Fire Dampers in the Pneumatic Tube System?

Q: Our pneumatic tube vendor is telling our Engineering folks that they have to install dampers inside the system everywhere that a pneumatic tube run penetrates a fire wall or floor. I’ve never heard of this, have you?

A: I don’t see that as a requirement with the NFPA codes and standards. My first thought is for you to just ask this vendor on what code or standard he is making that claim. It is possible that a local or state authority made this a requirement at a previous project and he is just being over-zealous in wanting to make sure the job is done right, as he understands it.

Here is a code search that may shed more light on this subject. (All references are to the 2000 Life Safety Code.) Section says openings in fire barriers for air-handling ductwork or air movement shall be protected in accordance with section 9.2.1. Section 9.2.1 requires compliance with NFPA 90A which is the standard that requires the installation of fire dampers in various locations of fire rated barriers. Since only requires openings in fire barriers for air-handling ductwork or air movement purposes to comply with NFPA 90A, then there is no requirement for a pneumatic tube to have fire dampers because it is not used to move air through fire rated barriers; it is used to move carriers through fire walls, by using differences in air pressure. It would be similar to a large electrical conduit.

Make the vendor shown you the standard that he says requires dampers. Then see if it applies to your situation.

Fire Dampers in Rated Walls

Q: Are fire dampers required in 1-hour fire rated walls if the facility is fully sprinkled? Also, we have a couple of inaccessible dampers and I was wondering if I needed to add them on the Statement of Conditions PFI list? 

A: According to NFPA 90A (1999 edition), 1-hour fire rated barriers do not require fire dampers in fully ducted HVAC systems, unless the 1-hour fire rated barrier is a vertical shaft. If the air duct is an air transfer opening (meaning it is not fully ducted) at the fire rated barrier, then the duct needs a fire damper where other openings are required to be protected as well. However, 2-hour fire rated barriers do require fire dampers in fully ducted HVAC systems. Being fully sprinklered, or not, has no bearing on the requirement whether fire dampers are required. It does have a bearing on whether or not smoke dampers are needed, though.

Inaccessible fire dampers are a life safety code deficiency, and must be addressed by the following:

  • The inaccessible fire dampers must be assessed for Interim Life Safety Measures (ILSM)
  • A decision must be made as to whether or not you will make the fire dampers accessible, and therefore be able to test them
  • If you cannot resolve the inaccessible fire dampers within 45 days of discovery, they must be placed on the PFI list of the Statement of Conditions.
  • If you decide you will not resolve the inaccessible fire dampers, then the projected completion date for the PFI may be set at 6-years. After 6 years, re-examine the inaccessible fire damper to determine if the environment has changed, and if they are still inaccessible, then close out the PFI, and open a new one for another 6-year cycle.

Joint Commission surveyors are very astute to identifying inaccessible fire dampers, and whether or not you placed them on the PFI list, and whether or not you assessed them for ILSMs. So, make sure you assess them for ILSMs, and place them on the PFI list.

Fire Damper Installation

Q: Do you need a fire smoke damper at floor level in an open duct shaft? Or where the duct comes out through the shaft wall?

A: Section of the 2000 edition of the Life Safety Code requires compliance with section 9.2. Section 9.2.1 requires compliance with NFPA 90A Installation of Air Conditioning and Ventilation Systems, 1999 edition. If you have a copy of that standard, take a look at Figure A-3-3 in the appendix of the book, and there is a real nifty diagram that points out all of the possible locations where fire and smoke dampers would be required. But, to directly answer your questions, section 3-3.2 of NFPA 90A requires a fire damper at the floor level of any HVAC duct that penetrates a fire-rated floor if the duct is not enclosed within a fire rated shaft. But section 3-3.4.1 says an air duct that pass through floors of buildings that require the protection of vertical opening (such as a hospital would), must be enclosed with walls with 1-hour fire resistance rating if the shaft penetrates 3 or less stories, and 2-hour fire resistance rating if the shaft penetrates 4 or more stories. The exception to 3-3.4.1 says you do not need a fire rated shaft if the air duct passes through only one floor, or if the air duct passes through only one floor and an air-handling equipment penthouse floor, whereby the air duct would require a fire damper where the duct penetrates the floor. In reply to your second question… According to section 3-3.4.4, fire dampers are required in any opening into or out of a shaft required in 3-3.4.1, whether or not the shaft opening contains an air duct or is ductless. A fire damper is required, even if the shaft is only 1-hour fire rated. So, in conclusion, you do need fire dampers if the duct is not enclosed in a fire rated shaft and penetrates one floor (but only one floor), and you do need fire dampers where the duct exits a rated shaft.

Fire Damper Testing Frequencies

Q: Our facility is a freestanding ambulatory surgical center and we only perform gastrointestinal (GI) procedures, not surgery. We lease a suite on the ground level in a 3 story building with multiple tenants. We had a state inspection recently and they asked us for documentation that we tested our fire and smoke dampers every 4 years. What are they looking for? We’ve been in the building for 13 years and no one has ever asked us about fire and smoke damper testing before.

