Maintaining reliability throughout the entire life cycle of a fire alarm system involves three distinct and equally important tasks which must be performed on a periodic basis: (1.) visual inspections, (2.) functional testing and (3.) maintenance activities. Many overlook the need to visually inspect the fire system and concentrate only on the functional testing of the components. However, each of these tasks are necessary and contribute to the assurance of a fire system that is ready to perform in the case of a fire.
Periodic Visual Inspections
A periodic inspection is a visual examination of the equipment to verify that nothing has changed from the initial design and installation that would affect its performance. Those charged with performing an inspection should be looking for a number of conditions which might affect the system’s ability to perform when called upon. A proper visual inspection should consider whether building modifications or occupancy changes would have an impact. A fire alarm strobe light designed and located to disperse light throughout an entire room may now be ineffective due to a reconfigured floor plan. Another important consideration is a change in environmental conditions. Increased cooling systems to support greater heat loads might be producing airflow rates impacting the need to adjust the design spacing of the ceiling smoke detectors. Building owners should also ensure that a visual inspection of the equipment includes identification of changes such as physical obstructions, device orientation, physical damage, degree of cleanliness and any other obvious problem that may not be indicated by the control panel automatically through electrical supervision. A minimum standard for these periodic visual inspections can be found in Table 14.3.1 Visual Inspection Frequencies of the National Fire Alarm and Signaling Code (NFPA 72).
Periodic Testing
Periodic testing is intended to validate the functionality of the fire protection system. Tests are performed by operating each component of the system to assure it performs as required in the case of an actual emergency event. A simple example of this sort of testing is to pull the lever of each Manual Fire Alarm Pull Station to ensure it performs as intended and initiates the required alarm condition. A proper testing program should also include testing the operation of all Emergency Control Functions in the system such as elevator recall or HVAC shutdown. NFPA 72, the National Fire Alarm and Signaling Code (2010 Edition), requires these functions to be tested at the same frequency as the device which initiates the action. For instance, if corridor smoke detectors activate the closure of fire doors, then this function must be tested annually to match the testing requirement of the smoke detector. Beyond just a simple functional test, the test method for many components may also involve the use of calibrated test equipment. One example of this is a duct smoke detector used to control the spread of harmful smoke. A proper test of this device not only must verify smoke will initiate an alarm, but also that the airstream of the ductwork is effectively being sampled. So in addition to the functional smoke entry test for the smoke detector, a pnumometer is used to measure the airflow from the sampling tube. This measurement is then compared to the acceptable range published in the manufacturer’s instructions to determine if the device is performing as designed. A minimum standard for these periodic tests can be found in Table 14.4.5 Testing Frequencies and Table 14.4.2.2 Test Methods of the National Fire Alarm and Signaling Code (NFPA 72).
Maintenance
Maintenance is the work necessary to keep the fire system operating properly. One form of maintenance is simply a response to a failure identified by a visual inspection or a test of the equipment. Service personnel should notify the system owner immediately whenever deficiencies are found during routine inspection and testing procedures. Considering the fact that life safety and/or mission continuity may be at risk, repairs should be made as soon as feasibly possible by qualified personnel. Whenever repairs are not made immediately, a temporary alternative means of protection should be put in place until the fire system is returned to an acceptable level of readiness. Another important form of maintenance is of a preventative nature. Many components in a fire protection system will require preventative maintenance at a prescribed frequency. These maintenance activities address components that degrade over time, have a finite lifespan or require periodic resetting or calibration. For example, most fire alarm systems utilize lead-acid type batteries as a secondary (backup) power supply. Although NFPA codes require routine testing to verify voltage levels are at an acceptable level, a preventative maintenance requirement exists requiring their replacement at 5 years from the date of manufacture. Another important preventative maintenance task involves regular cleaning of smoke detectors. Typically the detector manufacturer’s published instructions will provide both the recommended frequency and method for cleaning, but consideration should be given to adjusting these based on the environment where they are located.
In a survey conducted by the California State Board of Fire Services, building owners were asked about the current operational status of their fire systems and about the factors contributing to failures. 73% of the respondents cited a lack of maintenance as the cause for system failures. The truth is a proper inspection, testing and maintenance program will benefit not only in money savings over time, but even more importantly, will minimize an organization’s risk of liability.
1 Source: “Report to the Legislature in Response to House Resolution No. 14, Fire Alarm Systems,” December 30, 1983, Office of the State Fire Marshal, Sacramento, CA 95823.
