Sunday, April 21, 2013

Safety Guidelines for Home Pools


Swimming pools should always be happy places. Unfortunately, each year thousands of American families confront swimming pool tragedies, drownings and near-drownings of young children. At InterNACHI, we want to prevent these tragedies. These are guidelines for pool barriers that can help prevent most submersion incidents involving young children. These guidelines are not intended as the sole method to minimize pool drowning of young children, but include helpful safety tips for safer pools.


Each year, hundreds of young children die and thousands come close to death due to submersion in residential swimming pools. The Consumer Product Safety Commission (CPSC) has estimated that each year, about 300 children under the age of 5 drown in swimming pools. Hospital emergency-room treatment is required for more than 2,000 children under 5 who were submerged in residential pools. The CPSC did an extensive study of swimming pool accidents, both fatal drownings and near-fatal submersions, in California, Arizona and Florida -- states in which home swimming pools are very popular and used during much of the year.
  • In California, Arizona and Florida, drowning was the leading cause of accidental death in and around the home for children under the age of 5.
  • Seventy-five percent of the children involved in swimming pool submersion or drowning accidents were between 1 and 3 years old. 
  • Boys between 1 and 3 were the most likely victims of fatal drownings and near-fatal submersions in residential swimming pools. 
  • Most of the victims were in the presence of one or both parents when the swimming pool accident occurred. 
  • Nearly half of the child victims were last seen in the house before the pool accident occurred. In addition, 23% of the accident victims were last seen on the porch or patio, or in the yard. 
  • This means that 69% of the children who became victims in swimming pool accidents were not expected to be in or at the pool, but were found drowned or submerged in the water. 
  • Sixty-five percent of the accidents occurred in a pool owned by the victim’s immediate family, and 33% of the accidents occurred in pools owned by relatives or friends. 
  • Fewer than 2% of the pool accidents were the result of children trespassing on property where they didn’t live or belong. 
  • Seventy-seven percent of the swimming pool accident victims had been missing for five minutes or less when they were found in the pool, drowned or submerged. 
The speed with which swimming pool drownings and submersions can occur is a special concern: by the time a child’s absence is noted, the child may have drowned. Anyone who has cared for a toddler knows how fast young children can move. Toddlers are inquisitive and impulsive, and lack a realistic sense of danger. These behaviors, coupled with a child’s ability to move quickly and unpredictably, make swimming pools particularly hazardous for households with young children.

 
Swimming pool drownings of young children have another particularly insidious feature: these are silent deaths. It is unlikely that splashing or screaming will occur to alert a parent or caregiver that a child is in trouble. The best way to reduce child drownings in residential pools is for pool owners to construct and maintain barriers that prevent young children from gaining access to pools. However, there are no substitutes for diligent supervision.
 
Why the Swimming Pool Guidelines Were Developed
 
Young child can get over a pool barrier if the barrier is too low, or if the barrier has handholds or footholds for a child to use for climbing. The guidelines recommend that the top of a pool barrier be at least 48 inches above grade, measured on the side of the barrier which faces away from the swimming pool. Eliminating handholds and footholds, and minimizing the size of openings in a barrier’s construction, can prevent inquisitive children from climbing pool barriers.
 
For a solid barrier, no indentations or protrusions should be present, other than normal construction tolerances and masonry joints. For a barrier (fence) made up of horizontal and vertical members, if the distance between the tops of the horizontal members is less than 45 inches, the horizontal members should be on the swimming pool-side of the fence. The spacing of the vertical members should not exceed 1-3/4 inches. This size is based on the foot-width of a young child, and is intended to reduce the potential for a child to gain a foothold. If there are any decorative cutouts in the fence, the space within the cutouts should not exceed 1-3/4 inches.
 
The definition of pool includes spas and hot tubs. The swimming pool-barrier guidelines, therefore, apply to these structures, as well as to conventional swimming pools.
 
How to Prevent a Child from Getting OVER a Pool Barrier
 
A successful pool barrier prevents a child from getting OVER, UNDER or THROUGH, and keeps the child from gaining access to the pool except when supervising adults are present.
 
The Swimming Pool-Barrier Guidelines
 
If the distance between the tops of the horizontal members is more than 45 inches, the horizontal members can be on the side of the fence facing away from the pool. The spacing between vertical members should not exceed 4 inches. This size is based on the head-breadth and chest depth of a young child, and is intended to prevent a child from passingthrough an opening. Again, if there are any decorative cutouts in the fence, the space within the cutouts should not exceed 1-3/4 inches.
 
