Summary: Examining the complicated nature of fire safety systems necessitates a thorough comprehension of pertinent building regulations and standards. Let’s cover many aspects of fire safety in this comprehensive guide, addressing important issues and offering perceptive solutions based on NFPA guidelines and building code requirements.

Here are the highlights of the importance of quarterly inspections, starting with the importance of automatic ball drips as described in NFPA 24. The complexities of trapeze hangers for several pipes are then discussed, emphasizing the significance of following NFPA 13 recommendations for appropriate stability and support.

Also the significance of listed air compressors in fire sprinkler systems, explaining impending modifications to NFPA 13 that will take effect in 2025. Then investigate how adding auxiliary dry systems affects hydraulic calculations and the identification of full design areas.

To determine if interior hoses should be taken into account when calculating sprinkler systems, further investigation must examine the relationship between fire pump systems and standpipes. Also evaluate a 24-inch-deep steel beam’s suitability as a draft curtain using NFPA 13 guidelines. Follow-through with the NFPA 25 criteria is crucial because of frozen fire sprinkler systems and the requirement for pipe labeling.  It also discusses how to secure outside openings and where to put stage hose valves in accordance with construction requirements.

Let’s seek to provide clarity and insight into fire protection systems, concluding with an assessment of the fire-resistance capabilities of fire sprinkler water curtains and their compliance with fire rating criteria. Through answering all of the questions, readers have the ability to understand legal requirements and guarantee the highest level of safety in construction environments.

1. Ball Drip. Description- NFPA 24 allows for automatic ball drips to be buried and released into crushed gravel. NFPA 25 requires that the ball drip be examined quarterly. Question 1. If a ball drip cannot be seen during an NFPA 25 inspection, should it be recorded as a deficiency?

Answer: Failure to complete an NFPA 25 inspection or test does not constitute a violation of the standard. A deficit is an identifiable fault in a component or system. Failure to conduct inspections or tests does not establish a deficiency. The AHJ can enforce fire code requirements, which negligence may violate.

Automatic drain valves were allowed to be buried until the 2016 edition of NFPA 13.

Section of NFPA 13 requires automatic drain valves to be fitted in a way that allows for inspection and testing in accordance with NFPA 25. Previous NFPA 13 editions lacked clear guidelines for routine inspection and testing of drain valves. NFPA 25 does not establish inspection techniques for buried drain valves. When a hidden drain valve is not accessible for quarterly inspection, the operation is delayed until the FDC pipework hydrostatic test is due. If the buried drain valve fails, excavation and repair are essential. To ensure good access to the drain valve, consider installing a road box or other alternate means.

2. Trapeze Hangers and Multiple Pipes. Description- To estimate the size of hanger rods for many pipes in a trapeze configuration, consider the weight of the pipes, the distance between hangers, and the rods' load-bearing capacity to ensure sufficient support and stability. Question 2. When creating trapeze hangers for many pipes, how should the hanger rod size be determined?

Answer: To construct trapeze hangers to suspend several pipes, use NFPA 13, 2010 edition, Chapter 9 for establishing the proper hanger rod size. NFPA 13 recommends installing a single sprinkler pipe per trapeze hanger, rather than numerous pipes.

NFPA 13 does not clearly prohibit suspending numerous pipes from a trapeze hanger. Alternate hanger options are permissible under NFPA 13 Section, but an engineer with certification must review and approve them. This comprises designing and certifying the hanger assembly to meet the performance standards outlined in Section

3. Listed Air Compressor. Description- The issue is whether a regulatory body or organisation needs to list or certify an air compressor. Question 3. Do we need a listed air compressor?

Answer: No, the NFPA 13, 2013 version does not require a listed air compressor. According to Section, components including drain piping, valves, and indicators that have no direct impact on system functioning are not required to be specified. Air compressors in dry pipe systems are excluded from this exemption since poor operation has no substantial impact on sprinkler discharge.

However, it is worth mentioning that a modification is coming in the 2025 version of NFPA 13. Section 7.10 in the 2025 edition requires the listing of air compressors used for fire prevention in sprinkler systems. This shift emphasizes the importance of air compressors in system performance and attempts to assure longevity and reliability by adhering to accepted product standards.

Although the 2025 version of NFPA 13 has not yet been approved, it is important to be aware of the upcoming need for listed air compressors. Installing a listed air compressor is recommended to meet future standards and optimize system performance, however it is not essential at this time.

4. Auxiliary Dry System. Description- The concern is whether an extra 950 square feet from a nearby wet system should be included in the overall distant area calculation, or if the 1,000 square feet for the dry system is adequate. This consideration is made in the context of an expansion with a distinct room that has doors, most frequently to determine adequate fire protection coverage or system needs. Question 4. If an auxiliary dry system is fed by a wet system to feed a minor buildout of 1,000 square feet, do we need to include an extra 950 square feet from the nearby wet system to compute the complete distant area, or can we just calculate the 1,000 square feet for the dry system? The expansion has a separate room with doors.

