Non-Structural Vulnerability Mitigation in Hospital and Experience in Recent Medium Intensity Earthquake

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1 Non-Structural Vulnerability Mitigation in Hospital and Experience in Recent Medium Intensity Earthquake Dev Kumar MAHARJAN 1, Hima SHRESTHA 2 and Ramesh GURAGAIN 3 1 Earthquake Engineer, National Society for Earthquake Technology-Nepal, Nepal dmaharjan@nset.org.np 2 Director, Earthquake Engineering Research and Training, National Society for Earthquake Technology-Nepal, Nepal 3 Deputy Executive Director, National Society for Earthquake Technology-Nepal, Nepal ABSTRACT Hospitals is one of the most critical facility that needs to be functional during and after the large earthquake. Non-structural elements like equipment and contains covers 80% of construction cost in Hospitals. Generally, non-structural damage occurs even in medium intensity earthquake. The damage in non-structural element not only cause huge monitory loss but also affects in the functionality of the hospital. The hospital cannot provide its services even after medium intensity earthquake if non-structural element are not functional. Therefore, authors think the non-structural vulnerability reduction is necessary to make hospitals functional aftermath of earthquake and is not costly. Each non-structural element first has to be identified as a potential threat in terms of loss of life, property and /or function and the appropriate measures must be identified to reduce or eliminate the risk. The risk reduction option might be different for each individual components. Authors present here the appropriate technology in local context for non-structural vulnerability reduction through this paper. The following reduction measures are identified: removal, relocation, and anchorage, hooking/chaining, strapping, provision of flexible connections in rigid joints, support and modification (plastic lamination in glass panel). Locally available gadgets can be used for different types of reduction measures. Most items can be fabricated in local market using locally available expertise. Authors also present some of the major lessons learn during the implementation of the non-structural mitigation options in different hospitals in Nepal and documented the experience in recent earthquake of M7.8 Gorkha Earthquake on 25 th April 2015 at 11:56AM local time. Most part of the Kathmandu Valley was shaken at medium intensity due to this earthquake. Keywords: non-structural element, non-structural vulnerability, risk reduction measures, appropriate technology, medium intensity 1. INTRODUCTION Hospitals is one of the most critical facilities that needs to be essentially functional immediately after a large earthquake. Non-structural elements like equipment and contains covers 80% of construction cost in Hospitals. Generally, non-structural damage

2 October 2015, Kathmandu, Nepal occurs even in medium intensity earthquake. The damage in non-structural element not only cause huge monitory loss but also affects in the functionality of the hospital. The hospital cannot provide its services even after medium intensity earthquake if nonstructural element are not functional. Therefore, non-structural vulnerability reduction is necessary to make hospital functional aftermath of an earthquake. During the implementation of the project "Enhancing Emergency Health and Rehabilitation Response Readiness Capacity of the Health System in the Event of a High Intensity Earthquake in Kathmandu Valley", detailed non-structural and qualitative structural seismic vulnerability assessment of three hospitals namely, Tribhuvan University Teaching Hospital (TUTH), Shree Birendra Hospital (SBH) and Civil Service Hospital (CHS) and two rehabilitation centers: Army Rehabilitation Center (ARC) and National Disable Fund (NDF) were done during The study showed that the all studied health facilities will have partially operational performance in Moderate level earthquake of intensity MMI VI and MMI VII.During the severe earthquake shaking of MMI VIII and MMI IX, TUTH, CSH and ARC will be partially operational after some time while other two SBH and NDF will be out of function. Non-structural vulnerability reduction measures were also implemented during the implementation of same project. This paper describes the methodology used for the the assessment as well as for the implementation of identified non-structural vulnerability reduction measures. 2. METHODOLOGY The major steps carried out for non-structural seismic vulnerability assessment of hospitals are described below. 2.1 Identification of Critical Systems and Facilities Identification of critical systems and essential functions of hospitals is done based on the functional requirements of the hospital during and after an earthquake. The following steps are followed to identify the critical systems. Step1: Visit the hospital and explain the scope of the work to the hospital administration Step2: Collect information Step3: Visit essential and critical facilities Step4: Visit lifeline facilities Step4: Correlate among structural system, medical facilities and lifeline systems 2.2 Assessment of Individual Component Evaluation of individual equipment and component of all critical systems, all medical departments and administration are assessed to identify the vulnerability of the components after an earthquake. All equipment and components are rated in terms of risk for two earthquakes, moderate earthquake (MMI VI- VII) and severe earthquake (MMI VIII-IX). Risk reduction options, implementation priority and cost estimation for reduction options have also been identified to all equipment. 2.3 Assessment of System Vulnerability All critical systems and medical facilities of the hospitals are assessed based upon the components risk of respective system. Mitigation options for each system are identified New Technologies for Urban Safety of Mega Cities in Asia