When a building has a fire, its occupants rely upon the fire protection systems to perform successfully. However, all too often building owners are faced with the consequences of a fire system that has failed. What causes these failures? And what can be done to avoid another failure in the future? Having a suitable program of inspection, testing and maintenance (ITM) is one of the more important steps to be taken to assure the success of the fire protection system. The truth is, when an appropriate level of inspection, testing and maintenance is taking place, this activity will directly contribute to the high level of reliability expected of a fire protection system. But how does one determine just what is the “appropriate” level?
It all begins with having a proper understanding of the purpose of your ITM program. Its purpose is to discover failures of components that would prevent the fire system from operating as necessary during an emergency event. And of course, the goal is to discover and repair these failures prior to such an event. When developing a program, keep in mind that NFPA and other fire codes provide a minimum standard for ITM methods and frequencies. However, you may also want to consider other factors. For instance, a facility with increased risk or history of fires should consider more frequent intervals of testing or preventative maintenance. Also, a facility which supports mission-critical operations would require fire protection systems with a much higher degree of reliability than the average office building. Unfortunately, most building owners take a one-size-fits-all approach by allowing their decisions to be influenced only by the minimum requirements of the applicable fire code.
It is also important to remember that fire protection systems are the sum of many individual components, each one having the potential to fail. As you might expect, some components simply have the potential for a greater rate of failure than others. (For more on this topic, read my paper titled Inspection, Testing and Maintenance: A Window into System Reliability.) That’s why NFPA standards will prescribe a method and frequency of ITM for each individual component which is a part of the fire system. For instance, for a fire alarm system, the manual pull stations are required to be functionally tested annually, while the tamper devices supervising each sprinkler system valve must be tested semi-annually.
So, what’s the purpose of your ITM program? If it is simply to keep the Fire Marshall off your back, then you will most likely be focused on doing whatever the minimum requirements of the codes and standards. But hopefully your purpose is much greater than that and will be focused on achieving a highly reliable fire protection system, ready to respond when it is needed most.
ORR continues to grow its service footprint by expanding into our newest location, Las Vegas, Nevada. Since 2007, ORR’s west coast presence has grown beyond our expectation from Southern California, then in 2009 to Northern California and now to Nevada in 2012.
Randy Hardman, VP of the West Coast Region, was recently quoted saying, “ORR’s national customers have pushed us to expand our services to Nevada for nearly two years, but before we made the move, we felt we needed to walk before we could run. That required for us to make sure we had the right people in place with the support they need to ensure our customers received the quality of service and response times they have grown accustom to expect from ORR. I have been in the “Mission Critical Fire Protection Industry” for over 25 years and the last 5 years with ORR, but since coming to ORR, I have been amazed at the professionalism and technical knowledge they expect from their technicians. Simply put, that is why we delayed our move to Nevada. We believe, our patience to find the right experience technicians will prove to be our winning formula moving forward. So from all of us on the West Coast, we are truly excited about our move to Nevada, Here we GROW again!”
Fire Alarm, Detection, and/or Suppression System design, installation, emergency service or test and inspection services are just a phone call away for our newest Nevada location.
Phone: (877) 265-9705
e-Mail: lasvegas@orrprotection.com
Posted by
Lee Kaiser on Thu, Feb 02, 2012 @ 11:41 AM
Advances in computing technology, worldwide growth in data consumption, and the need for more efficient cooling of IT equipment is driving data centers to change rapidly. A significant part of these changes include the use of Hot Aisle or Cold Aisle (HACA) containment systems. The partitions that form these containment systems are affecting fire protection systems in these spaces. In the first part of this series of blog posts, I introduced how HACA systems are changing fire protection approaches in data centers. In this second part I will continue the discussion of how HACA systems are specifically challenging both fire detection and fire suppression systems in the Data Center.
Challenges to Fire Detection
The National Fire Alarm and Signaling Code (NFPA 72) gives guidance to engineers on the spacing of smoke detectors in rooms with different air change rates. The fire alarm code only provides data for smoke detector spacing in rooms up to 60 air changes per hour (ACH); this equates to data centers loaded to roughly 5 kW per rack. According to the Intel Corporation, HACA containment systems are implemented in data centers with densities of 12 kW per rack and higher. With cooling airflows sufficient for typical HACA cooling loads, air change rates within the contained aisles range from 500 to 1000 ACH and higher. These high airflows will challenge ceiling mounted spot smoke detectors due to the velocity of the air and dilution of smoke.
It has been common for fire protection engineers to specify air sampling smoke detection (ASSD) in rooms exceeding 60 ACH because of their increased sensitivity to smoke. Because of higher velocities experienced within contained aisles it makes even more sense to utilize ASSD. Engineers should consider installing ASSD sample pipes/ports arranged to sample the hot return/exhaust openings in the contained aisle. This would be done in the same manner as is commonly applied to traditional CRAC unit return air grilles.
