls, because the thermal fog looks like smoke, and uninformed third parties may report the smoke to authorities.

Setup Procedures for Safety

SERVPRO technicians complete several setup tasks before starting the thermal fogging procedure. Setup involves extinguishing pilot lights on appliances such as wood stoves, gas logs, fireplaces, gas ranges, water heaters, and furnaces. The fogging agent can reach a flammable point when exposed to an open flame. We will also disconnect any electrical device that could cause a spark. All people and pets must be vacated from the area to be fogged. Our technicians wear personal protective equipment, including a respirator with organic vapor cartridges, goggles, and chemical resistant gloves. Upon completion the treated area will be thoroughly ventilated to remove odors and fumes before people and pets will be allowed back into occupants the treated area. This can be done by opening doors and windows and setting up exhaust fans and/or high velocity air movers to turn over the air in the treated area. Occupants should not re-enter the building until they are given clearance by our project manager.

Safety Precautions for Ozone

Ozone is a toxic gas and therefore it can be hazardous, but when used properly and following all safety precautions this method of deodorization is as safe as other available methods. Ozone will only be applied in unoccupied areas. All people and pets must be vacated from the areas to be ozoned. Ozone Warning signs will be posted at all entries prior to performing ozone deodorizing procedures. Technicians working around ozone wear personal protective equipment including goggles, chemical resistant gloves, and a NIOSH-approved respirator with an organic vapor cartridge. The treated area must be properly ventilated after ozoning is completed. Unlike thermal fogging Ozone dissipates completely within minutes and leaves no residue. Ventilate the treated area for at least 30 minutes after ozoning completion to address any lingering ozone. It is safe to re-enter treated areas 1 (one) hour after the ozone generation has stopped.

Odor Neutralization Equipment

Effective deodorization often requires a combination of multiple deodorization techniques. The same deodorizing product or the same deodorizing process will not solve all odor problems. Some odors will require fogging, some direct spraying, some activated oxygen, etc. The deodorization technician uses a variety of equipment, depending on the odor situation.  

Highlighted below are the various equipment at our technician’s disposal along with a brief description of how and why our technicians would use them.

Pressure Sprayer / Electric Sprayer

Hand pump-up sprayers or powered sprayers can dispense chemicals at about 50 psi (pounds per square inch) of pressure. They are used to spray applications directly onto surfaces being deodorized. The most common applications for direct spraying in smoke deodorization are on heavily charred structural components or on fabrics and carpets. Since direct spraying wets the surface being treated, only use this method in situations where discoloration is unlikely or of no consequence.

Ventilation Box Fan

Ventilation box fans generate airflow of great velocity, from 3,000 to 5,000 cubic feet of air per minute (cfm). Moving large volumes of air is useful for ventilating odors, fumes, and vapors from a structure.  Box fans perform various deodorizing functions. When odors are heavy in a structure, a restorer may use the box fans to flush as much of the odors from the building as possible. After this initial ventilation, the restorer will use other methods to deal with remaining odors. Box fans are commonly used to ventilate a structure after thermal fogging. The air in a structure which has been thermal fogged for deodorization should be exchanged to ensure all vapors and residues of the deodorizing product are removed. Air is exchanged by ventilating indoor air to the outside and drawing outside air into the structure. The box fans help exchange outdoor air for indoor air.

Fogging Equipment

Fogging is a common deodorization process. A deodorizing product is dispensed as extremely small particles in a mist. The fogging process produces particles small enough to penetrate surfaces where odor particles are giving off odor. There are two distinctly different fogging procedures – Dry and Wet Fogging.

Dry Fogging — the Thermal Fogger

Thermal foggers vaporize solvent-based or petroleum-based deodorizers, generating a “smoke” or fog consisting of very small particles. The droplets generated by the thermal fogger range in size from as small as one-half micron to larger particles up to 25 microns, approximating the size of odor molecules. The droplets make a smoke, physically similar to the smoke produced in a fire, enabling the deodorizer to interact more effectively with odor-causing residues. Thermal fogging products are a blend of strong fragrances, odor counteractants, and solvents. They counteract odor-causing residues and eliminate odors rather than just masking them.

Wet Fogging — the ULV Fogger

ULV stands for Ultra Low Volume. The ULV fogger atomizes liquid deodorizing agents, primarily water-based agents, producing a fine mist. These foggers generate deodorant particles of approximately 10 to 60 microns in size, small enough to penetrate into most areas where odor-causing residues accumulate. The ULV fogger dispenses water-based deodorizing products and so is referred to as “wet” fogging and would be used to neutralize “wet” malodors like pet urine.

Oxidation Equipment

Sometimes odor molecules are eliminated by combining them with oxygen molecules. Oxidizing is the process of a substance combining with oxygen. There are two distinctly different oxidizing machines at our technicians’ disposal – An Ozone generator and a Photocatalytic oxidizer.

