Monday, May 29, 2017

Carbon Monoxide Poisoning and Detectors

Carbon monoxide (CO) is a colorless, odorless, poisonous gas that forms from incomplete combustion of fuels, such as natural or liquefied petroleum gas, oil, wood or coal.
 
Facts and Figures
  • 480 U.S. residents died between 2001 and 2003 from non-fire-related carbon-monoxide poisoning.
  • Most CO exposures occur during the winter months, especially in December (including 56 deaths, and 2,157 non-fatal exposures), and in January (including 69 deaths and 2,511 non-fatal exposures). The peak time of day for CO exposure is between 6 and 10 p.m.
  • Many experts believe that CO poisoning statistics understate the problem. Because the symptoms of CO poisoning mimic a range of common health ailments, it is likely that a large number of mild to mid-level exposures are never identified, diagnosed, or accounted for in any way in carbon monoxide statistics.
  • Out of all reported non-fire carbon-monoxide incidents, 89% or almost nine out of 10 of them take place in a home.
Physiology of Carbon Monoxide Poisoning
When CO is inhaled, it displaces the oxygen that would ordinarily bind with hemoglobin, a process the effectively suffocates the body. CO can poison slowly over a period of several hours, even in low concentrations. Sensitive organs, such as the brain, heart and lungs, suffer the most from a lack of oxygen.
High concentrations of carbon monoxide can kill in less than five minutes. At low concentrations, it will require a longer period of time to affect the body. Exceeding the EPA concentration of 9 parts per million (ppm) for more than eight hours may have adverse health affects. The limit of CO exposure for healthy workers, as prescribed by the U.S. Occupational Health and Safety Administration, is 50 ppm.
 
Potential Sources of Carbon Monoxide

Any fuel-burning appliances which are malfunctioning or improperly installed can be a source of CO, such as:
  • furnaces;
  • stoves and ovens;
  • water heaters;Cars should never be left running in a garage
  • dryers; 
  • room and space heaters; 
  • fireplaces and wood stoves;
  • charcoal grills;
  • automobiles;
  • clogged chimneys or flues;
  • space heaters;
  • power tools that run on fuel;
  • gas and charcoal grills;
  • certain types of swimming pool heaters; and 
  • boat engines.
 
 
 
 
PPM
% CO 
in air
Health Effects in Healthy Adults
Source/Comments
0
0%
no effects; this is the normal level in a properly operating heating appliance

35
0.0035%
maximum allowable workplace exposure limit for an eight-hour work shift
The National Institute for Occupational Safety and Health (NIOSH)
50
0.005%
maximum allowable workplace exposure limit for an eight-hour work shift
              OSHA
100
0.01%
slight headache, fatigue, shortness of breath, 
errors in judgment

125
0.0125%

workplace alarm must sound (OSHA)
200
0.02%
headache, fatigue, 
nausea, dizziness

400
0.04%
severe headache, fatigue, nausea, dizziness, confusion; can be life-threatening after three hours of exposure
evacuate area immediately
800
0.08%
convulsions, loss of consciousness;
death within three hours
evacuate area immediately
12,000
1.2%
nearly instant death

 
 
