FM Global Data Sheet 2-0: Practical Design Guide for Automatic Sprinkler Systems
Loss Prevention Recommendations for Automatic Sprinkler Systems
FM Global Data Sheet 2-0 provides engineering recommendations for the installation and performance of automatic sprinkler systems to minimize property loss and ensure reliable fire protection.
This guide presents a practical design approach for engineers, translating FM requirements into step-by-step design considerations, system selection criteria, hydraulic principles, and installation best practices.
Scope and Engineering Intent
FM Global Data Sheet 2-0 focuses on the installation and system performance requirements of automatic sprinkler systems.
Rather than providing occupancy-specific density criteria, the document emphasizes proper system configuration, component reliability, and overall installation quality to ensure effective fire control and property protection.
From a practical engineering perspective, the guidance primarily addresses:
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Proper selection and arrangement of sprinkler system components
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Structural support and piping installation practices
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System response performance considerations
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Discharge effectiveness and obstruction evaluation
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Documentation expectations for insurance review
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System verification and acceptance testing procedures
Limitations of FM 2-0
The document does not replace occupancy-specific design criteria and should be used in conjunction with other relevant FM data sheets addressing:
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Hazard classification and design densities
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Underground fire mains and water supply systems
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Seismic protection requirements
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Corrosion prevention
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Long-term inspection and maintenance procedures
FM Global 2-0 vs NFPA 13 – Key Engineering Differences
While both FM Global Data Sheet 2-0 and NFPA 13 address automatic sprinkler system installation, their design objectives and enforcement philosophies differ significantly.
NFPA 13 is primarily a minimum installation standard adopted by authorities having jurisdiction (AHJs) to establish baseline fire protection requirements for life safety and property protection.
FM Global 2-0, on the other hand, reflects an insurance-driven loss prevention approach, emphasizing system reliability, performance under adverse conditions, and reduction of business interruption risk.
When designing for an FM-insured facility, engineers should not assume NFPA compliance automatically satisfies FM requirements. Additional evaluation of system configuration, performance reliability, and risk mitigation measures is often necessary.
From a practical design standpoint, engineers must recognize that NFPA 13 compliance does not automatically ensure FM Global acceptance. When working on FM-insured facilities, it is essential to evaluate system configuration, hydraulic performance, water supply reliability, and installation practices beyond minimum code compliance.
A competent fire protection engineer should be capable of identifying when additional performance considerations are necessary and adapting the design accordingly.
Practical Design Navigation Workflow (FM 2-0 Interpretation)
Step 1: Identify the Occupancy and Hazard Classification
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Determine the type of facility (industrial, storage, commercial, etc.)
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Refer to the relevant FM occupancy-specific data sheet for density and sprinkler criteria
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Confirm whether any occupancy-specific recommendations override general installation guidance
Step 2: Confirm Extent of Sprinkler Protection
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Verify whether full building protection is required
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Identify any exceptions or special conditions
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Confirm any requirements related to “non-room” spaces or concealed areas
Step 3: Establish Water Supply Reliability
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Evaluate available water source
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Confirm capacity, duration, and redundancy
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Assess whether additional reliability measures are required
Step 4: Select Appropriate System Type
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Wet system (standard ambient conditions)
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Dry system (low temperature environments)
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Preaction (sensitive occupancies)
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Refrigerated-area systems (very low temperatures)
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Deluge systems (special hazards)
Step 5: Evaluate System Performance Parameters
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Water delivery performance
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System size limitations
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Piping configuration
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Sprinkler arrangement and spacing
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Obstruction analysis
Step 6: Address Special Conditions
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Storage protection considerations
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Ceiling configuration and slope
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Obstructions affecting discharge
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Special protection scenarios
Step 7: Documentation and Plan Review Preparation
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Prepare hydraulic calculations
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Verify component specifications
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Confirm drawing compliance
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Ensure readiness for insurance review
Step 8: Acceptance and Verification
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System testing procedures
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Performance validation
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Inspection readiness
Areas Requiring Sprinkler Protection
Extent of Sprinkler Protection
From an FM engineering perspective, sprinkler protection is generally expected throughout the building to minimize fire spread and reduce potential property loss.
