New Technologies Impacting Building Fire Safety & Construction

NCSBCS/AMCBO Public Sector Members Important Issues Call Summary
April 25, 2005

Mr. Cooper welcomed Dr. Grosshandler as guest speaker for this month’s call. He noted that Dr. Grosshandler would address recent research going on in the Fire Research Division at NIST that impact building fire safety. It was noted that everyone on the call should have received the background materials on the Fire Research Division that had been sent out along with the agenda for this call.

Dr. Grosshandler noted the research topics he would be covering. These would include items in early research stage and a long way off from adoption to items that are now in place.

Sensing Areas: NIST has been doing fire detection research since the early 1970’s. Now such detectors are inexpensive and everywhere. Fire, however, still kills 3,000 to 4,000 Americans each year, the majority of these deaths are in residential structures. Property damage, however, is still large in commercial & other occupancies.

Fire detection work at NIST has now shifted into looking at different and emerging technologies.

New Fire and Sensing Detectors: Thermal and rate of rise detectors and smoke detectors are all out there now. Optical sensors and ionization sensors work well. Smoke detectors respond quickly to small amounts of smoke, but it takes time for fire and smoke to migrate from source to the detector so you can’t guarantee that smoke detectors can detect the fire early in the event.

Line of sight or video (IR Sensors) work for large volume and, while they are much more expensive, you don’t need as many of them. Think there is a growing trend for greater use of video sensors since they are coupled with need for building security – thus giving you double use – also as a fire detector.

This approach is not perfect since you don’t have videos everywhere and you also have to have a sophisticated algorithm to query sensors about what they are seeing.

Combination Sensors: These have been in use for 10 years. They combine older technologies – both smoke and thermal sensors with rate of temperature rise and smoke particles. You can discriminate a fire from a nuisance source with these combination sensors. The objective here is to get away from false alarms that can be caused by such things as dust, lightening, welding, etc.

In wake of 9/11, you want to have a high level of confidence when you send equipment out.

Multi-gas sensors sensing smoke, CO, and carbon dioxide. As of today these are expensive and not giving a lot in benefit. These include pure IR sensors measuring hot gases.

Video based fire detection is still emerging. Combination sensors are growing in popularity.

Home Smoke Alarm Project at NIST: NIST did work on this during 2001-2003 and issued a report that is on the NIST website. The work was sponsored by several groups including USFA, NEMA, CPSC, and CDC. In the study, NIST looked at and compared technology between 1978 and 2002. Also looked at how fast sprinklers would respond and developments. Findings: existing technologies for smoke detection all work well.

An interesting finding in that project, however, was the increase during that time frame in the rapidity with which fires became untenable. In late 70’s, that rate was within 12 or 15 minutes after ignition; now that happens within 3 or 4 minutes. The difference is in the materials being used now versus in the ‘70’s that makes this a greater hazard now. The use of more plastics (as opposed to natural materials such as leather, wood, and wool) seems to create a greater flame spread problem.

This could be a problem in buildings in your state.

Question: Regarding ionization smoke detectors, is there a (radiation) hazard here?

Answer: Ionization detectors are definitely radioactive, but they have very minute amount, and there is no indication they are a health hazard. There could, however, further down the road be a small recycling problem.

Question: Rate of rise temp data, where is this available?

Answer: NIST has data and UL/ISO have standards covering this. The problem with detectors that are set to respond at too low of a threshold is that they can easily be set off by such things as an oven door opening, giving a false alarm. I suggest that if you are dealing with UL listed detector, you are o.k.

Approved Test Methods to Increase Immunity from Nuisance Sources: At NIST we have what we call a fire-emulator/detector-evaluator. Through it we do not need to run a full scale fire in a room. It is basically a wind tunnel device – generating smoke, water vapor, and CO2. We can produce simulated fires and can then query detectors.

Question: Is there any testing going on manufactured dust, magnesium, talcum, etc., that cause dust explosions and also give false alarms to detectors?

Answer: No, NIST has not undertaken any such tests but those areas would be worthy of a research in themselves.

Sensor-Rich Building Status Evaluation (and Prediction): If we have better sensors, then we can get a lot more data from buildings, a lot more than fire detection. Also can measure flow through the HVAC system, CO2, temperature in building, etc., to assure indoor air quality. If you link centrally all this information or can query them and move information to a central repository, then we can learn a lot more about the building and what’s going on. For example, if there is a fire in room, is the smoke detector working right? Sensors in the thermostat then can help.

Sensor networks also can help you monitor the progress of a fire in a building. That can be very useful to the fire department when they arrive. Such networks can tell them how fast fire is spreading and how best to approach the fire before going inside. Such information also can help people in building as to which stairwells to exit from (coolest and no or less smoke). All this could be very helpful for both occupants and first responders.

Within NIST we are now working on the following areas:

* We are taking sensor data (fire/hvac) and feeding that data into an inverse fire prediction model to predict what fire will do next to help fire fighters. We are not quite there to make those calculations, but we are close. This will help you compare strategies as roll-up on the event. A real time aid is decades off but could be used earlier for training purposes. More computing power on laptop makes this practical.

In trying this out with the (R.I.) Station Nightclub fire, it took us a week of real time to compute, so we have ways to go.

* Virtual Cybernetic Test Bed – We take data from the controller within building and the test bed lets us play around with different scenarios. Could go in through a company such as Honeywell and can test products online to see how control system interacts with fire detection systems.

This system will ultimately provide data to building operators and first responders. It also will help with purchasing and design decisions.