CO Detector Placement

CO detectors can monitor exposure levels, but do not place them:
  • directly above or beside fuel-burning appliances, as appliances may emit a small amount of carbon monoxide upon start-up;
  • within 15 feet of heating and cooking appliances, or in or near very humid areas, such as bathrooms;
  • within 5 feet of kitchen stoves and ovens, or near areas locations where household chemicals and bleach are stored (store such chemicals away from bathrooms and kitchens, whenever possible);
  • in garages, kitchens, furnace rooms, or in any extremely dusty, dirty, humid, or greasy areas;
  • in direct sunlight, or in areas subjected to temperature extremes. These include unconditioned crawlspaces, unfinished attics, un-insulated or poorly insulated ceilings, and porches;
  • in turbulent air near ceiling fans, heat vents, air conditioners, fresh-air returns, or open windows. Blowing air may prevent carbon monoxide from reaching the CO sensors.
Do place CO detectors:
  • within 10 feet of each bedroom door and near all sleeping areas, where it can wake sleepers. The Consumer Product Safety Commission (CPSC) and Underwriters Laboratories (UL) recommend that every home have at least one carbon monoxide detector for each floor of the home, and within hearing range of each sleeping area;
  • on every floor of your home, including the basement (source:  International Association of Fire Chiefs/IAFC);
  • near or over any attached garage. Carbon monoxide detectors are affected by excessive humidity and by close proximity to gas stoves (source:  City of New York);
  • near, but not directly above, combustion appliances, such as furnaces, water heaters, and fireplaces, and in the garage (source:  UL); and
  • on the ceiling in the same room as permanently installed fuel-burning appliances, and centrally located on every habitable level, and in every HVAC zone of the building (source:  National Fire Protection Association 720). This rule applies to commercial buildings.
In North America, some national, state and local municipalities require installation of CO detectors in new and existing homes, as well as commercial businesses, among them:  Illinois, Massachusetts, Minnesota, New Jersey, Vermont and New York City, and the Canadian province of Ontario. Installers are encouraged to check with their local municipality to determine what specific requirements have been enacted in their jurisdiction.
How can I prevent CO poisoning?
  • Purchase and install carbon monoxide detectors with labels showing that they meet the requirements of the new UL standard 2034 or Comprehensive Safety Analysis 6.19 safety standards.
  • Make sure appliances are installed and operated according to the manufacturer's instructions and local building codes. Have the heating system professionally inspected by an InterNACHI inspector and serviced annually to ensure proper operation. The inspector should also check chimneys and flues for blockages, corrosion, partial and complete disconnections, and loose connections.
  • Never service fuel-burning appliances without the proper knowledge, skill and tools. Always refer to the owner's manual when performing minor adjustments and when servicing fuel-burning equipment.
  • Never operate a portable generator or any other gasoline engine-powered tool either in or near an enclosed space, such as a garage, house or other building. Even with open doors and windows, these spaces can trap CO and allow it to quickly build to lethal levels.
  • Never use portable fuel-burning camping equipment inside a home, garage, vehicle or tent unless it is specifically designed for use in an enclosed space and provides instructions for safe use in an enclosed area.
  • Never burn charcoal inside a home, garage, vehicle or tent.
  • Never leave a car running in an attached garage, even with the garage door open.
  • Never use gas appliances, such as ranges, ovens or clothes dryers to heat your home.
  • Never operate un-vented fuel-burning appliances in any room where people are sleeping.
  • During home renovations, ensure that appliance vents and chimneys are not blocked by tarps or debris. Make sure appliances are in proper working order when renovations are complete.
  • Do not place generators in the garage or close to the home. People lose power in their homes and get so excited about using their gas-powered generator that they don't pay attention to where it is placed. The owner's manual should explain how far the generator should be from the home.
  • Clean the chimney. Open the hatch at the bottom of the chimney to remove the ashes.  Hire a chimney sweep annually.
  • Check vents. Regularly inspect your home's external vents to ensure they are not obscured by debris, dirt or snow.
 

In summary, carbon monoxide is a dangerous poison that can be created by various household appliances. CO detectors must be placed strategically throughout the home or business in order to alert occupants of high levels of the gas.

To schedule your home inspection in San Antonio, TX, call 210-202-1974 or book online at www.vhillc.com

Sunday, May 28, 2017

Barbecue Safety

With tomorrow kicking off the summer, most of us will break out the BBQ sometime soon.  When you do, make sure you keep safety in mind.  And for tomorrow, take a moment to give thanks to the military men and women that gave their lives to allow us to live ours in freedom.
 
 
With barbecue season already here, homeowners should heed the following safety precautions in order to keep their families and property safe:

