Sprinkler Obstructions and Discharge Patterns

photo source: pmengineer.com

Important to fire sprinkler effectiveness is sprinkler discharge pattern development. A fire sprinkler system should be designed in a manner that provides full water coverage from the fire sprinkler system. Inherent building construction or design elements can pose potential obstructions to the full coverage or discharge pattern of the sprinkler system.  However, these buildings and elements must still be protected. NFPA 13, Standard for the Installation of Sprinkler Systems, provides sprinkler coverage guidance for these obstructed areas.

To determine the proper application it must first be determined if the construction is obstructed or unobstructed.  Then it must be determined if the obstruction is continuous or noncontinuous.

Is this obstructed or unobstructed construction?

To be considered obstructed, the construction elements must be composed of “beams, trusses, or other members” that will impede heat flow, water distribution, or otherwise affect the ability of the sprinkler to control or suppress the fire. [13:3.7.1]

Construction types that may create obstructions, include:

• Beam and girder
• Concrete Tee
• Composite wood joist
• Panel construction
• Bar joist with fireproofing
• Steel purlin

Unobstructed construction includes any “beams, trusses, or other members” that do not impede heat flow, water distribution or the ability of the fire sprinkler to control or suppress fire. This generally consists of construction members that are not solid.[13:3.7.2]

Unobstructed construction elements may include:

• Bar joist
• Open-grid ceilings
• Smooth ceilings
• Standard mill (heavy timber)

Is the obstruction continuous or noncontinuous?

If the obstruction affects the sprinkler discharge pattern of two or more adjacent sprinklers then the obstruction is considered to be continuous. However, if only one sprinkler discharge pattern is affected then the obstruction is noncontinuous.

Different sprinkler head types and orientations have different requirements for designing to protect obstructed areas.  These are addressed in the following sections of NFPA 13.

• General guidance: 13:8.5.5
• Pendant and upright sprinklers: 13:8.6.5
• Sidewall sprinklers: 13:8.7.5
• ESFR sprinklers: 13:8.12.5

A great reference tool for quickly determining the design criteria and requirements for obstructed areas is this ceiling obstructions reference tool/calculator provided by Meyer Fire.

The Standpipe Kit

photo source: highriseoperations.com

High-rise building fires can be the most challenging and dangerous operation for a firefighter. An important element for success in high-rise fire incidents is "the standpipe kit".  These kits include all the essential tools a crew may need to conduct standpipe operations. In the article titled, "The Standpipe Kit", published in WNYF (2nd/2015), describes the components that make up a functional kit. This article serves as a useful guide for creating or updating your department's own kit.

The basic standpipe kit should include:

• Door chocks and wedges (assorted)
• Spanner wrenches (2)
• Off-set pipe wrench (18" minimum) - to remove caps or operate stripped control valves
• Control valve wheels - various sizes, as needed for the response area
• Wire brush
• Pressure gauge or standpipe flowmeter 
• Nozzle (spare)
• Adapters and couplings (various)
• Gate valve

This list presents basic items that should be included in every kit.  Pre-fire planning for your response area must be conducted. Based on the pre-fire plans other adapters, thread types, sizes, or items may be needed and should be added to the kit. 

Quantified Assessment of Options

The second trait in Paul Bryant’s, 7 Traits of Highly Effective Fire Engineers, is “being objective”.  Successful fire protection professionals make decisions based on facts, even if these facts contradict personal experiences or beliefs. To reduce the level of subjectivity in the selection of fire protection solutions, Bryant provides a table he refers to as the “quantified assessment of options”.

This table bases fire protection system selection on three factors: performance, logistics, and economics. Performance describes how a system will perform within a specific environment.  Logistics refers to the practical application of system installation and maintenance. The economic factor addresses the life cost of the system.

Each system or technology option will be scored on these three factors. Each of these scores will be multiplied and a total score provided. The total score should provide a clear path for the best choice of system or technology to be used.

The table template is as follows:

*the number scale may be project specific as differing projects may weigh one factor more than another

Here is a sample issue addressed utilizing the table:

 

This table and the “quantitative assessment of options” process will help to avoid pre-judgement and base systems and technologies on their pure merits.

Reading Meyer Fire? You Must!

If you're not already reading Meyer Fire (www.meyerfire.com), you need to start immediately!  Meyer Fire is the independent resource for fire protection professionals.  Meyer Fire creates resources for the Fire Protection P.E. exam.  The Meyer Fire site produces a weekly blog post and a daily fire protection question. Additionally, the site offers tools and resources including calculators, articles, and a job board.

Here are 10 must-read posts to get you started:

1. Advantages of Return Bends in Fire Sprinkler Systems
2. Slope Requirements for Fire Sprinkler Pipe
3. Breakout of a Floor Control Riser Assembly
4. Sprinkler Ceiling Obstructions
5. Solving Noise from Dry-System Compressors
6. Components of a Fire Sprinkler
7. Sprinkler Design for Elevators
8. New Occupant Load Factors Coming to NFPA 101
9. Details and Requirements of the Inspector's Test
10. The Other (Easy) Way to Space a Smoke Detector

An awesome "added value" feature of these posts is the hand drawn (by Joseph Meyer) fire protection system components (such as the one below)!

Making CRR Work for Your Department

"Firefighter" by Justin Hoffman

Since, 1830 when James Braidwood penned one of the earliest guides “on the causes of fires, and the means of preventing them”, fire departments have been practicing some form of community risk reduction. With the modern standards of NFPA 1730, NFPA 1452, and NFPA 1300, fire prevention organizations now have a reference tool and clear guidance on how to best conduct community risk reduction activities prevent fire, preserve life, and protect their communities.

