Fire Dampers

[Robert Foster]

I inspected a high end town home today in a multi story building... a first for me. The supply registers located in the ceiling for the heat pump were labeled as Fire Dampers. I understand what the function of these are, but not sure how to handle them in my report. I read the NFPA wants them inspected every 6 years, and assume these are inspected by either a specialized HVAC company or maybe the fire marshal, but I doubt the fire marshal does that. Is that correct about needing a specialized inspection every few years ?

I know there's a bunch I don't know here and looking for some guidance about what I need/should/should not put into my report concerning the Fire Dampers to help my client and cover myself.

[Garry Blankenship]

I am hoping someone here knows more than I because I have never heard of HVAC registers, ceiling or floor, being fire dampers. Though they typically are not abusive with their power, Fire Marshalls are next to untouchable. If they want it, they get it. I think the/a AHJ Mayor or Governor are about the only ones that can tell a Fire Marshall how it's gonna be and that is only by threatening them w/ their job.

[Doctor Haus]

I inspected a high end town home today in a multi story building... a first for me. The supply registers located in the ceiling for the heat pump were labeled as Fire Dampers. I understand what the function of these are, but not sure how to handle them in my report. I read the NFPA wants them inspected every 6 years, and assume these are inspected by either a specialized HVAC company or maybe the fire marshal, but I doubt the fire marshal does that. Is that correct about needing a specialized inspection every few years ?

I know there's a bunch I don't know here and looking for some guidance about what I need/should/should not put into my report concerning the Fire Dampers to help my client and cover myself.

Life Safety Dampers are to be inspected following installation and in general fire dampers are to be maintained and inspected/tested at least every four years.

This is generally the responsiblity of building management. They may have in-house personel or use an outside firm.

The IBC, the IPM, and other codes reference NFPA Codes. UL references are here UL | Dampers (http://www.ul.com/global/eng/pages/offerings/perspectives/regulator/electrical/additionalresources/dampers/)

[Jerry Peck]

I inspected a high end town home today in a multi story building... a first for me. The supply registers located in the ceiling for the heat pump were labeled as Fire Dampers. I understand what the function of these are, but not sure how to handle them in my report.

I would also notify my client that the ceiling/floor (if this is not the top floor unit) or ceiling/attic/roof (if this is a top floor unit) is the fire-rated separation between the units, which means they should NOT be making any holes of any type for any reason in the ceiling (not even swag hooks). Likewise, they should not be making any holes of any type for any reason in the floor either.

Typically, in my experience, in multi-story (i.e., mid-rise and high rise) buildings the fire-rated separation is the concrete slab separating the stories at the floor/ceiling, and ceilings dropped down from those concrete floors are not the fire-rated separation. Makes things a lot safer that way.

[Rod Butler]

I am hoping someone here knows more than I because I have never heard of HVAC registers, ceiling or floor, being fire dampers. Though they typically are not abusive with their power, Fire Marshalls are next to untouchable. If they want it, they get it. I think the/a AHJ Mayor or Governor are about the only ones that can tell a Fire Marshall how it's gonna be and that is only by threatening them w/ their job.

The registers may have a sticker on them indicating that there is a fire damper and access is thru the grille face.

Typically a fire damper is NOT required just because a duct is passing thru a fire rated partition, it is because it has an opening on both sides of the separation.

In this case I would guess that the other opening(s) is in an adjacent area that is not part of the tenant's area and therefore fall under the responsibility of the building management.

I realize there is a whole lot of ASS-U-ME-(ing) going on here but hopefully there is some benefit gained from these responses.

[Jerry Peck]

Typically a fire damper is NOT required just because a duct is passing thru a fire rated partition, it is because it has an opening on both sides of the separation.

There are two types of penetrations:
a) Membrane penetrations: such as an electrical box set in the wall and penetrate the wall plane (penetrate the membrane) and into, but not through, the fire-rated construction.
b) Through penetrations: such as ducts, which go through the fire-rated construction.

A membrane penetration can be protected by (as an example for electrical boxes) protecting the outside of the electrical box with putty pads, or the inside if the putty pad is rated for that and if the box does not have much wire/device fill.

The through penetration needs to have the fire damper so the opening can be closed off in the even of a fire. An exception to this is the use of fire protected ducts or, in the case of clothes dryer vents, the use of 26 gauge sheet metal instead of 30 gauge sheet metal. The 26 gauge exception may also apply to ductwork from other appliances.

Most dampers for this (ducts) will be fusible link, which is a link that melts/releases when the temperature rises and allows the spring loaded damper to close. Other dampers, usually for other uses, are electro-mechanical as they are electrically operated with motors which close the mechanical vanes, and when the alarm is cleared and reset, the dampers will open back up. Fusible link dampers must be manually opened and the fusible link replaced.

In the even of a fire, the dampers will likely need to be replaced.