What is Microbial Contamination?
What is Microbial Contamination? Where does mold come from? Is microbial contamination a health concern issue? How do you properly get rid of a microbial contamination?
Microbial contamination refers to a variety of microorganisms, including mold, bacteria, viruses and protozoa; and fungi, which includes molds, yeasts, and their by products and toxins. All of these can affect the health of a building and its occupants.
As a starting point the proper job sequencing for a typical microbial-remediation project includes but it not limited to: identifying and stopping the source of moisture; setting up containment; establishing negative air; removing contaminated building materials; cleaning surfaces; drying the affected areas; conducting a post remediation evaluation.
Mold spores are a major concern for our project managers. Because of their very small size, mold spores can be anywhere there is air, including under carpet, inside wall cavities, under kitchen cabinets, virtually everywhere. Molds are usually not a problem unless mold spores land on a damp spot and begin growing. They digest whatever organic material they grow on in order to survive. Some molds grow on wood, paper, carpet, foods and insulation, while other molds feast on the everyday dust and dirt that gather in the moist regions of a building. Generally mold spores are hydrophobic. This means that spores do not like water itself. While mold spores need water to colonize (germinate and grow), they like wet organic substances, not a puddle of standing water.
Two Drying Methods
After making the decision of whether or not to dry a material, Project managers begin evaluating how to begin the restoration work. Many methods are available - each applying a different combination of humidity control, temperature, airflow and physical manipulation of the material (e.g., injection of airflow, perforation, removing finish materials).
Our Project Managers use the information obtained during evaluation of materials to help select the best drying method for the job. Generally there are two primary methods to promote drying of affected structures: 1) disruptive methods and 2) aggressive methods.
Disruptive Drying Methods
Disruptive drying methods involve removing wet items, injecting air to speed drying, or perforating surfaces to allow water to evaporate. The term disruptive is used because repairs will have to be done after the structure has been dried. Use disruptive methods when contamination, damage, cost or customer concerns require removal or manipulation of the affected material.
Aggressive Drying Methods
Aggressive or "in-place" drying methods involve leaving wet items in the structure and drying them in-place using warm, dry direct airflow. Aggressive methods are used when contamination and damage are not concerns, and when it is cost effective to dry an item instead of replacing it.
Project Managers will use aggressive drying methods when all of the following are true:
- The water intrusion came from a sanitary source (Category 1).
- Drying carpet and underlay (pad, cushion) in place will not cause structural damage to subfloor (especially hardwood).
- Adequate dehumidification is available and usable on site.
- Deep extraction tools are available.
The success of each decision made during the restorative drying process depends on the information upon which the decision was based. A skilled technician with quality meters will make the proper decision at each phase of the project.
Removing Moisture from Materials
The rate at which moisture moves through materials depends upon two primary factors: the type of material affected and the degree of wetness. The type of material affected will vary in permeability (ability for water to pass through the material), hygroscopicity (ability to absorb water), thickness, density, temperature and "R" factor (resistance to heat transfer).
Each of these characteristics will influence the way in which water travel through the material. The degree of wetness will influence the moisture movement, in combination with other material characteristics, by indicating the type of water being addressed. Water will be present in one, two or three forms:
- Surface Water
- Free Water
- Bound Water
Surface water is readily available at the surface of a material. It is liquid, visible and will evaporate readily. All materials are capable of supporting surface water. Surface water is best removed physically using mechanical extraction equipment or other physical means. Minute amounts of remaining surface water are readily evaporated using large amounts of airflow and moderate temperature and humidity.
Free water is present within a material but is not bonded. It exists in cavities, open pores and other air spaces within the material. It is liquid, generally visible by a darkening of the material (e.g., wood) and can evaporate readily. Most materials are capable of supporting (containing) free water. Materials not capable of retaining measurable amounts of free water are non-permeable, non-porous materials such as vinyl, vinyl composite, steel, rubber and some other solid, synthetic materials.
Bound water is absorbed by the material and held captive by chemical bonds. It is similar to vapor in that it is not fluid, yet similar to a solid/liquid in that it is bonded to other molecules. Because it is bound to other molecules, it must first be freed before it can be removed.
Hazard Awareness and Risk Assessment
The first line of defense against safety hazards is awareness. A hazard inspection checks for any work-site situation that potentially poses danger to life or property. Project managers must then perform a risk assessment on all potential hazards found on the work site. The assessment evaluates the risk or likelihood a particular hazard will cause harm. Due to the unsafe nature of most water damaged structures, hazard inspections and risk assessments are essential for protecting workers.
The initial hazard inspection and risk assessment of a water damaged facility would involve three important aspects. The first step is to identify hazards that could give reason not to enter the building, such as wet electrical panels and collapsing ceilings. The second step is to identify the presence of regulated building materials such as asbestos, lead or PCB's (polychlorinated biphenyls). Government-regulated substances may require testing or inspection services from specialized. Third-party experts to assess health and safety issues. Finally, a competent technician conducts a risk assessment and installs or implements the necessary hazard controls for any identified hazards.
HVAC Systems: Affected by a Fire
HVAC systems condition the air within occupied interior spaces. They ventilate and supply warm or cool air through an air conveyance systems referred to as ductwork. HVAC systems typically have a cold side, or return air, and a hot side, the supply air. An air filter system is normally strategically located on the return side, somewhere before the blower motor compartment. Most air filters are engineered to capture smaller airborne contaminants in order to protect the blower compartment components.