Full protection philosophy means that all areas presenting a fire risk should be evaluated for sprinkler coverage unless a justified exception applies.
Exceptions to Full Protection
In certain limited situations, sprinkler protection may not be required in portions of a building where:
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The construction is noncombustible, and
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The occupancy does not introduce combustible hazards.
However, such determinations should be made carefully and in alignment with overall project risk expectations.
Use of Occupancy-Specific Criteria
Design densities, hose stream allowances, and sprinkler operating duration are typically governed by occupancy-specific guidance rather than general installation provisions.
Engineers should always verify whether project-specific occupancy requirements modify or override general installation recommendations.
Fixed Special Suppression Systems
Alternative fire suppression systems (such as clean agent or oxygen-reduction systems) are not automatically considered substitutes for automatic sprinkler protection unless explicitly permitted by the applicable project criteria.
Sprinkler protection remains the primary fire control strategy in most FM-driven facilities.
Water Supply Requirements for FM Sprinkler Systems
Reliable water supply is a fundamental requirement in FM-driven sprinkler system design. The system must be supported by at least one dependable water source capable of delivering the required flow, pressure, and duration based on the applicable occupancy hazard.
Unlike minimum code compliance approaches, FM emphasizes not only hydraulic adequacy but also supply reliability under adverse conditions.
Key Engineering Considerations
When evaluating water supply for an FM project, engineers should verify:
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Total sprinkler demand (ceiling and in-rack, where applicable)
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Hose stream allowance
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Required discharge duration
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Pressure adequacy at the most remote point
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Overall system reliability
Water supply must support the full design basis established by the relevant occupancy-specific guidance.
Underground Fire Mains and Piping Network
The fire water distribution network should be designed and arranged to ensure dependable delivery to the sprinkler system.
Engineers must evaluate:
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Underground main sizing
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Looping vs. dead-end configurations
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Isolation valve placement
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System redundancy
Reference to project-specific fire main design criteria is essential when determining network configuration.
Tanks, Reservoirs, and Pumps
Depending on project conditions, water supply may involve:
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On-site storage tanks
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Public mains
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Fire pumps
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Reservoir systems
Engineers should ensure compatibility between supply type and required system performance.
Domestic Water Connections
Where sprinkler systems share water sources with domestic systems, proper safeguards must be in place to prevent impairment of fire protection performance. Alarm monitoring and supervised connections are critical considerations in shared supply arrangements.
Flushing of Underground Mains
Before placing the sprinkler system into service, underground piping must be thoroughly flushed to remove debris and obstructions that could impair sprinkler operation.
From an engineering standpoint:
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Flushing velocity should be sufficient to remove construction debris.
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Flushing flow should not be less than the system’s calculated demand.
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Where direct full-system flushing is impractical, sectional flushing may be necessary.
The objective is to achieve adequate internal pipe cleanliness before system commissioning.
Engineering Insight – Why FM Emphasizes Flushing
Inadequate flushing of underground piping is a common cause of system impairment due to debris obstruction at sprinkler orifices. FM-driven projects place strong emphasis on pre-commissioning cleanliness to ensure reliable discharge during fire events.
Flushing Velocity Requirement for Underground Mains
FM recommends flushing underground fire mains at a velocity sufficient to remove debris prior to commissioning. As a general engineering principle, this requires high-velocity flow through hydrants or flushing outlets to achieve effective internal pipe cleaning.
The flushing flow should be capable of producing a velocity in the main that ensures removal of construction debris and foreign material before placing the system into service.
For pipe-size-specific flushing flow requirements, refer to the official FM Global Data Sheet 2-0 - Table 2.1.3.5 (Page 11)
FM Requirements for Sprinkler System Components
In FM-insured facilities, sprinkler system components must align with FM Global approval and loss prevention expectations. Component selection is not based solely on general fire protection suitability, but on compliance with FM-specific criteria.
Use of FM Approved Equipment
Where FM Approval exists for a product category, components should be FM Approved for the intended application.
Engineers must verify approval status through the appropriate FM approval listings and ensure that the selected product is permitted for the specific system type and occupancy hazard.