Data center designers would do well to take notes on best practices of semiconductor manufacturing clean rooms where ASSD is often employed. Clean rooms have similar challenges of high velocities, turbulent air flows, and directional routing of air. There is an easy translation to data centers where air sampling detectors should be installed at the return air inlet to air handling units and somewhere immediately downstream of the hot side of the server at the ceiling level.
Despite the fact that more research is needed on how to detect fires in high airflow environments, many professionals believe that the detection techniques needed are already available to the industry.
Challenges to Fire Suppression
Whether the barriers included in HACA containment systems are applied horizontally, vertically or both, they can affect sprinkler pattern development and clean agent dispersion. NFPA 13: Standard for the Installation of Sprinkler Systems is very explicit in how to apply fire sprinklers to overcome obstructions in the protected space. These rules should be applied to sprinklers where HACA barriers exist in Data Centers. Many of these containment systems have provisions for “automatic” removal when a fire occurs; usually by means of a fusible link. For removal to work, the fire must grow to a point where it can melt the link(s). If the link that removes the barrier is not positioned perfectly over the location where the fire starts, the fire must grow larger to build heat in the location of the link. This also applies to systems that require fusing of multiple links for barrier removal. Be wary of containment systems that require a large fire to remove the barrier before the fire sprinkler system is given the opportunity to activate.
Plastic drop out ceiling panels, used most often in cold aisle containment systems, are another type of barrier that “automatically” removes. These panels are UL listed and melt around 135°F so that the sprinklers above the panels can operate. Data center managers should know that these panels are designed for use with standard response sprinklers that operate at a higher temperature near 155°F. Unfortunately, this sprinkler type is not installed in data centers; usually quick response sprinklers which fuse at 135°F are installed. The temperature difference is important and could lead to issues with sprinklers operating before these ceiling panels have dropped out. Installing quick response sprinklers inside the contained aisle may be the best way to avoid this issue.
In Data Centers protected by clean agent fire extinguishing systems, containment barriers must be removed prior to agent release. Containment systems which rely upon fusible action for removal are a problem because of the large fire size needed to obtain the action. Clean agent systems in data centers most often activate upon detection of smoke, not heat; and are designed to extinguished small developing fires. The problem of barrier removal can be overcome by adding extra clean agent nozzles within the contained aisle.
Clean agent nozzles have several of the same obstruction distance requirements as sprinklers. When retrofitting an existing Data Center with HACA containment, a qualified fire protection firm should be consulted to ensure the required extinguishing concentration can be obtained given the new barriers installed in the space.
It is a valid assumption that clean agents will disperse to spaces which are not in line-of-sight of the agent nozzle, such as the ability to reach the inside of server cabinets. The high airflows associated with containment systems challenges our current assumption and more research must be done on this topic.
While more research is needed to address these new challenges, one thing is for certain; hot aisle/cold aisle containment systems have the attention of data center managers, designers, and fire protection professionals. All are working to ensure a reliable means exists to detect and suppress fires in these environments. If you have added HACA to your data center and not had a qualified professional evaluate your fire protection system, you could be risking higher losses than what your business can tolerate. To learn more on this important topic, download my article that appeared in the 7×24 Exchange Fall 2011 Magazine.
Posted by
Lee Kaiser on Tue, Jan 31, 2012 @ 03:23 PM
Fire Protection System installations in Data Centers are being challenged by computing density increases and the push for PUE improvements. High cooling loads and reducing cooling energy cost is driving data center managers to change the physical structure of their rooms. Hot Aisle and Cold Aisle (HACA) containment systems in the various flavors they come in are very efficient at improving cooling efficiency and can often have short payback timeframes. Most newly constructed data centers these days include HACA containment and many existing data centers are being retrofitted as well. It is obvious that the HACA strategy is here to stay and for good reason.
HACA containment systems affect fire suppression and detection in many ways. They can make fires more difficult to detect and the obstructions they create can make them more difficult to control or extinguish. Those who have employed HACA strategies in their data center but have not made adjustments to the fire protection of the room will most likely have a problem and it may be bigger than they think.
This is the first of a two part series of blog posts describing how HACA systems affect conventional approaches to fire protection in the data center environment and considerations to make when designing a room with HACA systems. The truth is the fire protection community has not kept up with the pace of change in technology rooms. Often code development follows behind changes in technology. However, the good news is that experts within the fire protection industry are taking aim at this challenge today in order to develop guidance for the changing data center.