3 and critically evaluated in terms of ease and cost of implementation and their expected efficiency regarding vulnerability reduction. The feasibility of implementation mitigation options is defined as either easy to implement or difficult to implement. Similarly, the cost involvement for implementing the mitigation options is identified as low or high cost involvement 2.4 Performance Assessment of Hospital The performance of the hospital in terms of non-structural vulnerability is evaluated at four distinct levels of damage to different critical systems and facilities that the hospital might sustain. The performance level used are defined in Table I. The structural safety of the hospital is also considered while assessing the performance level. Table 1: Non-structural Performance Levels and Damage Description (Adopted from NEHRP Guideline for Seismic Rehabilitation of Buildings, FEMA 273) Performance Expected Levels of Damage to the Different Systems Level and Overall Damage Critical Systems / Components Contents and Equipment of Medical Architectural Elements Operational (Slight Damage) Immediate Occupancy (Slight to Moderate Damage) Lifts operate; ducts and piping sustain negligible damage; the fire response system is functional; transformer / generators are functional and electricity can be provided; water can be provided. All system components are secured; generators start but may not be adequate to service all power requirements; minor leaks in some joints of water supply pipelines; fire systems and emergency lighting systems are functional; medical gas supply systems are secure and Facilities Medical equipment on floors and walls are secure and operable; power is available; equipment on rollers slide but do not tip and do not impact with anything; cupboards, racks cabinets and book shelves do not tip; negligible damage to chemical bottles in the lab; oxygen cylinders and blood stands are not tipped over. Medical equipment on floors and walls are secure but power may not be available; some equipment on rollers slide and impacts with something; cupboards, racks cabinets and book shelves do not tip; negligible damage to chemical bottles in the lab; blood stands may tip. Non-Structural Vulnerability Mitigation in Hospital and Experience in Recent Intensity Earthquake Negligible damage to false ceilings, chimneys, light fixtures and stairs; minor damage to parapets and doors; minor cracks in cladding and partitions. Minor damage to ceilings, chimneys, light fixtures, doors; some window glasses crack; some cracks to partition walls.

4 October 2015, Kathmandu, Nepal Performance Level and Overall Damage Life Safety (Moderate to Heavy Damage) Hazards Reduced Levels (Heavy to Very heavy Damage) Expected Levels of Damage to the Different Systems Contents and Equipment of Medical Facilities Critical Systems / Components functional if electricity is available, lifts are operable and can be started when power is available. Lifts out of service, some breakages to pipelines and ducts; some fixtures broken; electrical distribution equipment shifts and may be out of service; breakages in medical supply systems near heavy equipment. Some critical systems equipment slide or overturn; some piping lines rupture; generators will be out of function; some damage to the fire response system. Medical equipment shift and disconnect from cables but do not overturn; most equipment on rollers slide; some cupboards, racks cabinets and bookshelves tip; some damage to chemical bottles in the lab; lab equipment slide from table. Equipment roll, overturn, slide, and cables are disconnected; some equipment require reconnection and realignment; sensitive equipment may not be functional; cupboards, cabinets and racks overturn and spill contents; severe damage to lab chemicals. Architectural Elements Extensive cracked glass, some broken glass; severe cracks in partitions and parapets; doors jammed; some fracturing to cladding. Generally shattered glass and distorted frames; widespread falling hazard; damage to partitions and parapets; severe damage to claddings; extensive damage to light fixtures. Based upon the structural as well as non-structural seismic vulnerability assessment carried out and the vulnerability of the different critical systems and facilities, the functional assessment of the health facilities was done for two scenario earthquakes, Moderate Earthquake (MMI VI- MMI VII) and Severe Earthquake (MMI VIII-MMI IX). Expected seismic performance of assessed health facilities are given in the Table 2. Table 2: Expected Seismic Performance of Assessed Health Facilities S.N Health Moderate Earthquake Severe Earthquake Facilities 1 TUTH Partially Operational Partially Operational after some time 2 CSH Partially Operational Partially Operational after some time 3 SBH Partially Operational Out of Service 4 NDF Partially Operational Out of Service 5 ARC Partially Operational Partially Operational after some time New Technologies for Urban Safety of Mega Cities in Asia

2.5 Identification of Vulnerability Measures Once a non-structural element has been identified as a

identified to reduce or eliminate the risk.

mitigation in TUTH and CSH, following mitigation measures are carried out: removal, relocation, anchorage,