For a chain-link fence, the mesh size should not exceed 1-1/4 inches square, unless slats fastened at the top or bottom of the fence are used to reduce mesh openings to no more than 1-3/4 inches.
For a fence made up of diagonal members (lattice work), the maximum opening in the lattice should not exceed 1-3/4 inches.
 
Above-ground pools should have barriers. The pool structure itself can sometimes serves as a barrier, or a barrier can be mounted on top of the pool structure. Then, there are two possible ways to prevent young children from climbing up into an above-ground pool. The steps or ladder can be designed to be secured, locked or removed to prevent access, or the steps or ladder can be surrounded by a barrier, such as those described above. For any pool barrier, the maximum clearance at the bottom of the barrier should not exceed 4 inches above grade, when the measurement is done on the side of the barrier facing away from the pool.

If an above-ground pool has a barrier on the top of the pool, the maximum vertical clearance between the top of the pool and the bottom of the barrier should not exceed 4 inches. Preventing a child from getting through a pool barrier can be done by restricting the sizes of openings in a barrier, and by using self-closing and self-latching gates. 

To prevent a young child from getting through a fence or other barrier, all openings should be small enough so that a 4-inch diameter sphere cannot pass through. This size is based on the head- breadth and chest-depth of a young child.
 
Gates 
There are two kinds of gates which might be found on a residential property. Both can play a part in the design of a swimming pool barrier. 
 
Pedestrian gates are the gates people walk through. Swimming pool barriers should be equipped with a gate or gates which restrict access to the pool. A locking device should be included in the gate's design. Gates should open out from the pool and should be self-closing and self-latching. If a gate is properly designed, even if the gate is not completely latched, a young child pushing on the gate in order to enter the pool area will at least close the gate and may actually engage the latch. When the release mechanism of the self-latching device is less than 54 inches from the bottom of the gate, the release mechanism for the gate should be at least 3 inches below the top of the gate on the side facing the pool. Placing the release mechanism at this height prevents a young child from reaching over the top of a gate and releasing the latch. Also, the gate and barrier should have no opening greater than 1/2-inch within 18 inches of the latch release mechanism. This prevents a young child from reaching through the gate and releasing the latch.
  
Other gates should be equipped with self-latching devices. The self-latching devices should be installed as described for pedestrian gates. 
 
How to Prevent a Child from Getting UNDER or THROUGH a Pool Barrier 
In many homes, doors open directly onto the pool area or onto a patio which leads to the pool. In such cases, the wall of the house is an important part of the pool barrier, and passage through any doors in the house wall should be controlled by security measures. The importance of controlling a young child’s movement from the house to the pool is demonstrated by the statistics obtained during the CPSC’s study of pool incidents in California, Arizona and Florida. Almost half (46%) of the children who became victims of pool accidents were last seen in the house just before they were found in the pool. 
All doors which give access to a swimming pool should be equipped with an audible alarm which sounds when the door and/or screen are opened. The alarm should sound for 30 seconds or more within seven seconds after the door is opened.  It should also be loud, at least 85 decibels, when measured 10 feet away from the alarm mechanism. The alarm sound should be distinct from other sounds in the house, such as the telephone, doorbell and smoke alarm. The alarm should have an automatic re-set feature. Because adults will want to pass through house doors in the pool barrier without setting off the alarm, the alarm should have a switch that allows adults to temporarily de-activate the alarm for up to 15seconds. The de-activation switch could be a touch pad (keypad) or a manual switch, and should be located at least 54 inches above the threshold of the door covered by the alarm. This height was selected based on the reaching ability of young children.
Power safety covers can be installed on pools to serve as security barriers. Power safety covers should conform to the specifications in ASTM F 1346-91. This standard specifies safety performance requirements for pool covers to protect young children from drowning. Self-closing doors with self-latching devices could also be used to safeguard doors which give ready access to a swimming pool.
 
Indoor Pools
 
When a pool is located completely within a house, the walls that surround the pool should be equipped to serve as pool safety barriers. Measures recommended above where a house wall serves as part of a safety barrier also apply for all the walls surrounding an indoor pool. 
 
Guidelines
 
An outdoor swimming pool, including an in-ground, above-ground, or on-ground pool, hot tub, or spa, should be provided with a barrier which complies with the following:
 
1. The top of the barrier should be at least 48 inches above grade, measured on the side of the barrier which faces away from the swimming pool. The maximum vertical clearance between grade and the bottom of the barrier should be 4 inches measured on the side of the barrier which faces away from the swimming pool. Where the top of the pool structure is above grade, such as an above-ground pool, the barrier may be at ground level, such as the pool structure, or mounted on top of the pool structure. Where the barrier is mounted on top of the pool structure, the maximum vertical clearance between the top of the pool structure and the bottom of the barrier should be 4 inches.