Application and Compliance Review
Each component should be evaluated against:
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Its FM Approval listing and limitations of use
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Manufacturer installation requirements
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Applicable FM occupancy-specific data sheets
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Project-specific or insurer requirements
FM projects require confirmation that components are not only listed, but correctly applied within their approved scope.
Compatibility and Environmental Suitability
Sprinkler system components must be compatible with:
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Maximum anticipated system pressure
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Minimum and maximum ambient temperatures
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Environmental exposure conditions
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Interaction with other FM-approved components
Improper compatibility can compromise system performance and may not meet FM review expectations.
Typical Components Evaluated Under FM 2-0
FM 2-0 installation guidance generally applies to the following sprinkler system elements:
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Automatic sprinklers
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System control and alarm valves
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Backflow and check valves
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Waterflow monitoring devices
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Test and inspection connections
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Pressure monitoring instruments
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Fire department connections
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Drain and pressure control devices
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Sprinkler piping and fittings
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Pipe supports, hangers, and bracing assemblies
Component configuration must align with FM installation philosophy and system performance requirements.
Engineering Insight – FM Review Expectations
In FM-driven projects, the review process often evaluates not only whether components are approved, but whether they are correctly selected for the specific hazard, environmental conditions, and system configuration. Proper documentation of approval status is typically expected during plan review.
🔥 Top 10 FM Global Sprinkler Design Mistakes Engineers Make
FM-insured projects demand more than basic code compliance. Many sprinkler systems that comply with NFPA 13 still receive review comments under FM Global standards due to performance, reliability, or configuration concerns.
Below are the most common design mistakes observed in FM-driven projects.
1️⃣ Assuming NFPA Compliance Equals FM Compliance
Many engineers complete hydraulic calculations per NFPA 13 and assume the system will satisfy FM review.
FM often evaluates:
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Delivery time performance
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System size limitations
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Component approval status
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Water supply reliability
NFPA compliance alone is not sufficient.
2️⃣ Ignoring Water Delivery Time in Dry and Preaction Systems
Hydraulic balance does not guarantee acceptable water delivery performance.
FM projects frequently require validation of maximum water delivery time, especially for:
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Dry systems
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Preaction systems
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Refrigerated-area systems
Failure to evaluate this early can result in redesign.
3️⃣ Using Non-FM Approved Components
Specifying UL-listed components without verifying FM Approval can trigger review comments.
FM-insured projects typically expect:
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FM Approved sprinklers
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FM Approved valves
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FM Approved fire pumps
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FM Approved detection components (where applicable)
Always verify approval listings before final specification.
4️⃣ Oversizing Sprinkler Systems
Large system areas increase:
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Delivery time
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Pressure loss
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Reliability risk
FM may limit system size depending on configuration and performance criteria.
5️⃣ Incorrect Hazen-Williams C-Value Assumptions
Using standard NFPA roughness factors without considering:
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System type
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Pipe material
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Gaseous medium (air vs nitrogen)
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Environmental conditions
can result in non-conservative hydraulic calculations.
6️⃣ Inadequate Flushing Provisions
Failure to provide proper flushing connections for underground mains and branch lines can result in debris obstruction and rejection during commissioning review.
FM emphasizes effective pre-service flushing.
7️⃣ Poor Evaluation of Concealed Spaces
Engineers often ignore:
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Combustible concealed spaces
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Duct interiors
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Mechanical voids
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Cooling tower structures
FM requires evaluation of fire spread potential in non-room areas.
8️⃣ Improper Ceiling and In-Rack System Coordination
Storage occupancies require careful coordination between:
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Ceiling-level sprinklers
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In-rack sprinklers
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Control valves
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Water supply capacity
Improper coordination can compromise system effectiveness.
9️⃣ Overlooking Environmental Compatibility
Corrosive environments, cold storage, or high-temperature areas require material compatibility review.
Improper pipe selection or component rating can reduce system reliability.
🔟 Incomplete Documentation for FM Review
Common documentation gaps include:
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Missing hydraulic summary sheets
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No delivery time validation
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Missing component approval verification
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Incomplete water supply information
FM review is documentation-driven. Clear and complete submissions reduce delays.