Over the last few months, several posts have been published as a resource for CRR activities:

• Engaging Firefighters in Community Risk Reduction
• Conducting Home Visits
• Home Fire Extinguisher FAQ
• Preventing Fires in the Wildland/Urban Interface (WUI)

Presented below, as a sort-of  end cap to this series of posts, are some general tips and items to be considered before leaving the firehouse and engaging in CRR activities.

• Dress professionally in a uniform that clearly identifies you with your department
• Ensure a full supply of resources and handouts are available
• Work only in teams, of at least two people.
• Remember the primary goal of the CRR “mission” is to eliminate hazards to life and property. Be able to clearly articulate this to your community.

Florida Fire Prevention Code, 6th Edition

January 1, 2018 marked the effective date of the 6th edition of the Florida Fire Prevention Code. The Florida Fire Prevention Code is composed of the 2015 editions of NFPA 1, Fire Code and NFPA 101, Life Safety Code, with Florida specific amendments.

These Florida state specific amendments, local amendments, informal interpretations, past editions, and future notices can be accessed from the Florida Fire Prevention Code page, from the Division of State Fire Marshal. 

The full list of adopted codes, standards, and referenced documents and editions are listed in FAC 69A-60.005.

Douglas True, Fire Prevention at Dade City, has built an amazing set of plan review spreadsheets based on this latest edition of the FFPC. These sheets include plans review checklists and calculations.  This document can be downloaded here, http://bit.ly/FFPC_plansreview.

Florida Fire Prevention Code, 6th Edition can be purchased from BNi Building News.

Horse Sense Fire Protection

In 2017 we saw more headlines related to horse fire deaths than ever before, here are a few:

• 18 horses die in Plainfield barn fire
• 24 horses killed at equestrian training barn fire in Connecticut
• 6 horses killed in Monticello boarding stable fire
• 23 horses killed in Limestone County barn fire
• 13 horses killed in Western Michigan barn fire

What can we do to prevent future barn fire incidents and protect these animals?

NFPA 150, Standard on Fire and Life Safety in Animal Housing Facilities, classifies horse barns as a Class 1 facility, “an area of a building housing animals with no general public access”. Horses are categorized as a Category B animal, which includes “all agricultural animals”, with special requirements.

To fully protect the barn property and animal life, the following fire protection code requirements must be in place.

• Fire Alarm System
• Under 3,000 sq. ft. - alarm not required
• 3,000 - 20,000 sq. ft. - local alarm only required
• 20,000+ sq. ft. - monitored alarm required
• Fire Extinguisher
• Minimum 2A:10BC located within 50 ft. travel distance
• Lightning Protection
• Required to be installed in accordance with NFPA 780.
• Fire Sprinkler System
• Sprinklers required throughout
• NFPA 13 system
• Smoke Control System
• Required, may be modified by AHJ
• NFPA 92
• Operating Features
• Disaster/emergency management plan required
• Drills (on the disaster/emergency plan) to be conducted annually
• Training on use of fire extinguishers

For more information on barn fire prevention and safety visit these sites:

FireSafetyInBarns.com

TheHorse.com - Barn Fire Prevention

FEMA - Animals in Disasters

Related Posts:

Protecting Your Pets - Understanding NFPA 150

How to House a Tyrannosaurus Rex

WNYF - Four Articles of Impact from 2017

WNYF - With New York Firefighters is the official training publication of the FDNY. This publication should be required reading for any fire service professionals that are serious about their job, careers, and professional development. The quality, relevance, and applicability of the articles is first-rate.  The magazine is zero advertising, no frills, all training content.  The featured fire calls, recurring columns, and FDNY section profiles, provide administrative and operational insight that can be applied to your own operation.

The magazine is published in digital and print formats. Two additional publications, ProEMS and ProFIT, address the EMS component of the FDNY and the fire department’s strict commitment to physical well being.  They also produce a podcast, films, and other books. At only $25 a year (4 quarterly issues), this is the most efficient cost to benefit expenditure that an individual or department can spend.  To subscribe or receive more information go to, FDNYpro.org.

4 Articles of Impact from 2017:

Manhole Fires by Asst. Chief Paul Cresci, Chief of Safety (WNYF 1st/2017)

A primary hazard with manhole fires can include active electricity, carbon monoxide, and natural gas. This article outlines the precautions to be taken, and guidance for incident stabilization and fire extinguishment. The FDNY utilizes the dry chemical agent, FireIce, at manhole fires involving electrical cables (Class C fires).

How the Safety Command Conducts Investigations, Part I and II by Batt. Chief Joseph McHugh (WNYF 2nd/2017 and 3rd/2017)

The Safety Command is tasked with conducting all investigations into major apparatus accidents and serious injury or fatality to a member. Part I of this article series outlines the four responsibilities of the Safety Command team in the event of an incident.  These responsibilities include: 1) preserving the scene, 2) preserving evidence, 3) conducting interviews, 4) writing the report. Part II of this series focuses on the specific aspects of an apparatus accident investigation.

Blue Roofs: Features and Collapse Risk at Fire Operations by Asst. Chief Ronald R. Spadafora, Chief of Fire Prevention (WNYF 3rd/2017)

Many firefighters may be familiar with green construction and green roofs, but less may be familiar with the blue roof.  The blue roof is a non-vegetated, sustainable system, designed to temporarily store rainfall in order to control and regulate drainage of water from a roof. This article identifies the components and construction features of these roof types and addresses response considerations and collapse concerns.

Roll Call: The Firefighters Competitive Advantage by Batt. Chief Frank Leeb (WNYF 4th/2017)

The roll call is the first meeting of the morning and provides the earliest and best opportunity to gain a competitive advantage. This is the time to honor the past, exchange information, and prepare for the shift ahead. This article serves as a reminder of the importance of being intentional during the roll call time, and its critical role in the shift day.