Ozone Machine

The ozone machine generates ozone, or unstable oxygen molecules (containing three oxygen atoms). Ozone is also known as activated oxygen because it chemically reacts with odor-causing molecules to oxidize residues (become combined chemically with the extra oxygen molecules) and remove the odors. The portable ozone machine eliminates a variety of odors caused by animals, cigarette smoke, mold and mildew, or fire and water damages. Ozone can be toxic to. All people, pets, and live plants should vacate the environment during ozoning. {NOTE: I will share ozone safety procedures in my next blog, “Safety during Deodorization Procedures”}

Photocatalytic Oxidizer

This machine is called a photocatalytic oxidizer. Inside the machine is an Ultraviolet (UV) bulb coated with titanium dioxide. The machine produces Hydroxyl Radicals. A radical is a group of atoms, and a Hydroxyl Radical is a group with an oxygen atom and hydrogen atom (the symbol is *OH).

The photocatalytic oxidizer machine oxidizes odors like ozone, but the process is safer for occupied structures. Deodorizing with the photocatalytic oxidizer does not fill a room like ozone machines do. Deodorization takes place inside the machine.

Air Scrubber

An air scrubber can remove airborne particles, as well as odors and gases, from the air. The device draws dirty indoor air into the machine, then pulls the air through a series of filters, capturing particles, gases, and odors on the filters, and then exhausts clean air back into the environment. The machine holds different types of filters:

• HEPA filters capture tiny, extremely small particles—as small as .3 microns. 
• The activated carbon and potassium permanganate filter removes a wide range of gases and odors by attracting odor molecules to the filter through adsorption.

Injection

Neutralizing agents are injected into a material using a syringe and a needle or a pump and needle. The injection technique is used when the affected area is small or the surface area is delicate. Also, when the surface material cannot be removed for proper application of neutralizing agents the injection technique may be utilized. An example of when the injection method might be considered is when the procedure of detaching carpet from the tack strip and rolling the carpet back is not practical.

In many deodorizing situations our technicians use multiple procedures to produce the desired results. Combining multiple techniques can produce effective deodorization, but you do not always need to use multiple techniques.  As previously mentioned the universal first step of any odor situation is to remove the source causing the odor. The second basic step is to clean the area of residues. After completing these first steps, our technician may find that the malodor has been properly neutralized and that no additional steps need to be performed. Regardless of the severity of the situation, our clients may rest assured that all necessary steps, and only those steps that are necessary, will be taken to ensure proper malodor neutralization.

Next week I touch on important odor remediation safety equipment and procedures.

Odor Neutralization Agents And Techniques

As we have discussed previously there are many kinds and types of malodors. As such, there are many types of neutralizing agents and techniques to use to counteract malodors – each of which affect malodors in different ways.

Here is a list of various deodorants and deodorizing actions;

• Masking agents
• Pairing agents
• Filtration agents
• Disinfectants and sanitizers
• Enzymes
• Air purification
• Oxidation

Masking Agents

Masking agents are not a primary deodorizer for a real odor situation because they do not eliminate odors. Instead, masking agents cover malodors with a more pleasant odor. Usually masking agents are packed in a time-release form, such as beads, wicks, gels, blocks, or solid cakes, so they generate pleasant-smelling vapors for long periods of time. This slow release of deodorant vapors makes masking agents a good weapon against imaginary odors.

Pairing Agents

Pairing agents are chemicals that combine with (or pair with) odor particles. Most deodorants used for fire restoration contain both masking agents and pairing agents. Two different types of pairing agents affect odor particles in different ways:

• Humectant — A highly absorptive material that combines with airborne odor particles and causes them to precipitate onto surfaces where they can be cleaned up. Wet fogging uses this process.
• Counteractant — A neutralizer that combines chemically with odor particles and changes the chemical properties of the odor molecule or destroys odor-causing bacteria. Thermal fogging works in this manner.

Filtration Agents

Filtration agents collect odors in one of two ways - Absorption or Adsorption.

• Absorption agents primarily absorb moisture and odors into the deodorizing agent. This absorbing action occurs when baking soda is placed in a refrigerator to pick up odors. One type of absorption agent is a powder composed of highly absorptive compounds, inert fillers, and perfume. These powders are not very effective because they mostly absorb humidity and oils and do not attack the real odor problem. They are sprinkled on carpets, but can build up in carpets and damage fibers.
• Adsorption agents work by capturing odor gases from the air and holding them on the surface of the agent. These processes are used to filter odor gases from air passing by or through the filtration agent. Activated charcoal is a type of adsorption agent often used in air filtration systems.

Disinfectants and Sanitizers

Growing bacteria and fungi create odors by producing gases. Disinfecting or killing these odor- causing organisms is a form of deodorization. Some chemicals are classified as disinfectants or sanitizers. In the restoration industry these terms have specific technical meanings:

• Disinfectants are stronger than sanitizers.
• The suffix – "stat" means “to control or limit.” A fungistat controls the growth of fungi such as molds.
• The suffix – "cide" means “to kill.” A fungicide stops the growth of fungi, killing the organism.

