USRC Safety Rating

The USRC SAFETY dimension reflects the expected performance of the building in terms of loss of life, injury and egress. An average building designed to modern building codes should achieve a safety rating of three to four stars.

USRC Damage Rating

The USRC DAMAGE dimension is an estimate of the cost to repair the building, as a percentage of replacement cost (not including the replacement of contents). Market conditions following the event such as increases in local construction costs may impact repair costs, and the Damage dimension does not include factors such as business interruption losses, historic preservation costs, or mandatory upgrades triggered by building code regulations. An average building designed to modern building codes should achieve a damage rating of two to three stars.

The DAMAGE rating does not include

• Damage caused by fire and water and gas pipe breakage,
• Damage to the building contents or furnishings,
• Market conditions following the event such as increases in construction costs,
• Specialized work to repair historic features or remove hazardous materials,
• Building upgrades or improvements required by building codes, or
• Business interruption economic losses.

USRC Recovery Rating

The USRC RECOVERY dimension is an estimate of the time until a property owner or tenant is able to enter and use the building for its basic intended functions. It represents a minimum timeframe to carry out needed repairs and remove major safety hazards. Included in the Recovery dimension are potential delays in design, financing, and construction that may include long-lead time equipment or materials, a lack of available local design professionals or contractors, and longer than usual permitting and inspection wait times. It does not address several other factors that can delay the time to regain function, including: the condition of external infrastructure (e.g. utilities, transportation); damage to building contents; or the condition of adjacent buildings. An average building designed to modern building codes should achieve a recovery rating of two to three stars.

The RECOVERY rating does not include the time to

• Fully restore all building functions,
• Repair all damage, and
• Repair utilities, transportation systems, adjacent building and other external damage.

Hazard levels

Seismic hazards correspond to an earthquake ground shaking intensity typically required by codes for the design of a new building. This is not the same as designing for a specific magnitude event, because the shaking intensity at a site depends on how far away major earthquake faults are and the soil on which the building sits.

Wind hazards correspond to a 100-year mean recurrence interval for considering functionality and to a 3,000-year mean recurrence interval for considering safety.

The USRC is currently developing ratings for other hazards, including wildfire and flood.

Disclaimers

The USRC Rating is not a precise estimate of building safety, damage and recovery time, given the variables that are not included in the rating and the uncertainty in predicting the exact performance of buildings subject to natural hazards. The USRC strongly recommends that building owners and tenants carefully consider these factors, and then take measures to reduce risks, remove hazards from the work place, and prepare plans for business resumption. The USRC star ratings reflect performance estimates made by USRC certified engineers who have reviewed the building’s engineering design. Many factors beyond the control of an engineer affect the performance of a building

• Hazard intensity often varies from the intensities expected for the region.
• Construction might deviate from the plans, or changes could have been made after the rating has been awarded.
• Building occupants might introduce hazardous materials or create additional hazards.

Disclaimer

USRC Rating Definitions have been derived from technical publications originally developed by the Structural Engineers Association of Northern California (SEAONC). SEAONC granted the USRC permission to use these documents. Any differences between USRC Ratings and related SEAONC documents are solely the work of the USRC and do not reflect any opinion, endorsement, or approval by SEAONC. While US codes and engineering practices are among the most advanced in the world, evaluations of building performance subject to natural disasters include a significant amount of uncertainty: unknowns related to forecasting actual event location, size and duration, the actual intensity to which the building is subject, and the quality of the building design and construction. Current building analysis, evaluation and correlation methods do not address or remove all these sources of uncertainty. Due to many factors including but not limited to variations in construction, differing site conditions, and variations in natural and man-made events, the performance evaluation of a single building includes a significant amount of uncertainty.