🎯 Engineering Takeaway
FM design is not just about meeting density and pressure requirements. It is about ensuring reliable system performance under real fire conditions while minimizing business interruption risk.
Engineers who understand this philosophy early in the design process avoid costly redesigns and review delays.
🔥 FM Global vs NFPA 13 – Practical Design Conflicts Engineers Must Understand
Although FM Global standards and NFPA 13 both address automatic sprinkler systems, conflicts can arise when a project must satisfy both regulatory approval and FM insurance requirements.
Understanding where differences occur helps engineers avoid redesign, delays, and costly corrections.
1️⃣ Minimum Code vs Performance-Based Loss Prevention
NFPA 13
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Establishes minimum enforceable installation requirements
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Adopted by Authorities Having Jurisdiction (AHJ)
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Focused on life safety and basic property protection
FM Global
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Insurance-driven loss prevention standard
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Emphasizes system reliability and reduced business interruption
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May require enhanced performance beyond minimum code
🔎 Practical Conflict:
A system approved by AHJ under NFPA may still require modification to satisfy FM review.
2️⃣ Water Delivery Time Requirements
NFPA primarily focuses on hydraulic density and operating area.
FM places additional emphasis on limiting maximum water delivery time, particularly for:
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Dry systems
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Preaction systems
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Refrigerated-area systems
🔎 Practical Conflict:
A hydraulically balanced dry system may still fail FM review if delivery time exceeds performance expectations.
3️⃣ System Size and Area Limitations
NFPA allows system sizes within code-defined parameters.
FM may restrict system size based on:
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Performance reliability
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Water delivery capability
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Configuration type
🔎 Practical Conflict:
Large dry systems acceptable under NFPA may require subdivision for FM compliance.
4️⃣ Component Approval Requirements
NFPA permits listed equipment from recognized testing laboratories.
FM-insured projects typically expect FM Approved components where available.
🔎 Practical Conflict:
UL-listed equipment may satisfy NFPA but trigger comments during FM review if not FM Approved.
5️⃣ Pipe Roughness (C-Value) Assumptions
NFPA provides typical C-value guidance.
FM differentiates hydraulic assumptions depending on:
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System type
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Pipe material
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Internal environment
🔎 Practical Conflict:
Using standard NFPA C-values in dry systems may result in non-conservative FM calculations.
6️⃣ Concealed Space Protection
NFPA includes defined exceptions for certain concealed spaces.
FM may require additional evaluation where combustible loading or fire spread potential exists.
🔎 Practical Conflict:
Spaces omitted under NFPA allowances may require protection under FM expectations.
7️⃣ Ceiling and In-Rack Coordination
NFPA storage chapters provide prescriptive criteria.
FM emphasizes system coordination, reliability, and performance validation between:
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Ceiling sprinklers
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In-rack sprinklers
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Water supply capacity
🔎 Practical Conflict:
Design that meets NFPA storage density may require re-evaluation under FM performance considerations.
8️⃣ Gaseous Medium in Dry and Preaction Systems
NFPA allows compressed air.
FM may emphasize inert gas systems for corrosion control and reliability.
🔎 Practical Conflict:
Air-only systems may require additional justification or modification in FM-insured facilities.
9️⃣ Detection and Activation Logic
NFPA provides guidance on detection-based activation for preaction and deluge systems.
FM closely evaluates:
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Detector type
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Spacing
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Environmental suitability
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Release panel compatibility
🔎 Practical Conflict:
Detector spacing compliant with NFPA may not align with FM activation expectations.
🔟 Documentation Expectations
NFPA plan approval typically focuses on code compliance.
FM review often requires:
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Detailed hydraulic summaries
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Component approval verification
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Delivery time validation
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System configuration review
🔎 Practical Conflict:
Incomplete documentation can delay FM acceptance even if the design is technically adequate.
🎯 When FM Overrides NFPA in Practice
In FM-insured facilities, insurance requirements often govern final system configuration, even if local code approval is already obtained.
The prudent approach is to:
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Identify early whether the facility is FM insured.
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Apply occupancy-specific FM guidance during concept design.