Although HVAC systems all have the same purpose, they vary greatly in design. Soot and smoke odor removal is relatively easy in some types, especially metal ducts. However, following a structural fire, soot contaminates coat most interior fiberglass surfaces. Fiberglass duct insulation is easily contaminated due to the volume of air spaces within the insulation matting. When ducting becomes exposed to smoke odor gases and particulates, PICs penetrate deep within the fiberglass fibers used to insulate the ducting. An HVAC system that was operating during a fire will certainly be more heavily contaminated than one that was turned off;however, systems become contaminated even when they were not operating during the fire.
An inspection of the HVAC system will determine when the complete system requires cleaning. In heavy soot contamination situations, restorable mechanical components within the HVAC system should be disassembled, cleaned and deodorized in accordance with published NADCA standards. NADCA stand for National Air Duct Cleaners Association.
Installation of Air Movers
Air Movers specifically placed to ensure proper circulation of air throughout the affected area.
Air movers are placed in the environment to ensure rapid evaporation across all affected surfaces. The number of air movers necessary depends upon the number of wet surfaces, the amount of water present, and the ability for air to reach each wet material (e.g., wall cavities, behind cabinets, and under contents).
The IICRC S500 Standard recommends that air mover installation quantities should be based on the amount of wet surface area in affected spaces. For the initial phases of drying, air movers should produce continuous airflow across affected material surfaces. A step-by-step process for determining the proper number of air movers is:
- Place one air mover for each affected area.
- Add one air mover for every 50 to 70 sqft. of affected floor area.
- Add one air mover for every 100 to 150 sqft. of affected wall surfaces (above 2') and ceiling surfaces.
- Add one air mover for every room offset or inset greater than 18 inches.
This calculation should provide an appropriate amount of air movement for most water intrusions, but can vary depending of the situation and type of materials affected.
Once the number of air movers to be installed has been determined, several factors will influence their actual placement. These factors include: the type of material affected, the degree of saturation, the accessibility of the actual wet surface, power availability and equipment availability. Below are some general guidelines for installation of air movers:
- Air movers are directed toward the wall at a 5 to 45 degree angle, depending on the type of air mover.
- The air mover's snout will almost touch the wall, within in 1 to 2 inches.
- All air movers in each area will face the same direction to ensure that air movers are not pushing against each other.
- When placing air movers, we need to consider the need for circulation throughout the affected area.
- Specialty air movers may be necessary if building cavities require air flow.
Board-Up: Securing your home or business
Fitted insert board-up
If doors or windows have been damaged or destroyed in a fire, rain and wind may enter the building and cause further damage. Also, curious onlookers or vandals may attempt to enter a damaged building. To help prevent these problems, it may be necessary to "board-up" the property.
The board-up procedures should provide durable protection for the damaged structure and cause minimal additional damage to building surfaces. Board-up methods include:
- Fitted inserts
- Bolt tension
- Tarps and shrink wrap systems
The cover-over system is easy to install and probably most applicable on roofs. Large expanses of roof can be covered quickly with heavy-duty tarps. Fitted insert board-ups are more difficult to install but are more weather tight than the cover-over system.
Bolt tension methods are relatively easy to install and have the advantage of being weather resistant and difficult for intruders to disengage. Placing carpet or carpet pad on the interior brace will prevent additional damage to wall surfaces.
Mitigation services help prevent additional damages. Loss mitigation services include winterization to prevent freezing, controlling corrosion, and cleaning surfaces to prevent staining.
As soot combines with atmospheric water vapor, it becomes acidic. Neutralization of acid smoke residue is a fundamental part of the initial stages of corrosion prevention. In most cases, alkaline solutions are used to help remove and neutralize the acid smoke residue.
After removing the smoke residue from metallic and plastic laminate surfaces, apply an oil-based coating (Many restoration professionals use a common lubricant like WD-40). This treatment will slow down and/or inhibit corrosion and discoloration by airborne smoke particles that remain after the Project Manger completes the emergency service visit. This simple, but often overlooked, step can help to reduce overall replacement costs.
Bomb Cyclone hitting the Midwest
Weather Radar showing the Bomb Cyclone over the Midwest Region.
In early March 2019, we experienced a winter storm that is know as a "Bomb Cyclone", but what is a Bomb Cyclone?
It is an intense and ferocious winter storm, and occurs when there is a rapid pressure drop, falling at least 24 millibars (which measure atmospheric pressure) over 24 hours, know as bombogenesis. This type of winter storm is expected to bring hurricane-force wind gusts, possible blizzard conditions and a flood threat across the Midwest.
The storm's heavy rainfall has caused major flooding and damaged many roads and bridges in Iowa, Nebraska, and Missouri. Numerous creeks and streams were out of their banks and caused widespread flooding. If your home or business is damaged due to flooding, call your trusted advisors at SERVPRO West Kirkwood/Sunset Hills today!
River Flooding Update
River Flooding Updated Map
The St. Louis area has experienced two major floods over the past few years resulting in a ton of damage to homes and businesses in the area. SERVPRO of West Kirkwood/Sunset Hills is here to help with any damages that occur to your home or business.
Flooding can affect your home or business in multiple different ways. Heavy rain can cause a number of different issues for home and business owners in the St Louis area. It can cause over land flooding, hydrostatic pressure, over charged sewer lines and a number of other issues.
Keep up to date on how heavy rains and flooding can impact the Kirkwood and Sunset Hills areas. Check out the River Flooding Update Map to see what is going on in your area. If you are experiencing flood damage in your home or business, call your trusted advisors at SERVPRO of West Kirkwood/Sunset Hills!