  • Propane grills present an enormous fire hazard, as the Consumer Product Safety Commission (CPSC) is aware of more than 500 fires that result annually from their misuse or malfunction. The following precautions are recommended specifically when using propane grills:
    • Store propane tanks outdoors and never near the grill or any other heat source. In addition, never store or transport them in your car’s trunk.
    • Make sure to completely turn off the gas after you have finished, or when you are changing the tank. Even a small gas leak can cause a deadly explosion. 
    • Check for damage to a tank before refilling it, and only buy propane from reputable suppliers.
    • Never use a propane barbecue grill on a terrace, balcony or roof, as this is dangerous and illegal.
    • No more than two 20-pound propane tanks are allowed on the property of a one- or two-family home.
    • To inspect for a leak, spray a soapy solution over the connections and watch for bubbles. If you see evidence of a leak, reconnect the components and try again. If bubbles persist, replace the leaking parts before using the grill.
    • Make sure connections are secure before turning on the gas, especially if the grill hasn’t been used in months. The most dangerous time to use a propane grill is at the beginning of the barbecue season.
    • Ignite a propane grill with the lid open, not closed. Propane can accumulate beneath a closed lid and explode.
    • When finished, turn off the gas first, and then the controls. This way, residual gas in the pipe will be used up.
  • Charcoal grills pose a serious poisoning threat due to the venting of carbon monoxide (CO). The CPSC estimates that 20 people die annually from accidentally ingesting CO from charcoal grills.  These grills can also be a potential fire hazard. Follow these precautions when using charcoal grills:
    • Never use a charcoal grill indoors, even if the area is ventilated. CO is colorless and odorless, and you will not know you are in danger until it is too late.
    • Use only barbecue starter fluid to start the grill, and don’t add the fluid to an open flame. It is possible for the flame to follow the fluid’s path back to the container as you're holding it.
    • Let the fluid soak into the coals for a minute before igniting them to allow explosive vapors to dissipate.
    • Charcoal grills are permitted on terraces and balconies only if there is at least 10 feet of clearance from the building, and a water source immediately nearby, such as a hose (or 4 gallons of water).
    • Be careful not to spill any fluid on yourself, and stand back when igniting the grill. Keep the charcoal lighter fluid container at a safe distance from the grill.
    • When cleaning the grill, dispose of the ashes in a metal container with a tight lid, and add water. Do not remove the ashes until they have fully cooled.
    • Fill the base of the grill with charcoal to a depth of no more than 2 inches.
  • Electric grills are probably safer than propane and charcoal grills, but safety precautions need to be used with them as well. Follow these tips when using electric grills:
    • Do not use lighter fluid or any other combustible materials. 
    • When using an extension cord, make sure it is rated for the amperage required by the grill. The cord should be unplugged when not in use, and out of a busy foot path to prevent tripping.
    • As always, follow the manufacturer's instructions.
Safety Recommendations for General Grill Use
  • Always make sure that the grill is used in a safe place, where kids and pets won't touch or bump into it. Keep in mind that the grill will still be hot after you finish cooking, and anyone coming into contact with it could be burned.
  • If you use a grill lighter, make sure you don't leave it lying around where children can reach it. They will quickly learn how to use it.
  • Never leave the grill unattended, as this is generally when accidents happen.
  • Keep a fire extinguisher or garden hose nearby.
  • Ensure that the grill is completely cooled before moving it or placing it back in storage.
  • Ensure that the grill is only used on a flat surface that cannot burn, and well away from any shed, trees or shrubs.
  • Clean out the grease and other debris in the grill periodically. Be sure to look for rust or other signs of deterioration.
  • Don't wear loose clothing that might catch fire while you're cooking.
  • Use long-handled barbecue tools and flame-resistant oven mitts.
  • Keep alcoholic beverages away from the grill; they are flammable!
In summary, homeowners should exercise caution when using any kind of grill, as they can harm life and property in numerous ways. 

Remember, you can schedule your home inspection by calling 210-202-1974 or book online at www.vhillc.com

Adapted with permission from https://www.nachi.org/barbeque-safety.htm by Nick Gromicko

Saturday, May 27, 2017

Attached Garage Fire Containment

To continue the information on garage fire safety, if the worst should happen, how can the fire be contained to the garage?
 
 

An attached garage is a garage that is physically attached to a house. Fires that begin in attached garages are more likely to spread to living areas than fires that originate in detached garages. For this reason, combined with the multitude of flammable materials commonly found in garages, attached garages should be adequately sealed from living areas. A properly sealed attached garage will ideally restrict the potential spread of fire long enough to allow the occupants time to escape the home or building.