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Validate delivery performance before finalizing layout.
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Coordinate with FM reviewer proactively.
🔥 Engineering Insight
FM does not exist to contradict NFPA.
It exists to reduce financial loss and business interruption.
Engineers who understand both frameworks can design systems that satisfy regulatory authorities and insurance reviewers simultaneously.
🔥 FM Plan Review Checklist for Engineers
(Practical Guide for FM-Insured Sprinkler Projects)
FM Global review is performance-driven and documentation-focused.
A hydraulically correct system can still receive review comments if configuration, approval status, or delivery validation is incomplete.
Use the checklist below before submitting your sprinkler design for FM review.
✅ 1️⃣ Confirm Occupancy-Specific Design Basis
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Identify the applicable FM occupancy-specific data sheet
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Verify design density and operating area
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Confirm hose stream allowance
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Confirm required system duration
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Check if specific sprinkler system type is mandated
🔎 Common mistake: Designing from NFPA hazard classification instead of FM occupancy guidance.
✅ 2️⃣ Verify System Type Selection
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Wet, dry, preaction, refrigerated-area, vacuum, or deluge?
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Does the occupancy require a specific type?
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Are environmental conditions properly evaluated?
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Is freeze protection addressed?
🔎 Common mistake: Selecting dry systems without evaluating delivery time impact.
✅ 3️⃣ Validate Water Delivery Time (Where Applicable)
For dry, preaction, refrigerated-area, vacuum, and some deluge systems:
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Has maximum water delivery time been calculated?
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Is piping volume appropriate?
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Is system size within acceptable limits?
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Is water supply adequate to support required performance?
🔎 Common mistake: Ignoring delivery time until after layout is finalized.
✅ 4️⃣ Confirm Hydraulic Calculation Assumptions
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Correct density and area used?
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Proper hose stream allowance included?
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Correct C-values based on system type and pipe material?
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Remote area located correctly?
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Pressure losses conservatively estimated?
🔎 Common mistake: Using default NFPA C-values in FM dry systems.
✅ 5️⃣ Check Component Approval Status
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Are sprinklers FM Approved?
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Are valves FM Approved?
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Are fire pumps FM Approved?
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Are detection and release panels compatible and approved?
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Is documentation available to verify approvals?
🔎 Common mistake: Using UL-listed components where FM Approval exists.
✅ 6️⃣ Evaluate System Size and Configuration
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Is the sprinkler system area within acceptable limits?
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Is piping arranged to support required performance?
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Is the system single-path where required?
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Are control valves accessible and supervised?
🔎 Common mistake: Oversized dry systems causing delivery time failure.
✅ 7️⃣ Review Ceiling and In-Rack Coordination (If Storage)
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Are ceiling and rack systems separated where required?
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Is water supply capable of supporting combined demand?
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Are control valves properly arranged?
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Are sprinkler types coordinated with storage hazard?
🔎 Common mistake: Ceiling system designed without validating in-rack performance impact.
✅ 8️⃣ Confirm Flushing Provisions
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Are underground mains arranged for effective flushing?
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Are branch lines flushable?
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Are flushing connections accessible?
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Has debris removal been considered in commissioning plan?
🔎 Common mistake: No practical flushing method for branch lines.
✅ 9️⃣ Verify Freeze and Mechanical Protection
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Are valves protected from mechanical damage?
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Are dry/preaction systems protected from freeze?
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Is piping protected from impact in storage areas?
🔎 Common mistake: Mechanical damage risk not evaluated.
✅ 🔟 Review Detection and Activation (If Preaction/Deluge)
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Is detection type appropriate?
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Is spacing consistent with approval listing?
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Are panels compatible with sprinkler system type?
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Is backup power capacity adequate?
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Is single or double interlock correctly configured?
🔎 Common mistake: Detection spacing copied from NFPA without FM validation.
✅ 1️⃣1️⃣ Documentation Completeness Check
Before submission, confirm that the following are included:
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Hydraulic calculation summary
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Water supply information
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System configuration drawings
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Component approval documentation
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Delivery time validation (if required)
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Design basis narrative
🔎 Common mistake: Submitting drawings without a clear design narrative.