Some common disinfectants are pine oil, alcohol, bleach, phenolic disinfectants, and quaternary ammonia solutions. These agents are usually combined with a pleasant fragrance. The disinfectants kill the odor causing bacteria and fungi and the fragrance handles the psychological odors.

Enzyme Digesters

Enzyme digesters work effectively on organic or protein materials. Unlike chemical deodorizers, enzymes break down organic odor molecules into substances without odor. The enzyme deodorizer breaks down odor molecules into carbon dioxide (CO2), water (H2O), and water soluble by-products, and these substances dissipate rapidly into the air. The odor is “eradicated.” Enzymes also break down insoluble protein molecules into simple, soluble substances, which can be absorbed by the bacteria and digested.

Air Purification

Purifying the air is a means of removing odors from indoor air.

•  Electronic filters use an electrically charged grid to kill airborne microorganisms as they pass through the filter.
•  Air scrubbers pull air through charcoal filters, capturing odors onto a filter and recirculating the filtered air back into the indoor environment.
•  Ventilation fans exchange indoor and outdoor air, exhausting odors outside and drawing fresh air indoors from outside.

Oxidation

Oxidation occurs when a substance combines with oxygen. Ozone generators produce ozone gas (O3), which permanently destroys odor through an oxidation process. Ozone gas is an unstable oxygen molecule composed of three oxygen atoms. When this unstable molecule comes in contact with an odor particle, the extra oxygen atom combines with the odor particle and oxidizes it. There are, unfortunately, safety concerns to consider prior to performing any oxidation procedure. Like most “chemical” products, ozone can be hazardous, but if used properly this method of deodorization is as safe as other available methods. Safety precautions must be taken when deodorizing with ozone. Use activated oxygen only in unoccupied areas. Ozone is toxic when high concentrations are inhaled, so remove all people and pets from the areas to be ozoned. Ozone Warning signs should be placed at all entries prior to performing activated oxygen procedures. Only certified technicians should enter the oxidized area until it has been determined to be safe by the technician. 

Next week I will share with you the various types of equipment our technicians have at their disposal.

Odor Remediation - Deodorization Procedures

Successful deodorization requires neutralization all odor particles. Deodorization is an integral part of restoration and requires professionals trained in all facets of restoration and odor neutralization procedures. Deodorization would be simple if all odors came from one source and one deodorization method could eliminate all of them. Unfortunately, all odors do not come from one source. Restoration professionals deal with some unique odor problems— things you have never heard of or dealt with before. The odor control technician needs to employ multiple methods of deodorization to deal with the many, various odors.

There are four basic deodorization procedures which must be followed.

1. Remove the source of the odor.  
2. Clean surfaces with odor-causing residues on them.
3. Recreate the conditions that caused odor penetration.
4. Seal surfaces exposed to malodors.

Remove the Odor Source

Simply attempting to deodorize the source with a masking agent will help to cover up any unwanted odors, however, that is all masking agents will do. For example, if the source of odor is a dead animal in a crawl space, you would not think of leaving the animal in place and trying to deodorize by spraying, fogging, or cleaning. In the same way, in a building that is damaged by a fire, you should remove charred structural materials before deodorizing. Debris that is contaminated with smoke residues can continue to give off smoke odors or soils if not removed. The universal first step in deodorization is to identify the source of the odor and remove the source. Taking this initial step will help lessen the amount of odor in the building. Other procedures will be needed, of course, to get rid of all the odors.

Clean Surfaces

Clean surfaces that have odor-causing residues on them. Small particles of odor-producing residue will continue to generate odors if not cleaned effectively. For example, in a grease fire you may need to clean significant concentrations of residue from the stove, countertops, vent hood, vent filter, cabinets, walls, ceilings, etc., to stop odor problems. Check all rooms— not just the kitchen —

to see how far odors have penetrated. Sometimes the entire structure and its contents may need to be cleaned to remove smoke odors.

Recreate the Conditions

No, we are not attempting to "recreate" the conditions that caused the unwanted odor. What we are referring to is the importance of how the neutralizing agent is applied. In other words, to be effective, deodorizers must be applied to the affected surface in a manner similar to the way the odor-causing substances penetrated that surface. For example, if smoke created the problem, a deodorizing “smoke” or fog will be most effective in following odors to their source. If urine contaminated an area, then “flood” affected areas with deodorizers (sanitizers, neutralizers, and digesters).

Also, odors can be distributed in more than one way. For example, decaying flesh produces fumes and gases, which are distributed on air currents to surfaces not in direct contact with the source. This situation may require multiple methods of deodorization. Directly saturate any areas that were physically contacted by the source. Fog other areas to seek out odor vapors that have penetrated surfaces.

Seal Surfaces

The final step of the deodorization process is to properly seal the surfaces that have been exposed to malodors. This step is not required in all circumstances, but may be called for in severe situations. If odor removal would be too expensive or impractical, sealing might eliminate the problem. Two common sealing situations are painting walls and sealing inaccessible duct surfaces in air handling systems.

Next week I will touch on the many types of neutralizing agents and the different effects each have on malodors.