A Case Study for a High-Rise Healthcare Facility from SFPE 12th International Conference on Performance-Based Codes and Fire Safety Design Methods

By Juha-Pekka Laaksonen, Nino Ahokas , Samuli Heikkilä, Niko Kauranen, Tommi Nieminen, Juho Pussinen (Team Finland), and Luca Fiorentini (Team Italy)

Teams representing Finland and Italy presented two case studies for a hypothetical high-rise healthcare facility at the SFPE 12th International Performance-based Codes and Fire Safety Design Methods in Honolulu, Hawaii. This article summarizes the case studies. 

Building Description

The building was a high-rise healthcare facility that included inpatient and outpatient care, medical offices, and supporting uses. It was also required to have an associated parking garage.

 

Building rendering by Team Italy.

General Description

• A hospital building with a total of 16 floors (L1 to L16) and a basement.
• An 8-story parking garage adjacent to the hospital, connected to the hospital on Levels 1 to 4 but to be designed as a separate building.
• The conceptual design includes the following major uses by floor level:

• Basement Level — Physical Plant, Laundry, Facilities Department
• Level 1 — Admissions, Emergency Room, Pharmacy, Gift Shop, Storage, Sterile Storage
• Level 2 — Cafeteria, Administrative Offices, Conference Center, Auditorium
• Level 3 — Outpatient Clinic
• Level 4 — Imaging, Laboratory, Physical Therapy, Same-day Surgery
• Level 5 — Operating Suites, Recovery, Cardio Unit
• Level 6 — Patient Care (Maternity)
• Levels 7–12 — Patient Care (80 beds per floor)
• Levels 13–16 — Medical Offices 

• Building footprint of 100 m x 40 m.
• Floor-to-floor height of 3 m per parking garage level, 6 m for the basement level and 5 m per levels 1–12 and 4 m per floor level for levels 13–16.

Video by Team Finland.

Access and Egress

• Main entry to the building is on L1, facing the main street.
• All levels (BL–L16) are connected by elevators (central core). 

Specific Client/Architectural Requirements

• The architectural concept includes atrium space from Levels 1–16, with Levels 1 and 2 and 13–16 open to the atrium.
• Levels 3–12 must provide for temporary horizontal evacuation of patients.

Fire Safety Goals

Each team prepared a performance-based design report for its case study. For each analysis, the design team was asked to meet the following fire and life safety goals: 

1. Safeguard occupants from injury due to fire until they reach a safe place.
2. Safeguard firefighters while they perform rescue operations or attack the fire.
3. Avoid structural failure in the event of fire.
4. Avoid building-to-building fire spread.

Performance-Based Design Report

Each team was asked to address a number of issues in the performance-based design report, including:

• Performance criteria to assess the fire safety goals and objectives.
• Fire risk assessment (unless the design approach (c) is risk-informed or risk-based).
• Description of the fire safety design approach used.
• Fire safety measures.
• How safe egress will be provided for building occupants under a variety of reasonably foreseeable fire scenarios.
• How human behavior was considered.
• Fire scenarios evaluated, and how they were selected.
• How proposed fire safety measures address performance criteria.
• How safety for firefighters will be provided.
• How safety for people with disabilities will be provided.
• Fire safety tools and design methods used in the analysis and designs (i.e., fire models, calculation methods, statistics, fire test data, etc.), including why tools were selected.
• Aspects of the analysis that were modeled, and which were based on engineering judgment.
• Fire safety management requirements, including material control, change of occupancy requirements, education and training, etc.
• How uncertainties were addressed.
• References for all engineering tools and methods, input data, fire tests, occupant characteristics, statistics, etc.
• Drawings and specifications as necessary.

Summaries

Full performance-based design reports for each case study can be found online at the link provided at the end of each summary.

Team Finland

By Laaksonen Juha-Pekka, Ahokas Nino, Heikkilä Samuli, Kauranen Niko, Nieminen Tommi, Pussinen Juho, and Reponen Topi

Team Finland’s design was first outsourced to architect group Reino Koivula and to the local hospital district (HUS). Their special request included two glazed atriums. They used PBD tools to make this possible since prescriptive code would not allow proposed solutions. HUS and fire authorities were also interested in assisted evacuation modeling and the importance of patient room doors closing at the early phase of a fire. Results from evacuation simulations were provided to rescue department to optimize their operational tactics and preparedness planning.