🎯 Final Engineering Reminder
FM review is not only about compliance —
It is about reliability and risk reduction.
Ask yourself before submission:
"If a fire occurs under worst-case conditions, will this system perform reliably and quickly?"
That mindset aligns with FM philosophy.
🔥 How to Reduce Water Delivery Time in Dry Sprinkler Systems
(FM-Focused Engineering Guide)
Water delivery time is one of the most critical performance factors in FM-insured dry sprinkler systems. Even when hydraulic calculations meet density and pressure requirements, excessive delivery time can lead to FM review comments or required redesign.
Below are practical engineering strategies to reduce delivery time and improve system performance.
🔷 Why Water Delivery Time Matters
In dry systems:
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Piping contains air or inert gas under pressure.
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Upon sprinkler activation, air must first be released.
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Water then travels from the riser to the operating sprinkler.
Longer piping volume and complex layouts increase delay.
FM emphasizes limiting delivery time to ensure rapid fire control and reduced property damage.
✅ 1️⃣ Reduce System Size
Smaller dry systems generally:
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Contain less air volume
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Drain faster
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Fill faster
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Deliver water sooner
Engineering Tip:
Instead of one large dry system, consider dividing into multiple smaller zones where practical.
✅ 2️⃣ Minimize Piping Volume
Delivery time is directly affected by total internal pipe volume.
Ways to reduce volume:
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Avoid unnecessary loops and grids (where not required)
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Optimize main sizes
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Avoid oversized piping
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Eliminate dead legs
The less air volume, the faster water arrives.
✅ 3️⃣ Use Proper Pipe Sizing Strategy
Oversized pipe increases air volume and slows water arrival.
Design strategy:
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Size mains efficiently
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Avoid excessive upsizing for future expansion
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Confirm hydraulic necessity before increasing diameter
Balanced pipe sizing improves both hydraulics and delivery time.
✅ 4️⃣ Consider Inert Gas Systems
Nitrogen-inerted systems can:
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Reduce corrosion
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Improve long-term internal pipe condition
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Maintain more stable internal pressure
While this does not directly shorten delivery time, it improves long-term reliability and consistency.
✅ 5️⃣ Maintain Adequate Water Supply Pressure
Higher available pressure at the riser:
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Increases water acceleration
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Improves system fill time
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Reduces delivery delay
Evaluate pump sizing and water supply margin early in design.
✅ 6️⃣ Optimize Valve and Riser Arrangement
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Position risers centrally where possible
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Minimize excessive branch run lengths
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Avoid complex routing
Shorter travel paths improve response performance.
✅ 7️⃣ Verify Compressor Sizing
In dry systems using air:
-
Excessive air pressure increases release time
-
Undersized air compressors may cause unstable pressure
Maintain appropriate supervisory pressure levels to avoid unnecessary delay.
✅ 8️⃣ Avoid Excessive System Height Differences
Vertical elevation differences increase time required for water to reach uppermost sprinklers.
Consider zoning tall buildings appropriately.
✅ 9️⃣ Validate Early – Don’t Wait for Review
Perform delivery time evaluation during preliminary layout — not after final drawings are complete.
Redesigning a dry system late in the project is expensive and time-consuming.
🔟 Coordinate With Occupancy Requirements
Some occupancies impose stricter performance expectations.
Storage and refrigerated facilities require particular attention.
Always confirm occupancy-specific performance criteria before finalizing layout.
🎯 Common Design Mistake
Engineers often focus only on hydraulic balance (density and pressure), ignoring:
-
Air volume
-
System geometry
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Piping configuration
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Delivery path efficiency
Hydraulically correct does not automatically mean performance compliant.
🧠 Engineering Insight
Reducing water delivery time is not just about pipe sizing —
it is about system configuration strategy.
Designing for performance from the start prevents FM review delays and costly revisions.
🔥 FM Global Sprinkler Design – Step-by-Step Workflow for Engineers
(Practical Application Guide Based on FM 2-0 Philosophy)
Designing for FM-insured facilities requires more than meeting minimum code. It demands a structured, performance-oriented approach focused on reliability, rapid fire control, and business continuity.