 
2. Openings in the barrier should not allow passage of a 4-inch diameter sphere.
 
3. Solid barriers, which do not have openings, such as a masonry and stone wall, should not contain indentations or protrusions, except for normal construction tolerances and tooled masonry joints.

 
4. Where the barrier is composed of horizontal and vertical members, and the distance between the tops of the horizontal members is less than 45 inches, the horizontal members should be located on the swimming pool-side of the fence. Spacing between vertical members should not exceed 1-3/4 inches in width. Where there are decorative cutouts, spacing within the cutouts should not exceed 1-3/4 inches in width.
 
5. Where the barrier is composed of horizontal and vertical members, and the distance between the tops of the horizontal members is 45 inches or more, spacing between vertical members should not exceed 4 inches. Where there are decorative cutouts, spacing within the cutouts should not exceed 1-3/4 inches in width.

 
6. The maximum mesh size for chain-link fences should not exceed 1-3/4 inch square, unless the fence is provided with slats fastened at the top or the bottom which reduce the openings to no more than 1-3/4 inches.
 
7. Where the barrier is composed of diagonal members, such as a lattice fence, the maximum opening formed by the diagonal members should be no more than 1-3/4 inches.
  
8. Access gates to the pool should be equipped to accommodate a locking device. Pedestrian access gates should open outward, away from the pool, and should be self-closing and have a self-latching device. Gates other than pedestrian access gates should have a self-latching device, where the release mechanism of the self-latching device is located lessthan 54 inches from the bottom of the gate.
  • The release mechanism should be located on the pool-side of the gate at least 3 inches below the top of the gate.
  • The gate and barrier should have no opening greater than 1/2-inch within 18 inches of the release mechanism.
9. Where a wall of a dwelling serves as part of the barrier, one of the following should apply:
  • All doors with direct access to the pool through that wall should be equipped with an alarm which produces an audible warning when the door and its screen, if present, are opened. The alarm should sound continuously for a minimum of 30 seconds within seven seconds after the door is opened. The alarm should have a minimum sound pressure rating of 85 dBA at 10 feet, and the sound of the alarm should be distinctive from other household sounds, such as smoke alarms, telephones and doorbells. The alarm should automatically re-set under all conditions. The alarm should be equipped with manual means, such as touchpads or switches, to temporarily de-activate the alarm for a single opening of the door from either direction. Such de-activation should last for no more than 15 seconds. The de-activation touch pads or switches should be located at least 54 inches above the threshold of the door.
  • The pool should be equipped with a power safety cover which complies with ASTM F1346-91. 
  • Other means of protection, such as self-closing doors with self-latching devices, are acceptable as long as the degree of protection afforded is not less than the protection afforded by the above.
10. Where an above-ground pool structure is used as a barrier, or where the barrier is mounted on top of the pool structure, and the means of access is a ladder or steps, then:
  • The ladder to the pool or steps should be capable of being secured, locked or removed to prevent access.
  • The ladder or steps should be surrounded by a barrier. When the ladder or steps are secured, locked, or removed, any opening created should not allow the passage of a 4-inch diameter sphere.
These guidelines are intended to provide a means of protection against potential drownings of children under 5 years of age by restricting access to residential swimming pools, spas and hot tubs.
 
Exemptions
 
A portable spa with a safety cover which complies with ASTM F1346-91 should be exempt from the guidelines presented here. Swimming pools, hot tubs, and non-portable spas with safety covers should not be exempt from these provisions.
 


From Safety Guidelines for Home Pools - InterNACHI http://www.nachi.org/poolsafety.htm#ixzz2R8U8xEqM

Monday, April 15, 2013

Bathroom Ventilation Ducts and Fans


by Nick Gromicko and Kenton Shepard

 
 
Bathroom ventilation systems are designed to exhaust odors and moist air to the home's exterior. Typical systems consist of a ceiling fan unit connected to a duct that terminates at the roof.
 
Fan Function  
 
 The fan may be controlled in one of several ways:
  • Most are controlled by a conventional wall switch.
  • A timer switch may be mounted on the wall.
  • A wall-mounted humidistat can be pre-set to turn the fan on and off based on different levels of relative humidity.
Newer fans may be very quiet but work just fine. Older fans may be very noisy or very quiet. If an older fan is quiet, it may not be working well. Inspectors can test for adequate fan airflow with a chemical smoke pencil or a powder puff bottle, but such tests exceed InterNACHI's Standards of Practice.