Answer: NFPA 13, 2016 edition, Sections,, and require that hydraulic calculations for the density/area technique include all necessary changes for the whole design area.

Instead, consider using the room design method. For this situation, the dry pipe system room must be rated as described in Section, with openings covered as per Section According to Section, water supply needs for sprinklers should be based on the room with the highest demand if it meets the required rating and protection standards. Section recommends focusing calculations on the most hydraulically demanding rooms and communication spaces when using the room design method.

5. Inside Hose Stream for Sprinklers. Description- The question at issue is whether the inside hose should be included in sprinkler system calculations when a fire pump powers both a standpipe and a sprinkler system that are not interconnected. This question is most likely about evaluating the sprinkler system's hydraulic demand and capacity needs as part of fire prevention planning. Question 5. A fire pump powers a standpipe and a sprinkler system. They are distinct systems, not integrated. Do we include the inside hose in sprinkler system calculations?

Answer: When a fire pump serves separate sprinkler and standpipe systems, it is not necessary to include inside hose stream demand in sprinkler system estimates. If inside hoses are connected to the sprinkler system as described in Section 16.15, the inside hose stream demand must be considered. When the AHJ orders it, NFPA 13 permits the addition of minor mop-up hose connections to sprinkler systems. This requires the insertion of an inside hose. The sprinkler system connected to a standpipe system does not account for hose stream requirements. NFPA 13 and NFPA 14 allow for autonomous system design.

While drawing water from the public water supply, which the fire department also uses, Table mandates total hose stream demand on the fire pump suction side. If the fire pump is running on a tank or raw water source, hose stream demand is optional.

6. Solid Beam as a Curtain. Description- The issue asks whether a 24-inch-deep steel beam meets the requirements of NFPA 13-2016 edition Section 11.1.2(2) for use as a draft curtain/stop for surrounding dangers. This will most likely include determining if the beam's dimensions and material qualities are adequate for successfully controlling fire or smoke in compliance with fire protection requirements. Question 6. Can a 24-inch-deep steel beam be used as a draft curtain/stop for nearby risks, as per NFPA 13-2016 edition Section 11.1.2(2)?

Answer: The 2016 edition of NFPA 13, Section 11.1.2(2 and 3), recommends using draft curtains to cover nearby risks. A 24-inch steel beam can meet the standard’s “physical separation” requirements. Authorities with jurisdiction (AHJ) may impose further precautions for corrugations on the deck. Some AHJs may need rockwool to fill void spaces in corrugated steel floors/roofs that sit on top of beams. The standard’s parenthetical remark #2 underlines the need for the beam to delay heat in one location while avoiding sprinkler fusion in another. NFPA 13 does not specifically address the stuffing of corrugated voids; hence, it may fall outside the scope of this section.

7. Pipe Labelling. Description- The issue is whether NFPA 13 mandates the use of tags or labels other than those that the manufacturer provides. This entails identifying whether additional labeling requirements exist for pipes in fire prevention systems in order to assure compliance with safety standards and ease correct maintenance and identification. Question 7. Is it required by NFPA 13 to label pipes with tags or labels other than those specified by the manufacturer?

Answer:  NFPA 13 requires pipe labelling, however, the procedure depends on the manufacturer’s manufacturing standards (see Table 6.4.1). Section 6.3.11 of NFPA 13 specifies labelling requirements for installed pipes, including visibility and marking criteria.

The National Fire Sprinkler Association (NFSA) does not have any manufacturing guidelines that mandate using additional tags or labels in addition to those that the fabrication shop has already installed. Additional tags or labels can be removed once the plumbing is installed.

8. Main Drain and Hydraulic Calculations. Description- The topic investigates the viability of employing a main drain test for hydraulic calculations in buildings without pumps or with extreme cold temperatures that impede flow experiments. It discusses different approaches for evaluating the hydraulic performance of fire protection systems in such situations, taking into account aspects such as equipment availability and environmental limits. Question 8. Can a main drain test be utilised for hydraulic calculations in buildings without pumps or too cold for flow tests?

Answer: The flow rate of a system cannot be accurately determined using main drain test findings, according to established standards. Discharge line roughness and drain diameter utilisation for water outflow are two factors that affect this limitation.

Some suggest placing a pitot gauge in the drain outlet to convert velocity pressure values to flow rates. However, this approach does not provide correct flow calculations. The formula for translating velocity pressure to flow implies complete utilisation of the outlet diameter, which is not always accomplished with drain pipes.

As a result, it would produce inaccurate flow conversions. The 2-inch drain test confirms the water supply integrity and ensures system valves are open after the previous test.

The main drain test ensures that the valves connecting the water supply and sprinkler system are open. Opening the main drain connection consistently during each test compares residual water supply pressure to earlier tests, identifying potential faults such as closed valves or choked pipes.