A: Since it appears that the inspector is holding you accountable for compliance with the 2000 Life Safety Code, I will assume you need to comply with chapter 21, for existing ambulatory health care occupancies. Section requires compliance with section 9.2 which in turns requires compliance with NFPA 90A Standard for the Installation of Air-Conditioning and Ventilating Systems, 1999 edition. Section 3-4.7 of NFPA 90A requires the fire and smoke dampers to be tested once every 4 years. For clarification, CMS did issue an S&C memo on October 30, 2009 which permitted hospitals to change the frequency of fire and smoke damper testing to once every six (6) years, but this memo only applies to hospitals, and not to ambulatory health care occupancies. It is not unusual for authorities who inspect your building to fail to ask for certain documentation (such as test results of the fire/smoke dampers), and then at a later date, another authority will request that information. Just because the previous surveyors/inspectors did not ask to see this information, does not mean it was not required.  This inspector is now holding your organization accountable to what has always been a Life Safety Code requirement.

Smoke Dampers in HVAC Ductwork

Q: During a recent survey, we were cited by the surveyor for a 6 inch round duct that did not have a smoke damper installed where it penetrated a smoke compartment barrier, in an area of our hospital that is not protected with automatic sprinklers. I informed the surveyor that our local building code allows HVAC duct up to 6 inches diameter to penetrate a smoke compartment barrier and not be required to have a smoke damper. He did not accept that explanation and cited us anyway. I thought if one AHJ had an exception for a code requirement, then all AHJs had to accept that. What gives?

A: No, there is nothing that says one AHJ has to accept the decision of another AHJ, although they often do on a case-by-case basis. Besides, you are comparing apples to oranges here. The local building code probably does not recognize the NFPA LSC while the surveyor (if they were Joint Commission or CMS surveyors) only surveys you according to the LSC. You are required to comply with all local and state regulations, but when these regulations differ with the LSC, you have to comply with the most restrictive. In this case, section of the 2000 edition of the LSC requires compliance with section 9.2 which requires compliance with NFPA 90A Standard for the Installation of Air-Conditioning and Ventilation Systems (1999 edition). NFPA 90A does not have any exceptions for HVAC duct 6 inches or less in regards to requiring smoke dampers. You may be able to negotiate an agreement with the AHJ who cited you that you are in compliance with the local building codes, and see if they would accept that, but you would have to do this with every AHJ. The most practical thing to do is install smoke dampers in the 6 inch round ducts, or install sprinklers in the smoke compartments bordering this smoke barrier. According to section of the LSC, you are not required to have smoke dampers, but if you go this route, make sure your local building codes have the same exceptions.

Fire & Smoke Dampers No Longer Required

Q:  The hospital I work for recently completed its sprinkler upgrade and wants to reduce maintenance by removing some fire and smoke dampers in the walls.  What is the procedure for removing fire and smoke dampers within these walls? May we just permanently prop-open the wall dampers and leave them in place or should those dampers be removed since they no longer function as fire safety devices.

A: First let’s look at the requirement for smoke and fire dampers. NFPA 101-2000 LSC, section 9.2.1 requires HVAC ductwork to comply with NFPA 90A, which specifies when fire dampers are required. Generally speaking, fire dampers are only required in 2-hour fire rated walls or greater, or in any fire rated vertical shaft wall. They are not required in 1-hour fire rated walls with fully ducted systems on both sides of the rated wall, and they are not required in non-rated walls. Therefore, in this situation, it is permissible to remove them.

Section for existing construction (and section for new construction) has an exception that says smoke dampers are not required in smoke compartment barriers with fully ducted HVAC systems in smoke compartments protected with sprinklers. Therefore, it is permissible to remove smoke dampers from fully ducted HVAC systems in smoke compartments protected with sprinklers.

Your question asks what the procedure is to remove these dampers. It has always been my position to actually remove the dampers entirely and repair the ductwork. This would be considered “best practice” as it eliminates the dampers from being mistaken for devices that are supposed to work and be tested. However, many Authorities Having Jurisdiction (AHJ) will accept a damper that is no longer required to be in the wall, to be disabled and secured in the open position. If you choose to go this route, I would suggest you add a sticker on the outside of the damper identifying that it is no longer in service and is disabled.

Fire Dampers on Air Handlers

QUESTION: Are fire dampers required in ductwork when the duct penetrates the walls of the same room that house the air handler? These air handlers are equipped with duct detectors that shut the air handler system down and activate the alarm system.

ANSWER: It depends on the fire rating of the wall. NFPA 90A Standard for the Installation of Air-Conditioning and Ventilating Systems is very clear on this issue. Fire dampers are only required in the following situations:

  • When the duct penetrates a 2-hour fire rated barrier
  • When the duct penetrates any fire rated vertical shaft
  • When a duct terminates at a 1-hour (or greater) fire rated barrier but the airflow continues through the barrier into an open air plenum ceiling space

The need for a fire damper is a result of the fire rating of the wall. The room that you describe (air handler room) is not necessarily a hazardous room by definition, unless you also have fossil fuel-fired devices (gas-fired boilers, incinerators, water heaters, etc.). If the walls of this room are not required to be fire rated, then the ductwork does not require fire dampers.

Perhaps you are thinking about smoke dampers in regards to air handlers. Smoke damper are required to be installed in air handler systems that have a capacity greater than 15,000 cubic feet per minute. The purpose of these smoke dampers is to isolate the air-handling equipment, including the filters, from the remainder of the system in order to restrict the circulation of smoke. There are exceptions to this smoke damper requirement on air-handler units: A). on air handlers that are located on the floor that it serves and only serving that floor, and: B). When the air handler unit is mounted on the roof and only serves the floor immediately below the roof.

In these situations, the smoke dampers are not necessarily required to be mounted in the wall of the air-handler room, but just in the ductwork at the discharge of the air-handler. Remember: The purpose of the smoke dampers is to isolate the air-handling equipment from the remainder of the ductwork distribution system.