Why are garages (both attached and detached) fire hazards?
  • Oil or gasoline can drip from cars. These fluids may collect unnoticed and eventually ignite.
  • Flammable liquids, such as gasoline, oil and paint, are commonly stored in garages. Some other examples are brake fluid, degreaser, motor oil, varnish, lighter fluid, and fluids containing solvents, such as paint thinner. These chemicals are flammable in their fluid form, and some may create explosive vapors.
  • Heaters and boilers, which are frequently installed in garages, create sparks that can ignite fumes or fluids. Car batteries, too, will spark under certain conditions.
  • Mechanical or electrical building projects are often undertaken in the garage. Fires can easily start while a careless occupant is welding near flammable materials. 
Doors
The 2006 edition of the International Residential Code (IRC) states the following concerning doors that separate garages from living areas:
R309.1 Opening Penetration
Openings from a private garage directly into a room used for sleeping purposes shall not be permitted. Other openings between the garage and the residence shall be equipped with solid wood doors not less than 1-3/8” (35 mm) in thickness, solid- or honeycomb-core steel doors not less than 1-3/8” (35 mm) thick, or 20-minute fire-rated doors.
In addition, Veteran Home Inspections can check for the following while inspecting doors that separate garages from living areas:
  • While not required by the IRC, it is helpful if there is at least one step leading up to the door from the garage. Gasoline fumes and other explosive gases are heavier than air, and they will accumulate at ground level. Their entry beneath a door will be slowed by an elevation increase.
  • Doors should have tight seals around their joints to prevent seepage of fumes into the living areas of the house. Carbon monoxide, with the same approximate density as air (and often warmer than surrounding air), will easily rise above the base of an elevated door and leak through unsealed joints.
  • Doors should be self-closing. Many homeowners find these doors inconvenient, but they are safer than doors that can be left ajar. While this requirement is no longer listed in the IRC, it is still a valuable recommendation.
  • If doors have windows, the glass should be fire-rated.
  • Pet doors should not be installed in fire-rated doors. Pet doors will violate the integrity of a fire barrier. 
Walls and Ceilings
The 2006 edition of the IRC states the following concerning garage walls and ceilings:
          R309.2 Separation Required
The garage shall be separated from the residence and its attic area by not less than 1/2-inch (12.7 mm) gypsum board applied to the garage side. Garages beneath habitable rooms shall be separated from all habitable rooms above by not less than 5/8-inch (15.9 mm) Type X gypsum board or equivalent. Where the separation is a floor-ceiling assembly, the structure supporting the separation shall also be protected by not less than 1/2-inch (12.7 mm) gypsum board or equivalent. Garages located less than 3 feet (914 mm) from a dwelling unit on the same lot shall be protected with not less than 1/2–inch (12.7 mm) gypsum board applied to the interior side of exterior walls that are within this area. Openings in these walls shall be regulated by Section 309.1. This provision does not apply to garage walls that are perpendicular to the adjacent dwelling unit wall.
In addition, inspectors can check for the following while inspecting walls and ceilings:
  • In garages that have access to the attic, a hatch cover made from an approved, fire-rated material should protect this access at all times. Missing or opened covers should be called out, as should covers made from flammable materials, such as thin plywood. Garage attic door must be constructed such that the 45-minute rating is maintained; any drywall edges on both the hatch and the surrounding area exposed to physical damage should be protected. The cover or door should be installed so that it is permanent (non-removable), with latching hardware to maintain it in a closed position. This could be accomplished by the use of spring-loaded hinges, a door closer, or hardware that will not allow it to be left in an open position when not in use. A single bolt-type or hook-and-eye hardware does not provide a positive closure, since these would allow the door to be left open. Likewise, drywall screws are fasteners--not hardware--so they cannot be used as the only means of keeping access doors closed.
  • The living space should be separated from the garage by a firewall that extends from the floor to the roof. If the ceiling material is fire-rated, the firewall can terminate at the ceiling.
  • Drywall joints shall be taped or sealed. Joints shall be fitted so that the gap is no more than 1/20-inch, with joints backed by either solid wood or another layer of drywall such that the joints are staggered. 
Ducts

The 2006 edition of the IRC states the following concerning ducts that penetrate garage walls and ceilings:
R309.1.1 Duct Penetration

Ducts in the garage and ducts penetrating the walls or ceilings separating the dwelling from the garage shall be constructed of a minimum No. 26-gauge (0.48 mm) steel sheet or other approved material, and shall have no openings in the garage.
Dryer exhaust ducts that penetrate garage walls are serious fire hazards. These ducts are generally made from plastic and will easily melt during a fire, creating a large breach in the firewall.