Below is a practical step-by-step workflow engineers can follow when designing sprinkler systems for FM projects.
🔷 STEP 1 – Confirm FM Insurance Status Early
Before beginning design:
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Confirm whether the facility is FM insured
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Identify the client’s FM contact or risk engineer
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Determine if a formal FM review will be required
⚠ Many redesign issues occur because FM involvement is identified late.
🔷 STEP 2 – Identify the Applicable Occupancy Data Sheet
FM design begins with occupancy classification.
-
Determine hazard type (industrial, storage, process, etc.)
-
Identify the applicable FM occupancy-specific data sheet
-
Confirm density, duration, and hose stream basis
Design criteria must originate from the occupancy sheet — not NFPA hazard classification.
🔷 STEP 3 – Select the Appropriate Sprinkler System Type
Evaluate:
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Ambient temperature conditions
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Freeze risk
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Sensitivity of protected contents
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Ceiling configuration
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Storage characteristics
Choose among:
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Wet
-
Dry
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Preaction
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Refrigerated-area
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Vacuum
-
Deluge
Confirm whether the occupancy sheet mandates a specific system type.
🔷 STEP 4 – Establish Reliable Water Supply
Confirm:
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Available flow and pressure
-
Required discharge duration
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Pump requirement (if applicable)
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Redundancy expectations
-
Supply reliability
FM places strong emphasis on dependable water supply under adverse conditions.
🔷 STEP 5 – Develop Preliminary System Layout
While drafting layout:
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Evaluate system zoning
-
Consider system size limits
-
Minimize piping volume in dry systems
-
Position risers strategically
-
Assess ceiling and rack coordination
Avoid designing one oversized system for convenience.
🔷 STEP 6 – Perform Hydraulic Calculations Using FM Criteria
Ensure:
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Correct density and area
-
Proper hose allowance
-
Appropriate C-values
-
Accurate remote area selection
-
Conservative pressure assumptions
Hydraulic adequacy must align with FM occupancy guidance.
🔷 STEP 7 – Evaluate Water Delivery Performance (If Applicable)
For dry, preaction, refrigerated, vacuum, and some deluge systems:
-
Validate maximum delivery time
-
Confirm system configuration supports required performance
-
Adjust pipe volume or zoning if needed
Do not finalize drawings before confirming delivery performance.
🔷 STEP 8 – Verify FM Approval of Components
Confirm FM Approval status for:
-
Sprinklers
-
Valves
-
Fire pumps
-
Detection panels
-
Release devices
Document approval listings before submission.
🔷 STEP 9 – Address Special Conditions
Evaluate:
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Concealed spaces
-
Combustible voids
-
Corrosive environments
-
Freeze protection
-
Mechanical damage exposure
-
In-rack protection (if storage)
These are frequent FM review comment areas.
🔷 STEP 10 – Arrange for Flushing and Maintenance Accessibility
Ensure:
-
Underground mains are flushable
-
Branch lines can be cleaned
-
Control valves are accessible
-
Inspection and test connections are properly located
FM emphasizes long-term reliability, not just initial installation.
🔷 STEP 11 – Prepare Complete Documentation Package
Before submission:
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Hydraulic summary
-
Water supply curve
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Delivery time validation (if required)
-
Component approval documentation
-
Design basis narrative
-
System layout drawings
Clear documentation reduces review cycles.
🔷 STEP 12 – Conduct Internal FM Compliance Review
Before submission, ask:
-
Does the system meet occupancy criteria?
-
Is delivery time validated?
-
Are components FM Approved?
-
Is system size appropriate?
-
Are concealed spaces addressed?
A structured internal check avoids external comments.
🎯 Engineering Philosophy Summary
FM design is built on three core principles:
1️⃣ Reliable activation
2️⃣ Rapid water delivery
3️⃣ Sustained performance
Everything in FM sprinkler design supports these goals.
🔥 Professional Disclaimer
This content provides independent engineering interpretation and practical guidance related to FM Global sprinkler system requirements. It does not reproduce or replace official FM Global publications. For complete and current requirements, refer to FM Global Data Sheets.