HUS provided data from various evacuation drills. This included several types of patient care units and patient characteristics. Input values for Pathfinder-assisted evacuation simulations were selected using this information. The selected fire scenario in the patient care unit was determined by analyzing the fire characteristics of a typical Finnish patient care room. A αt² fire curve with α=0.012 kW/s² was used until sprinkler activation, after which HRR was kept constant for one minute and then decreased linearly to 1/3 during the next minute. This resulted in a maximum HRR of 433 kW. The case study modeled three evacuation scenarios eled for horizontal evacuation of a patient care unit:

Room door is closed before and after staff person enters the fire room.

1. Door is open until patient is rescued.
2. Door is left open after patient is rescued. 

Computer Simulation of Evacuation Scenarios by Team Finland.

Team Finland concluded that closing patient room doors is vital to successful evacuation of a patient care unit. Even with the high number of staff and relatively short evacuation distance to neighboring unit staff, patients could be exposed to untenable conditions when smoke fills the hallways if the doors are left open.

 The atrium fire scenarios placed, a fast-growing but quickly decaying Christmas tree fire and a slower-growing but longer-lasting furniture fire at the bottom of the atrium where the sprinkler does not limit access to the HRR. These fire scenarios were used to study the possibility of one large compartment fire that is open to the top three floors of the atrium. These included smoke extraction, smoke compartmentation and stair setup. 

The client also requested optimization of glazed structures in the atriums. The team studied whether both integrity and insulation are needed, or if only integrity provides sufficient protection and stops fire spread in some areas. Results showed that this is possible in some parts of the building, but also that large areas of glazing must have insulation properties.

These key factors were identified in the performance-based design process and results: 

• The number of stairs could be optimized using PBD.
• Self-closing doors in patient care units are vital for successful evacuation.
• High-rise buildings bring special challenges for fire safety, but a large number of staff will speed up evacuation of patients.
• A rescue department’s response time is not fast enough to have an active role in horizontal evacuation of patients.
• Even if all fire protection systems operate as designed, it does not ensure tenable conditions and survival for patients in the room of ignition.
• Tools that are normally used only for PBD can also be used for other applications, such as a hospital’s continuity design or staff training.

The Finnish Case Study Report. 

Italy Team

By Luca Fiorentini

The Italy Team performed a fire risk assessment using two methodologies:

• FLAME, a new, semi-quantitative parametric code that enables a quick evaluation of the acceptability of fire safety measures.
• A Fire Safety Evaluation System — a measuring system that compares the level of safety provided in a certain structure to that in a structure that is in compliance with NFPA 101.

The method applied for the fire safety design of the building was the Italian Fire Code D.M. 3/8/15, validated by a RSET-ASET study. Based on the fire risk assessment methods, the main fire scenarios have been identified as:

The fire safety design strategy includes these following measures:

• Minimum door and corridor widths for serving patients needing stretchers, gurneys or wheelchairs.
• Elevators to improve the mobility of impaired occupants to provide effective evacuation and reduction of stair congestion.
• Elevators at two opposite sides of the building, used for occupant evacuation and rescue purposes; access to the elevators takes place through a fire compartment that ensures the adjacent spaces are maintained free of smoke.
• Safe areas of refuge on each floor that offer a place without imminent danger for people to stay or in transit.
• Smoke compartmentation to limit the number of occupants exposed to fire and facilitate the horizontal relocation of patients.
• Restriction of floor-to-floor openings to limit smoke spread between floors.
• A detection system distributed throughout the building — smoke detectors in every compartment and thermal detectors in the kitchen.
• A voice message alarm system to ensure a phased horizontal evacuation and the defend-in-place strategy.
• A sprinkler system installed where offices and storage rooms are located to control fire size and to permit a safe intervention of fire brigade. Based on the risk analysis, a sprinkler system is also recommended for patient rooms to facilitate implementation of the phased evacuation strategy.
• A natural smoke and heat control system (nSHCS) on the roof of the atrium, so the smoke can be extracted vertically and a safe evacuation can be performed on the lower floors.
• A defend-in-place strategy for rooms with patients unable to move.
• Implementation of a phased evacuation strategy supported by an emergency management system that uses …
  • horizontal evacuation to a safe area of refuge on the same floor;
  • vertical evacuation to a floor substantially remote from the incident compartment.
• Strict requirements on fire load to reduce fire size and severity.

The study showed that the proposed fire safety design achieves the set-out performance criteria

The Italian case study performance-base design report. 

By Juha-Pekka Laaksonen, Nino Ahokas , Samuli Heikkilä, Niko Kauranen, Tommi Nieminen, Juho Pussinen (Team Finland) and Luca Fiorentini (Team Italy)