Floors

The 2006 edition of the IRC states the following concerning floors in garages:
          R309.3 Floor Surface
Garage floor surfaces shall be of approved, non-combustible material. The area of the floor used for parking of automobiles or other vehicles shall be sloped to facilitate the movement of liquids to a drain or toward the main vehicle entry doorway.
Inspectors should also check for the following:
  • A curb should be present along the perimeter of the garage floor. This curb should be designed to prevent fluids from entering the living areas of the house. Curbs are often useful barriers for melted snow carried into the garage by automobiles, but curbs can also keep chemical spills contained in the garage.
  • Water heaters should be elevated above the floor by at least 18 inches. A pilot light may ignite spilled fluid or floor-level flammable fumes if the water heater is placed at floor level.
Concerning items placed on the floor, inspectors should check for the following:
  • All flammable liquids should be stored in clearly labeled, self-closing containers, and in small amounts. They should be stored away from heaters, appliances, pilot lights, and other sources of heat and flame.
  • Propane tanks should never be stored indoors. If they catch fire, a serious explosion may result. Propane tanks are sturdy enough to be stored outdoors.
  • The floor should be clear of clutter. Loose papers, matches, oily rags, and other flammable items are dangerous if they are strewn about the garage floor.
General safety tips that inspectors can pass onto their clients:
  • Use light bulbs with the proper wattage.
  • Do not overload electrical outlets.
  • Tape down all cords and wires so that they are not twisted or accidentally yanked.
In summary, attached garages should be sealed off from the living space so that fire may be contained.

To schedule your home inspection, call Veteran Home Inspections at 210-202-1974 or schedule online at www.vhillc.com

Adapted with permission from https://www.nachi.org/attached-garage-fire-hazards.htm by Nick Gromicko and Kenton Shepard

Friday, May 26, 2017

Attached Garage Fire Hazards

The purpose of this article is twofold. First, at Veteran Home Inspections, we’d like you to take measures to keep your garage free from fire. Fortunately, there are ways this can be done, some of which are described below. Secondly, garage fires do happen, and we’d like you to make sure that a fire cannot not easily spread to the rest of your house. While you can perform many of the recommendations in this article yourself, it is a good idea to hire Veteran Home Inspections to make sure your home is safe from a garage fire.
Why do many garages pose a fire hazard?
  • Where are you most likely to do any welding, or any work on your car? These activities require working with all sorts of flammable materials.
  • Water heaters and boilers are usually stored in garages, and they can create sparks that may ignite fumes or fluids. Car batteries, too, will spark under certain conditions.
  • Oil and gasoline can drip from cars. These fluids may collect unnoticed and eventually ignite, given the proper conditions.
  • Flammable liquids, such as gasoline, motor oil and paint are commonly stored in garages. Some other examples are brake fluid, varnish, paint thinner and lighter fluid.
The following tips can help prevent garage fires and their spread:
  • If the garage allows access to the attic, make sure a hatch covers this access.
  • The walls and ceiling should be fire-rated. Unfortunately, it will be difficult for untrained homeowners to tell if their walls are Type X fire-rated gypsum. Our Certified Master Inspector can examine the walls and ceiling to make sure they are adequate fire barriers. 
  • The floor should be clear of clutter. Loose papers, matches, oily rags, and other potentially  flammable items are extremely dangerous if they are strewn about the garage floor.
  • Use light bulbs with the proper wattage, and do not overload electrical outlets.
  • Tape down all cords and wires so they are not twisted or accidentally yanked.
If there is a door that connects the garage to the living area, consider the following:
  • Do not install a pet door in the door! Flames can more easily spread into the living area through a pet door, especially if it’s made of plastic.
  • Does the door have a window? We can inspect the window to tell if it's fire-rated.
  • The door should be self-closing. While it may be inconvenient, especially while carrying groceries into the house from the car, doors should be self-closing. You never know when a fire will happen, and it would be unfortunate to accidentally leave the door open while a fire is starting in the garage.
  • Check the joints and open spaces around the door. Are they tightly sealed? Any openings at all can allow dangerous fumes, such as carbon monoxide or gasoline vapor, to enter the living area. We inspector can recommend ways to seal the door so that fumes cannot enter the living area.
Concerning items placed on the floor, you should check for the following:
  • Store your flammable liquids in clearly labeled, self-closing containers, and only in small amounts. Keep them away from heaters, appliances, pilot lights and other sources of heat or flame.
  • Never store propane tanks indoors. If they catch fire, they can explode. Propane tanks are sturdy enough to be stored outdoors.
  • Never bring charcoal grills (or ashes) inside the home or garage.  Even though you may think the coals are out, they can continue to smolder for days.  One of my neighbors almost lost his home when he threw coals in his garbage can 3 days after he grilled out.  The next morning the garbage can ignited and burned the side of his house.  Only an observant neighbor and a quick response from the San Antonio Fire Department saved his home.
In summary, there are plenty of things that you can do to prevent garage fires from spreading to the rest of the house, or to keep them from starting in the first place. However, it is highly recommended that you have your garage periodically examined by an inspector.

