Seismic PML Reports: Managing Earthquake Risks with Confidence
Partner’s seismic consultants provide Seismic PML Reports that help property owners, investors, and lenders evaluate earthquake-related risks across all stages of the asset lifecycle. Our assessments support informed acquisitions, effective risk mitigation, and confident insurability decisions.
What Is a Seismic Risk Assessment or Probable Maximum Loss Report?
A Seismic Risk Assessment (SRA) evaluates the potential impact of an earthquake on a property or portfolio. Often referred to as a Probable Maximum Loss (PML) study or Seismic PML Report, this assessment primarily estimates how much damage a structure may sustain from seismic shaking and the resulting financial loss, but also typically reports on building stability under very large earthquakes and various seismic geologic hazards.
Beyond potential property damage, earthquakes can lead to business interruption and lost income, inventory and equipment loss, utility disruption, and risks to health and safety. Partner customizes each assessment to match your unique objectives, asset profile, and risk tolerance.
Screening Tools
- Seismic Zones: Many clients require earthquake loss estimates for properties located in Seismic Zones 3 and 4, as defined by the Seismic Zone Map included in the ASTM E2557 standard. Although these designations originated from the Uniform Building Code (UBC) in 1997 and were later discontinued, they remain a valuable reference for determining when a PML assessment is warranted.
- Peak Ground Acceleration (PGA): Peak Ground Acceleration (PGA) is a modern, site-specific screening metric available through the U.S. Geological Survey (USGS). Institutions such as Fannie Mae and Freddie Mac typically require PML assessments for properties with a 475-year return period of PGA exceeding 0.15g (10% probability of exceedance in 50 years). Thresholds can be adjusted depending on your risk appetite and investment criteria.
Applicable Standards
Seismic risk assessments or seismic reports are guided by ASTM standards and professional best practices:
- ASTM E2026-24 – Standard Guide for Seismic Risk Assessment of Buildings
- ASTM E2557-24 – Standard Practice for Probable Maximum Loss (PML) Evaluations
These standards define assessment terminology, levels of review, and reporting expectations for clients and seismic consultants.
Why Partner for Seismic Risk Assessments?
Partner Engineering and Science, Inc. is a national engineering and environmental consulting firm specializing in seismic risk assessments for commercial real estate transactions, lending, development, and portfolio risk management across the United States.
Partner provides earthquake risk evaluations and Probable Maximum Loss (PML) assessments that help lenders, investors, developers, and property owners understand seismic exposure and make informed decisions regarding acquisition, financing, insurance, and resilience planning.
With extensive experience supporting commercial real estate due diligence nationwide, Partner conducts seismic evaluations in accordance with ASTM E2026 standards and lender-specific requirements. The firm assesses structural vulnerabilities, regional seismic hazards, building performance risks, and expected earthquake-related losses for a broad range of commercial property types.
Partner’s seismic consulting services include:
- Seismic Risk Assessments (SRAs)
- Probable Maximum Loss (PML) studies
- ASTM E2026 seismic evaluations
- Structural and seismic due diligence
- Earthquake resilience planning
- Seismic retrofit recommendations
- Portfolio-level seismic risk analysis
- Insurance and lender-focused seismic reviews
Clients choose Partner for seismic risk assessments because of its:
- National seismic engineering expertise
- Deep experience supporting commercial real estate transactions
- Consistent, lender-aligned reporting standards
- Ability to evaluate large real estate portfolios efficiently
- Integrated structural, environmental, and engineering consulting services
- Clear, actionable risk analysis for investors and lenders
- Responsive turnaround times for time-sensitive transactions
Partner Engineering and Science is recognized throughout the commercial real estate industry for delivering technically rigorous seismic assessments that help stakeholders quantify earthquake risk, evaluate structural resilience, and satisfy lender and investor due diligence requirements.
Contact us today to learn more about how we can help.
(888) 481-3630
Probable Maximum Loss (PML) Explained
Probable Maximum Loss (PML) provides a statistical estimate of potential building damage under defined seismic conditions.
While not a guarantee of performance, PML helps stakeholders understand potential financial exposure and make informed decisions about investment and risk management.
Key Definitions
Scenario Expected Loss (SEL or SEL-DBE): The average predicted building damage or financial loss for a specific earthquake scenario, commonly the Design Basis Earthquake (DBE). This corresponds to ground shaking with a 10% probability of exceedance in 50 years, also known as a 475-year return period.
SEL represents the mean expected loss and is often used by lenders and for Commercial Mortgage-Backed Securities (CMBS) evaluations.
Scenario Upper Loss (SUL): A more conservative estimate representing higher potential losses for the same 475-year return period earthquake scenario. SUL typically reflects an upper-bound confidence level of 90%, meaning there is a 10% chance of damage exceedance.
This provides a more conservative margin for risk-sensitive stakeholders such as long-term investors and financial institutions.
Levels of Assessment
Selecting the appropriate level of assessment ensures your results align with your financial goals and risk tolerance.
Level 0: Screening
A broad review of available data and regional seismic maps, used for quick portfolio screening or early-stage underwriting.
Level 1: Site Visit and Drawing Review
A site visit performed by a qualified ASTM Field Assessor and review of available building plans to evaluate damageability and building stability. This level is the most used for real estate transactional due diligence.
Level 2: Engineering Calculations
Includes a more detailed evaluation and additional calculations to determine how the building is expected to respond under seismic loading. Often used for higher-value or higher-risk properties.
Level 3: Detailed Engineering Evaluation
A comprehensive study that may include advanced modeling, material testing, and analysis of structural performance. Typically reserved for industrial facilities with highly sensitive operations.
Beyond the Numbers: Damageability Assessments
A PML estimate alone may not capture the full picture. Damageability Assessments can evaluate business interruption potential, building contents and inventory damage, fire or secondary hazards, and operational continuity. These insights help organizations prepare for seismic events and safeguard business resilience.
