Attached Garage Fire Containment

   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.
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Backflow Prevention

  Back-flow is the reversal of the normal and intended direction of water flow in a water system. Devices and assemblies known as back-flow preventers are installed to prevent back-flow, which can contaminate potable water supplies.

Why is back-flow a problem?
  Back-flow is a potential problem in a water system because it can spread contaminated water back through a distribution system. For example, back-flow at uncontrolled cross connections (cross-connections are any actual or potential connection between the public water supply and a source of contamination or pollution) can allow pollutants or contaminants to enter the potable water system. Sickness can result from ingesting water that has been contaminated due to back-flow.

Backflow may occur under the following two conditions:

back-pressure: Back-pressure is the reverse from normal flow direction within a piping system as the result of the downstream pressure being higher than the supply pressure. This reduction in supply pressure occurs whenever the amount of water being used exceeds the amount of water being supplied (such as during water-line flushing, fire-fighting, or breaks in water mains).

back-siphonage: Back-siphonage is the reverse from normal flow direction within a piping system that is caused by negative pressure in the supply piping (i.e., the reversal of normal flow in a system caused by a vacuum or partial vacuum within the water supply piping). Back-siphonage can occur when there is a high velocity in a pipe line, when there is a line repair or break that is lower than a service point, or when there is lowered main pressure due to high-water withdrawal rate (such as during fire-fighting or water-main flushing)
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