To schedule your home inspection, call Veteran Home Inspections at 210-202-1974 or schedule online at www.vhillc.com

Adapted with permission from https://www.nachi.org/garage-fires-client.htm by Nick Gromicko and Kenton Shepard

Thursday, May 25, 2017

Air Sampling for Mold Inspections

Since we are now certified to do mold testing, here is a quick article on the benefits and issues with doing air samples for mold testing.  Veteran Home Inspections can provide you with air sampling, tape lift sampling, and a complete mold inspection, which helps identify the causes of indoor mold. 


Taking air samples during a mold inspection is important for several reasons.  Mold spores are not visible to the naked eye, and the types of mold present can often be determinair sampleed through laboratory analysis of the air samples.  Having samples analyzed can also help provide evidence of the scope and severity of a mold problem, as well as aid in assessing human exposure to mold spores.  After remediation, new samples are typically taken to help ensure that all mold has been successfully removed.
 
Air samples can be used to gather data about mold spores present in the interior of a house.  These samples are taken by using a pump that forces air through a collection device which catches mold spores.  The sample is then sent off to a laboratory to be analyzed.  InterNACHI inspectors who perform mold inspections often utilize air sampling to collect data, which has become commonplace.
Air-Sampling Devices
There are several types of devices used to collect air samples that can be analyzed for mold.  Some common examples include:
  • impaction samplers that use a calibrated air pump to impact spores onto a prepared microscope slide;
  • cassette samplers, which may be of the disposable or one-time-use type, and also employ forced air to impact spores onto a collection media; and
  • airborne-particle collectors that trap spores directly on a culture dish.  These may be utilized to identify the species of mold that has been found.
When and When Not to Sample
Samples are generally best taken if visual, non-invasive examination reveals apparent mold growth or conditions that could lead to growth, such as moisture intrusion or water damage.  Musty odors can also be a sign of mold growth.  If no sign of mold or potential for mold is apparent, one or two indoor air samples can still be taken, at the discretion of the inspector and client, in the most lived-in room of the house and at the HVAC unit.  
Outdoor air samples are also typically taken as a control for comparison to indoor samples.  Two samples -- one from the windward side and one from the leeward side of the house -- will help provide a more complete picture of what is in the air that may be entering the house through windows and doors at times when they are open.  It is best to take the outdoor samples as close together in time as possible to the indoor samples that they will be compared with.
InterNACHI inspectors should avoid taking samples if a resident of the house is under a physician’s care for mold exposure, if there is litigation in progress related to mold on the premises, or if the inspector’s health or safety could be compromised in obtaining the sample.  Residential home inspectors also should not take samples in a commercial or public building.
Where to Sample and Ideal Conditions
In any areas of a house suspected or confirmed to have mold growth, air samples can be taken to help verify and gather more information.  Moisture intrusion, water damage, musty odors, apparent mold growth, or conditions conducive to mold growth are all common reasons to gather an air sample.  Samples should be taken near the center of the room, with the collection device positioned 3 to 6 feet off the ground.
Ten minutes is an adequate amount of time for the air pump to run while taking samples, but this can be reduced to around five minutes if there is a concern that air movement from a lot of indoor activity could alter the results.  The sampling time can be reduced further if there is an active source of dust, such as from ongoing construction.
Sampling should take place in livable spaces within the house under closed conditions in order to help stabilize the air and allow for reproducibility of the sampling and measurement.  While the sample is being collected, windows and exterior doors should be kept shut other than for normal entry and exit from the home.  It is best to have air exchangers (other than a furnace) or fans that exchange indoor-outdoor air switched off during sampling.
Weather conditions can be an important factor in gathering accurate data. Severe thunderstorms or unusually high winds can affect the sampling and analysis results.  High winds or rapid changes in barometric pressure increase the difference in air pressure between the interior and exterior, which can increase the variability of airborne mold-spore concentration.  Large differences in air pressure between the interior and exterior can cause more airborne spores to be sucked inside, skewing the results of the sample. 
Difficulties and Practicality of Air Sampling
It is helpful to think of air sampling as just one tool in the tool belt when inspecting a house for mold problems.  An air sample alone is not enough to confirm or refute the existence of a problem, and such testing needs to be accompanied by visual inspection and other methods of data collection, such as a surface sample.  Indoor airborne spore levels can vary according to several factors, and this can lead to skewed results if care is not taken to set up the sampling correctly.  Also, since only spores are collected with an air sample and may actually be damaged during collection, identification of the mold type can be more difficult than with a sample collected with tape or a cultured sample.
Air samples are good for use as a background screen to ensure that there isn’t a large source of mold not yet found somewhere in a home.  This is because they can detect long chains of spores that are still intact.  These chains normally break apart quickly as they travel through the air, so a sample that reveals intact chains can indicate that there is mold nearby, possibly undiscovered during other tests and visual examination. 
In summary, when taken under controlled conditions and properly analyzed, air samples for mold are helpful in comparing relative particle levels between a problem and a control area.  They can also be crucial for comparing particle levels and air quality in an area before and after mold remediation.  