9. System Status after Freezing. Description- The question asks whether NFPA 25 contains criteria for testing or replacing a frozen fire sprinkler system. It tries to discover whether the NFPA 25 standard has any specific guidelines or methods for dealing with frozen fire sprinkler systems, such as testing techniques or system replacement requirements. Question 9. Does NFPA 25 provide standards for testing or replacing a frozen fire sprinkler system?

Answer: NFPA 25 does not provide explicit rules for dealing with frozen fire sprinkler systems.

However, the following actions are advised as best practices:

  1. Make sure the system is thoroughly thawed.
  2. Inspect sprinklers, pipelines, fittings, and components to ensure proper operation.
  3. Replace any broken parts or components.
  4. Air test the system; if no leaks are found, perform a hydrostatic test per NFPA 13.
  5. If leaks are discovered, patch them and repeat the air test until all are rectified before performing the hydrostatic test as per NFPA 13 standards.

Consult the local authority having jurisdiction (AHJ) for additional requirements and guidance.

These guidelines are not mandatory under NFPA 25 or NFSA. These are options for repairing frozen pipes; however, other ways may also be considered.

10. Exterior Opening Protection. Description- The question is whether the second-floor canopy's exterior entrance has to be shielded. It requests clarity on whether protective measures are required for the canopy's external aperture in order to prevent environmental elements or risks from impacting the structure or its inhabitants. Question 10. Is it necessary to shield the exterior aperture of the second-floor canopy?

Answer: The ceiling is flammable, and the canopy is not sprinklered due to its size (less than 4 feet). If we have to install dry pendent sprinkler heads, that will be an issue. Please view the accompanying snippets for further details.

We do not have enough information to determine whether sprinkler protection is necessary in this location. You mentioned that the ceiling is flammable. However, no information is provided on whether the projection or overhang is built of combustible or non-combustible materials. The combustible vs. non-combustible issue determines the applicable section of NFPA 13. Section may be applicable if the building materials are combustible and the exposed finish surface has minimal combustibility.

Insufficient information prevents us from determining if Section applies. Based on the photograph, it appears that the space at the forefront is an outside projection. Other locations may qualify as overhangs and must adhere to Section standards. NFPA 13’s exterior projection regulations, as well as sections on soffits, eaves, and overhangs, may apply to this case.

11. Stage Hose Valves. Description- The topic is whether NFPA or other standards specify the required distance or side for class 2 hose valves on each side of the stage, as outlined in Sections 905.3.4 and 905.3.4.1 of the 2022 California Building Code (CBC). This question most likely wants clarity on the location restrictions for hose valves in regard to stage areas under fire safety regulations. Question 11. The 2022 California Building Code (CBC), Sections 905.3.4 and 905.3.4.1: The CBC refers to class 2 hose valves on each side of the stage. Is there a reference in NFPA or other standards indicating the required distance or side?

Answer: The 2022 CBC, Sections 905.3.4 & 905.3.4.1, require Class II hose valves on both sides of the stage. The CBC enforces this site requirement, however, installation guidelines are provided by relevant standards. Neither NFPA 13 nor NFPA 14 have specific regulations for hose hookups on stages.

According to the CBC 2022 edition, stages larger than 1,000 square feet require a Class III standpipe on each side that meets NFPA 14 installation criteria.

Automatic fire sprinkler systems require only 1 1/2-inch hose connections. To install 1 1/2-inch hose connections on sprinkler systems, see NFPA 13 (2019 edition), Section 16.15.

The exemption in Section 905.3.4 specifies that hose connections must be accessible to reach all sections of the stage with 100 feet of hose and 30 feet of spray (total of 130 feet). The CBC allows for distances to exceed these limitations with approval from the AHJ.

Hose stations are designed to be used by trained occupants to control incipient flames on stage.

Some jurisdictions may omit this requirement for stages, as the International Fire Code and NFPA 1 Fire Code allow for the removal of fire hose and nozzles from 1 1/2-inch hose connections (Class II) with AHJ permission.

12. Water Curtain. Description- The inquiry asks if a fire sprinkler water curtain can offer a one-hour fire rating. It aims to determine the fire-resistance characteristics of such curtains and whether they meet the duration criteria for fire protection in building codes or standards. Question 12. Can a fire sprinkler water curtain offer a 1-hour fire rating?

Answer: No. Building a fire-rated assembly does not require a fire sprinkler system.

The building code requires fire-resistant assemblies to be tested using ASTM E119 standards. This standard specifies the materials needed for various fire ratings, including 1-hour, 2-hour, and 3-hour assemblies. ASTM E119 testing confirms that a single layer of 5/8 inch Type X gypsum board can withstand a 1-hour fire. Sprinklers may reduce the fire resistive rating, but they do not ensure a 1-hour or 2-hour fire rating for a barrier or wall.

Listed window sprinklers offer up to two hours of glazing protection. Section 703.4 of the International Building Code (IBC) allows for this exception, which differs from fire-resistant assemblies.

Courtesy: Roland Asp, CET, TechNotes