Telecom Cabling Fire Stopping

Telecom Cabling The United States has the highest rate of deaths by fire in the world. Approximately 5,300 people die in fires and another 29,000 are injured annually. Furthermore, more than 100 fire fighters die each year fighting fires. As a matter of fact, fire kills more Americans than all other natural disasters combined.

Telecom Cabling Our homes, including multi-family dwellings, are the most vulnerable (more than 80% of all fire deaths occur in residences). So what do you think are the top 5 causes of residential fires?

Telecom Cabling The 5 most common causes of fires that make the list consistently are: Cooking equipment Heating equipment Careless smoking Electrical equipment/appliances Candles

Telecom Cabling Some other common causes of fires include Christmas trees, children playing with fire, fire places, barbecues and stored flammable liquids…..and there are still more possible causes of fire. You may want to invest in a fire extinguisher right about now.

Telecom Cabling It should be clear why proper fire stopping is such a critical issue, it’s similar to the purpose of the code and other NFPA publications. Life Safety

Fire protection covers three broad areas: Telecom Cabling Fire protection covers three broad areas: PREVENTION CONTAINMENT SUPPRESSION

Telecom Cabling Prevention is the precautions taken to prevent or reduce the likelihood of a fire that might result in death, injury or property damage. Containment is a passive system that protects by their inherent properties to prevent the spread of fire. Suppression is an active system that protects by the use of external energy sources like electricity, water pressure or human intervention.

Telecom Cabling When ever we establish our cable pathways through a building it is very likely that at some point we will pass through a fire wall. When passing through a fire wall we have to bring the wall back to it’s original fire rating.

Telecom Cabling What does the NEC tell us about fire stopping, article 300.21: Electrical installations in hollow spaces, vertical shafts, and ventilation or air-handling ducts shall be made so that the possible spread of fire or products of combustion will not be substantially increased. Openings around electrical penetrations through fire resistant-rated walls, partitions, floors, or ceilings shall be fire stopped using approved methods to maintain the fire resistance rating.

Telecom Cabling As you can see the NEC doesn’t tell us how to fire stop or what to use for fire stopping. It simply states that we shall use the approved method of fire stopping. There are several companies that offer solutions for fire stopping and there are the best practices that many electrical and low voltage companies use to fire stop that have been approved.

Telecom Cabling So how do we identify a fire wall? What is a typical fire wall rating? These are things you need to be aware of when installing any type of low voltage system in any type of building. Ultimately you will be held responsible for what you do or don’t do on a site.

Telecom Cabling Lets look at the definition of a fire wall: A continuous (basement to ceiling) wall having adequate fire resistance rating (expressed in hours) with an adequate structural stability under fire conditions to completely subdivide a building or completely separate adjoining buildings to restrict the spread of fire.

Telecom Cabling A fire rated partition is a partition having an assembly of materials that will afford a given fire resistance rating (expressed in hours) to impede the spread of fire from one area to another. This is the type of fire wall you’re most likely to encounter on a customer’s site.

Telecom Cabling A fire rated partition wall: Two layers of 5/8” sheet rock that goes all the way up to the deck is a fire wall, this type of wall has a 2 hour “F” rating. This is a 1 hour rated wall, it has two layers of sheet rock, why is it only rated for 1 hour and not 2? HINT

Telecom Cabling When you look up you will see the sheet rock goes all the way up to the corrugated deck. All of the seams and bar joists have been fire stopped.

Telecom Cabling Another type of wall that you may encounter is a block wall, on the blue prints its identified as a CMU (concrete masonry unit) wall and these walls are also fire rated partition walls which are typically at least a 2 hour wall.

Telecom Cabling You will often run into a block wall in hallways, they’re above the fire doors which are being held open by electro-magnetic devices. Keep this in mind if your cable pathways are running down hallways which is very typical.

Telecom Cabling When passing through a fire wall we install a metallic sleeve (EMT) with bang on plastic bushings and secure the sleeve with minerallac conduit hangers and then fire stop.

Telecom Cabling The resulting install looks like the side view below, these are installs that AHJs have approved.

Telecom Cabling It is a good idea to keep pre-cut sleeves with all the material needed for penetrations on the service van ready to go as needed. For large cable pathways utilizing tray systems we normally use 4” sleeves. In most instances a 2” sleeve should be the minimum to anticipate future growth (future proofing).

Telecom Cabling There are many other solutions that accomplish the same thing.

Telecom Cabling Here is a fairly new product….a little pricey.

Telecom Cabling It is important that we use a re-enterable fire stop material since we’re always going back for moves, adds and changes (MACs). These come in the form of fire stop putty which is like a soft clay.

Telecom Cabling Some other materials that are used regularly for fire stopping any site are the fire stop caulking, this dries to a very hard semi pliable barrier that is very difficult to remove so it is not recommended for use in sleeves.

Telecom Cabling Intumescent pillows are used for fire blocking large openings in walls such as where cable trays or pipe banks pass through. Intumescent means that it expands when heated.

Telecom Cabling Riser systems require the use of mineral wool stuffed into the pipe to keep fire stop from falling down into the pipe.

Telecom Cabling All fire stop material shall be UL listed. UL LISTING

Telecom Cabling Fire stop systems and materials have a rating system. F = Flame measured in hours T = Temperature measured in hours L = Air leakage measured in cubic feet per minute

Telecom Cabling Once you’ve completed installing your fire stop system you have to document it, this requires placing a label next to the penetration that includes the company name, address, the installers name, date and materials used.

Telecom Cabling If you’re on a service call and have to pass through an existing fire stop sleeve it is a very good idea to take a photo of the fire stop after completing your cable pulls to verify that you brought the wall back up to it’s fire stop rating. As the installer or technician you will be held accountable by government agencies for failure to fire stop.