To schedule your complete mold inspection and testing appointment, call 210-202-1974 or visit www.vhillc.com.

by Nick Gromicko and Ethan Ward
used with permission from: https://www.nachi.org/air-sampling-mold-inspection.htm

Friday, May 5, 2017

Termite Control in the Home

Veteran Home Inspections provides Wood Destroying Insect inspections for the San Antonio, TX and Hill Country area.  

The following is an article from our professional organization about termites and how to best control them in your home:

Wood-destroying insects and other organisms can cause serious problems in the wooden structural components of a house, and may go undetected for a long period of time.

New Construction
All chemical soil treatments, bait systems, and chemical wood treatment must be approved by the Environmental Protection Agency (EPA) and applied in accordance with the EPA label's instructions. In some cases, it is not feasible for a builder to arrange for soil treatment. In this regard, the International Residential Code (IRC) by the International Code Council allows a builder to utilize pressure-treated wood as a measure of termite protection. If pressure-treated wood is used, however, it must be used in all framing members up to and including the top plate of the first floor's level wall. This includes the sub-floor and floor joists of the first floor. The use of pressure-treated wood in only the sill plate is not acceptable. In such cases, the builder must provide the lender with a letter stating that the house is protected from termites by the use of pressure-treated wood. The builder must also provide the home buyer with a one-year warranty against termites. The use of post-construction soil treatment where the chemicals are applied only around the perimeter of the foundation is NOT acceptable in new construction.
Appraiser’s Observations
Appraisers are to observe all areas of the house and other structures/areas within the legal boundaries of the property that have potential for infestation by termites and other wood-destroying organisms, including the bottoms of exterior doors and frames, wood siding in contact with the ground, and crawlspaces. Mud tunnels running from the ground up the side of the house may indicate termite infestation. Observe the eaves and gable vents and wood window sills for indication of the entrance of swarming termites, and note excessive dampness or large areas where the vegetation is dead. Evidence of active termite infestation must be noted.
Termites 
 