Common Misconceptions
There are two common misconceptions that lead some data center operators to ignore the impact of HACA containment on fire protection. The first misconception is that fires don’t happen in data centers, but the truth is they do. Businesses are often silent about fires in their IT facilities, in hopes of maintaining a positive image. Additionally many fires that do occur in these buildings are successfully controlled or extinguished by fixed fire suppression systems and are thus hardly newsworthy. These facts make it very difficult to monitor fire activity in data centers; yet we know they occur. Fire protection service organizations respond several times a year to re-arm suppression systems that discharged because of a fire. In the interest of client confidentiality these service providers do not share information about fires.
The second misconception is that the HACA containment system has features to address every possible fire protection issue. Manufacturers of containment systems are aware of the potential impact on fire protection and have often made assurances that their system will work with existing fire systems. Some of these claims are misleading and are result of an oversimplified understanding of how fire detection and suppression systems operate, rather than being based on solid fire science, experience and testing.
Containment Systems as New Barriers in the Data Center
When you start to break down the concepts employed by the various types of containment systems they are essentially barriers or new partitions within the space. These barriers serve to direct the cooling airflow to where it is needed most at the face of the computer server.
Many people assume that if a barrier added as part of a containment system is transparent, it will not affect the fire protection in the room. However, these barriers create three conditions that change the approach needed for fire protection in a medium to high density data center:
- The airflow pattern changes and disrupts the normal development of the smoke plume.
- The airflow velocity in the room increases within the contained aisle and can be a challenge for conventional means of smoke detection.
- The barriers act as obstructions to sprinkler spray patterns and clean agent suppression nozzles.
When thought of as barriers, the need for a professional analysis of the room’s fire detection and suppression system becomes well warranted.
In the second of this series of blog posts, I will discuss the challenges these containment barriers present to fire suppression and detection systems. I will also share about some of the progress being made by the fire protection industry to address the changing data center. To learn more on this important topic, download my article that appeared in the 7×24 Exchange Fall 2011 Magazine.
Locations, Dates and Registration
Building upon one of our most popular seminars from two years ago, we will share with you new fire protection trends and emerging technologies with the potential to have a significant impact on the industry; we call these “Fire Protection Game Changers 2.0.” Whether you are an engineer, facility manager, contractor or fire marshal, you will learn how these future trends and emerging technologies could change your approach to fire protection. Discover the advantages and disadvantages of these systems and in what applications they can be used to solve unique challenges.
What you will learn from the Experts:
Don’t be left behind. Join us for this revealing training program as we look to the future at these new trends and emerging technologies in fire protection:
- Discover what is happening with wireless fire alarm systems and how this technology can be a viable solution in particular applications.
- Learn about new technologies in air sampling smoke detection; what they are, how they work and in what new applications you may want to use them.
- Video Smoke Detection — discover where and when to use it.
Bonus Session:
Tips from the Insider… Inspection and Testing of your fire system
One of the most frequent questions we get is “How do I know my fire system is being inspected properly and meeting all fire code requirements?” We will share insider tips to give you the confidence that your valuable assets, personnel, and facilities are properly protected from the threat of fire.
Who should attend?
- Managers, facility directors and maintenance personnel who make fire protection decisions.
- Architects, engineers, designers, contractors, estimators and risk managers.
- AHJs, building inspectors, plan examiners, and fire marshals.
- Anyone who is responsible for critical fire protection decisions.
Online Registration
Seminar Brochure with Dates and Locations
ORR Protection Systems is excited to launch its new Fire Protection Blog to provide you with relevant information, real-time updates, NFPA Code changes and other important events taking place in the Fire Protection industry. It is our hope and desire that this blog becomes a reliable source for looking into that crystal ball of future trends and understanding the past.
Additionally, we also want to make it easy for you to connect with us through a variety of different channels like social media (LinkedIn, Twitter, Facebook, YouTube), online contact forms, email, and more.
Here’s what you can expect:
- Regular blog posts keeping you informed of “what’s happening” at ORR along with other relevant industry-related news.
- All the details on Fire Protection Educational Seminars, Lunch & Learn Programs and other industry educational opportunities.
- Videos, interviews, and other media that will help you get to know ORR on a more personal level.
- Other ways to connect with ORR online through links to our social media accounts.
- The opportunity to be become a subscriber and recieve announcements, seminar updates or an RSS feed of our regular blog posts.
- Easy-to-navigate pages and links to fire protection vendors.
- More online content for education and informational purposes.
Thanks for checking out our new blog. If you have questions or if there’s a certain topic you would like to see covered on our blog, you can submit a comment using our online form. Let us know what you think!