* Structural collapse indicators – So far there is nothing better than actual experts on structural collapse. We are doing research in NIST on a structural collapse sensor used on dams to see if can be applied to buildings. We have done a test with a shopping mall, residence (wood & masonry structures). If we put a sensor in right place on the outside of a building, we can get a signal on the fact that the building might let go or change its structural integrity. This kind of sensor will need to be very sophisticated and give real data. It would be attached when the first responders roll-up on a disaster site.

Initially such sensors will be easier to include in new building construction when the building goes up. California in particular has seismic areas where this can be used to help them evaluate a pending structural collapse.

Question: Regarding these calculations, how long would it take to do those?

Answer: A fire dynamic simulator is being used. For input to it, we need: the geometry of the building, then we put in common fuel (furnishings are the largest component of this), and how the fire starts, then the computer model predicts what happens next - growth, smoke, what happens if you open a door or break window, etc. Output is graphics animation of fire and how it grows. The goal here is to help people see how these grow.

This is on the NIST website if you want to look at it. (Note: All NIST website addresses are found at the end of this summary.)

Question: Is anything being done to make elevators so they can be used as a means of egress? We have 1920 vintage buildings (in our city) where this could be key to reusing them.

Answer: Elevator use is a high priority area. This includes use by fire services, disabled, and general occupants

Firefighter lift is the first priority. NIST is working with the ASME 17 Committee on this. Most of our work is to help assure that standards are written properly.

Comment: For elevator retrofit, access to occupants is a big issue in Richmond.

Answer: The technology exists in this area, but it is expensive. One of the retrofit issues is that we don’t want water in hoist-way to short out the motor. Cost and clever design are important issues here as well as the liability for developers and elevator companies.

NIST is moving in the area of retrofit and industry is working on this as well. ASME and fire protection engineers are working on this.

Believe in future elevators will play a more important role. In WTC #2 thousands of lives were saved because they evacuated early using them. Need to make sure they are hardened. It can be done, but it definitely is a matter of economics.

Fire Suppression: NIST has been looking at alternatives to halon suppression systems. There really are alternates but none so far are as good as halon. For each of the currently available alternatives, you need more storage areas for the materials. We have been looking at this for 12 years or so.

Overall, sprinklers really work. Watermist systems do a better job protecting gas turbines than do regular sprinklers.

Sprinklers in certain circumstances can be used in computer rooms. (Caution - you need to consult a fire protection engineer for this though.)

Hybrid SYSTEMS are being used. These have an airbag-type gas generator and use it to pressurize a powdered or gaseous agent to put out fire.

Flame Retardant Polymers: NIST is working to finding alternative to brominated fire retardant materials. Right now, this is a very tough area in which to make progress. Remember that the label, "flame retardant" doesn’t mean the material won’t burn. It will burn at certain temperatures. So far we have not yet found a way to make foam furnishings really fire-safe. This is an important area of NIST and national research.

Fire Resistance Test Methods & Test Rating Systems: Clearer definitions of fire resistance are needed. Need to find appropriate ways to evaluate new technologies to determine if they are an improvement over existing methods especially over the life cycle.

Fire Resistive Steels & Coatings for Steel: Research also needs to be done here to find a way to determine how fire resistive coatings will perform 20 years down the road. We don’t have a method for that yet but are looking into it.

Technologies for Building Operations in CBR Attacks: NIST in this area is looking at where things go inside the building. We need to be able to predict where CBR (Chemical, Biological, Radiological) material will move in a building to help us develop different mitigation and or evacuation strategies. For example, if there is a release outside of a building and the building can shut vents, we need to be able to evaluate and predict which vents should be shut and for how long.

NIST was involved in the Hart Senate Building anthrax case and helped in the clean up efforts.

Cost Effective Risk Management Tools: This is an important area in homeland security and one where we have been working with other federal agencies to develop tools to help building owners. For example, if you are a building owner or a facility manager and need to invest in new technology to mitigate terrorist attack, these tools walk you through the process of determining what technologies or mitigation strategies will work and also provide you with a life cycle cost analysis in applying them. Some of these tools have already been developed while others are still being worked on.

Closing & List of NIST Websites: At this point in time, noting that the call had run through its established one hour time frame, Mr. Cooper asked if there were any more questions for Dr. Grosshandler. There were none.

Mr. Cooper and those on the call thanked Dr. Grosshandler for his presentation. Dr. Grosshandler said he was pleased to participate and that he would forward to NCSBCS a list of NIST websites where participants and NCSBCS and AMCBO members could go for more information on a number of the topics he had covered.

Those sites are as follows:

http://www.bfrl.nist.gov (Building and Fire Research Lab homepage.)

http://www.bfrl.nist.gov/fris (Fire Research Information Service – provides access to entire library.)

http://www.fire.gov (Quarterly newsletter highlighting new technologies, aimed primarily at fire services.)

Mr. Wible thanked everyone who participated and reminded them that the next joint NCSBCS/AMCBO Public Sector Members Important Issues Call would be held on Monday, May 16 at Noon EDST. The guest speaker for that call will be Dr. Shyam Sunder, NIST’s Acting Deputy Director of the Building and Fire Research Laboratory and Lead Investigator of the Federal Buildings and Fire Safety Investigation of the World Trade Center Disaster.

Dr. Sunder will speak on the status of that investigation including the reports that NIST issued on it on March 31, 2005 (See NCSBCS/AMCBO Monthly Members e-Bulletin for April for more details on that report.)

At 1:10 p.m. the call was adjourned.