Subterranean termites are the most damaging insects of wood. Their presence is hard to notice, and damage usually is found before the termites are seen. Prevent infestations because if they occur, they will almost always need professional pest-control service.
Signs of Infestation
Hire a qualified InterNACHI inspector to inspect for termites or other wood-destroying organisms. Generally, the first sign of infestation is the presence of swarming termites on the window or near indoor light. If they are found inside the house, it almost always means that they have infested. Other signs that may be found are termite wings on window sills or in cobwebs, and shelter tubes, which are tunnels constructed by the termites from soil or wood and debris. Usually, wood damage is not found at first, but when it is found, it definitely reveals a termite infestation. Anywhere wood touches soil is a possible entry into a home for termites. Examine wood which sounds dull or hollow when struck by a screwdriver or hammer. Inspect suspected areas with a sharp, pointed tool, such as an ice pick, to find termite galleries or their damage.
Control
Control measures include reducing the potential infestation, preventing termite entry, and applying chemicals for remedial treatment.
Inspection
Inspect thoroughly to determine if there is an infestation, damage, and/or conditions that could invite a termite attack, or the need for remedial control measures. The tools and equipment needed for an inspection include a flashlight, ice pick or sharp-pointed screwdriver, ladder, and protective clothing. Always hire an InterNACHI inspector for your inspection needs, as they are trained by the highest standards in the inspection industry.
Outdoors
Check the foundation of the house, garage and other buildings for shelter tubes coming from the soil. Look closely around porches, connecting patios, sidewalks, areas near kitchens and bathrooms, and hard-to-see places. Check window and door frames, and where utility services enter the house for termite infestation or wood decay. Also, look behind shrubbery and plants near walls. Pay special attention to areas where earth and wood meet, such as fences, stair carriages and trellises. Open and check any exterior electrical meter or fuse box set into the wall, a common point of infestation.
Indoors
Carefully check all doors, window facings, baseboards, and hardwood flooring. Discoloration or stains on walls or ceilings may mean that water is leaking and can decay wood, and this can aid termite infestation. It is very important to inspect where plumbing and utility pipes enter the foundation and flooring. Also, examine the attic for shelter tubes, water leakage, and wood damage.
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 Prevention
 Many termite problems can be prevented. The most important thing to do is to deny termites access to food (wood), moisture and shelter. Follow these suggestions:
  • have at least a 2-inch clearance between the house and planter boxes, or soil-filled porches;
  • eliminate all wood-to-soil contact, such as trellises, fence posts, stair casings and door facings (they can be put on masonry blocks or on treated wood);
  • separate shrubbery from the house to help make it easier to inspect the foundation line;
  • use wolmanized wood (pressure-treated wood) so that rain will not rot it;
  • seal openings through the foundation;
  • remove wood scraps and stumps from around the foundation;
  • have at least 12 to 18 inches of clearance between floor beams and the soil underneath.
Chemical Treatment
Termite treatment often requires specialized equipment. Therefore, it is recommended that you always use the services of a pest control operator because he is familiar with construction principles and practices, has the necessary equipment, and knows about subterranean termites.
Exterminating Termites 

If you think you have a termite infestation in your house, you need to call a structural pest control company to conduct a professional inspection. To find a company, ask friends or coworkers for recommendations, or check the Yellow Pages. If the inspection finds evidence of drywood termites, you have several options, depending on the degree of infestation. Fumigation and heating of the entire house are the only options that ensure eradication in the entire structure. If the infestation is contained in a small area, local or spot control may be effective. However, hidden infestations in other parts of the structure will not be eradicated.
Total (Whole-House) Eradication 
For the heat method, pets, plants, and other items that might be damaged by high temperatures must be removed. The house is then covered with tarps, and hot air is blown into the tarp until the inside temperature reaches 140° F to 150° F, and the temperature of the structural timbers reaches 120° F. The time to complete this procedure varies greatly from one structure to another, depending on factors such as the building's construction and the weather conditions. The procedure may not be practical for structures that cannot be heated evenly.
Local or Spot Control
Local or spot-control methods include the use of pesticides, electric current, extreme cold, localized heat, microwave energy, or any combination of these methods. Local or spot control also includes the removal and replacement of infested structural timber. These methods are intended to remove or kill termites only within the specific targeted area, leaving open the possibility of other undetected infestations within the structure. These treatments are NOT designed for whole-house eradication. Any pest control company that claims whole-house results with local or spot control methods is guilty of false advertising and should be reported.
Local or spot treatment with pesticides involves drilling and injecting pesticides into infested timbers, as well as the topical application of toxic chemicals. The electric-current method involves delivering electric energy to targeted infestations. For the extreme cold method, liquid nitrogen is pumped into wall voids adjacent to suspected infestation sites, reducing the area to -20° F. The localized heat method involves heating infested structural timbers to 120° F. The microwave method kills termites by directing microwaves into termite-infested wood.


If you see the following signs in your house, you might have termites:
  
• sawdust-like droppings; 
• dirt or mud-like tubes or trails on the structure; 
• damaged wood members (like window sills); and 
• swarming winged insects within the structure, especially in the spring or fall.

To schedule your home inspection with a wood destroying insect inspection, please call 210-202-1974 or schedule online at www.vhillc.com