Bathroom ventilation fans should be inspected for dust buildup that can impede air flow. Particles of moisture-laden animal dander and lint are attracted to the fan because of its static charge. Inspectors should comment on dirty fan covers.
Ventilation systems should be installed in all bathrooms. This includes bathrooms with windows, since windows will not be opened during the winter in cold climates.
 
Defects
 
The following conditions indicate insufficient bathroom ventilation:
  • moisture stains on walls or ceilings;
  • corrosion of metal;
  • visible mold on walls or ceilings;
  • peeling paint or wallpaper;
  • frost on windows; and
  • high levels of humidity.
The most common defect related to bathroom ventilation systems is improper termination of the duct. Vents must terminate at the home exterior.
 
The most common improper terminations locations are:
  • mid-level in the attic. These are easy to spot;
  • beneath the insulation. You need to remember to look. The duct may terminate beneath the insulation or there may be no duct installed; and 
  • under attic vents. The duct must terminate at the home exterior, not just under it.
Improperly terminated ventilation systems may appear to work fine from inside the bathroom, so the inspector may have to look in the attic or on the roof. Sometimes, poorly installed ducts will loosen or become disconnected at joints or connections.
 
Ducts that leak or terminate in attics can cause problems from condensation. Warm, moist air will condense on cold attic framing, insulation and other materials. This condition has the potential to cause health and/or decay problems from mold, or damage to building materials, such as drywall. Moisture also reduces the effectiveness of thermal insulation.

Mold
 
Perhaps the most serious consequence of an improper ventilation setup is the potential accumulation of mold in attics or crawlspaces. Mold may appear as a fuzzy, thread-like, cobwebby fungus, although it can never be identified with certainty without being lab-tested. Health problems caused by mold are related to high concentrations of spores in indoor air.  Spores are like microscopic seeds, released by mold fungi when they reproduce. Every home has mold. Moisture levels of about 20% in materials will cause mold colonies to grow. Inhaling mold spores can cause health problems in those with asthma or allergies, and can cause serious or fatal fungal infections in those with lung disease or compromised immune systems.

Mold is impossible to identify visually and must be tested by a lab in order to be confidently labeled. Inspectors should refrain from calling anything “mold” but should refer to anything that appears as mold as a material that “appears to be microbial growth.” Inspectors should include in their report, and in the inspection agreement signed by the client, a disclaimer clearly stating that the General Home Inspection is an inspection for safety and system defects, not a mold inspection.

Decay, which is rot, is also caused by fungi. Incipient or early decay cannot be seen. By the time decay becomes visible, affected wood may have lost up to 50% of its strength.

In order to grow, mold fungi require the following conditions to be present:
  • oxygen;
  • temperatures between approximately 45° F and 85° F;
  • food. This includes a wider variety of materials found in homes; and
  • moisture.
If insufficient levels of any of these requirements exist, all mold growth will stop and fungi will go dormant. Most are difficult to actually kill.

Even though mold growth may take place in the attic, mold spores can be sucked into the living areas of a residence by low air pressure. Low air pressure is usually created by the expulsion of household air from exhaust fans in bathrooms, dryers, kitchens and heating equipment.

Improper Ventilation
 
Ventilation ducts must be made from appropriate materials and oriented effectively in order to ensure that stale air is properly exhausted.
 
Ventilation ducts must:
  • terminate outdoors. Ducts should never terminate within the building envelope;
  • contain a screen or louvered (angled) slats at its termination to prevent bird, rodent and insect entry;
  • be as short and straight as possible and avoid turns. Longer ducts allow more time for vapor to condense and also force the exhaust fan to work harder;
  • be insulated, especially in cooler climates. Cold ducts encourage condensation;
  • protrude at least several inches from the roof;
  • be equipped with a roof termination cap that protects the duct from the elements; and 
  • be installed according to the manufacturer's recommendations.
The following tips are helpful, although not required. Ventilation ducts should:
  • be made from inflexible metal, PVC, or other rigid material. Unlike dryer exhaust vents, they should not droop; and 
  • have smooth interiors. Ridges will encourage vapor to condense, allowing water to back-flow into the exhaust fan or leak through joints onto vulnerable surfaces.
Above all else, a bathroom ventilation fan should be connected to a duct capable of venting water vapor and odors into the outdoors. Mold growth within the bathroom or attic is a clear indication of improper ventilation that must be corrected in order to avoid structural decay and respiratory health issues.


From Bathroom Ventilation Ducts and Fans - InterNACHI http://www.nachi.org/bathroom-ventilation-ducts-fans.htm#ixzz2QZyW6FKD