5 2.5 Identification of Vulnerability Measures Once a non-structural element has been identified as a potential threat in terms of loss of lives, property and/ or function, the appropriate measures are identified to reduce or eliminate the risk. As per the recommendation made during the study for implementation of non-structural vulnerability mitigation in TUTH and CSH, following mitigation measures are carried out: removal, relocation, anchorage, hooking/ chining, strapping, provision of flexible connections in rigid joints, support and modification (plastic lamination in glass panel). During the implementation of non-structural vulnerability measures, the appropriate technology available in local markets of Nepal is used. Locally available gadgets are used for different types of mitigation measures. Some items are fabricated in local market using locally available expertise. a) Removal b) Anchorage c) Refrigerator is anchored to the floor using metal straps Non-Structural Vulnerability Mitigation in Hospital and Experience in Recent Intensity Earthquake

6 October 2015, Kathmandu, Nepal d) A Filter unit in Dialysis Ward is restrainted to movement through framing and metal straps e) Oxygen Cylinders are Restrained from Movement by Chaining f) Chemical Bottles in Laboratory are Secured by Strapping g) Rigid connection between pump and pipeline is replaced with flexible connection h) Glass windows being laminated and laminated glass in laboratory reception Figure 1: Photographs showing different identified mitigation measures New Technologies for Urban Safety of Mega Cities in Asia

7 3. LESSONS Non-structural vulnerability mitigation gadgets can be prepared by using locally available material. The unavailability of non-structural mitigation gadgets in the local markets is one of the reasons that implementation of non-structural mitigation measures was not carried out in general in the context of Nepal. But it is learnt that fabrication of such items in local market using locally available materials and expertise knowledge is possible. Availability of alternate system is necessary to improve critical systems. Critical systems like water supply system should not be interrupted in hospital due to any reason. Therefore, it is a very challenging job to improve seismic performance of the water supply system when there are no alternatives in the system. The job requires mutual understanding and planning for the implementation of vulnerability reduction measures in system among all stakeholders, hospital authority, maintenance department and the implementer Uninterrupted hospital services. The primary challenge for implementation of non-structural mitigation measures in the critical facilities like hospitals is to maintain uninterrupted services 24/7 while accomplishing the mandated work. This requires planning efforts by hospital administrators, doctors, nurses, design team and the team who implements the work. In order to implement the work in intensive care unit such as CCU and ICU, there should be available area in the hospital so that the patients can be relocated from the intensive care unit. Need of schedule. It is most important that the implementer needs to identify the less busy time for any department. In the busy time in any department, it becomes a tough job to continue the implementation work and also, it may create disturbance to the patients and to doctors and nurses in their job. Therefore, it is necessary to identify the least busy time of any department and schedule work accordingly. Circulation of message. It is necessary to circulate the message of implementation work under action in hospital so that implementer can continue their work without any interruption. Meetings with central level are not enough because it is hard to work in departments without convincing department heads. But, it is time consuming to have a meeting with each and every department head during the job in hand. Therefore, ward and department heads need to be kept informed during the planning phase of implementation work. Involvement of hospital staff makes implementation easier. Without the involvement of internal hospital staff in the implementation, the work becomes tougher. Therefore, there should be one hospital staff that can coordinate between different sectors of hospital and with the team involved in implementation work. Use of screw is better than welding in anchorage of steel cupboards. One of the identified techniques to anchor the steel cupboard is welding of angle and steel cupboards and bolting to the strong wall or floor. But, in some Non-Structural Vulnerability Mitigation in Hospital and Experience in Recent Intensity Earthquake

October 2015, Kathmandu, Nepal cases, welding can cause fire hazards. Therefore, it is necessary to be cautious during the use of welding equipment.

Relocation is Technically but Difficult Practically Lack of space for relocation. The non-structural vulnerability assessment found most of the corridors of hospital were covered with cupboards.

8 October 2015, Kathmandu, Nepal cases, welding can cause fire hazards. Therefore, it is necessary to be cautious during the use of welding equipment. Also, welding cannot be performed in chemical storage. Therefore, in most cases, use of screw instead of welding becomes a better technique. Relocation is Technically but Difficult Practically Lack of space for relocation. The non-structural vulnerability assessment found most of the corridors of hospital were covered with cupboards. Cupboards that are placed in corridors can cause life safety hazard or blockage of evacuation routes. Therefore, those cupboards are better relocated. But, due to the lack of space in the hospital buildings, those cupboards will be difficult to relocate. In this case, it is recommended to anchor them in its existing positions. Visual Confidence in Implementation. It is more important to build visual confidence in the implementation of mitigation measures even if it is technically adequate to withstand large earthquake shaking (For example, size of bolts and angles used). 4. Gorkha Earthquake and Experience in Non-Structural Damage in Hospitals Nepal was shaken by magnitude Mw 7.8 (ML 7.6, in terms of local magnitude, Department of Mine and Geology (DMG)) Gorkha Earthquake on 25th April 2015 at 11:56 AM local time. The epicenter of this earthquake is Barpak, Gorkha, 80km North West of Kathmandu Valley. This Gorkha Earthquake was followed by more than hundreds of aftershock including Mw 6.6 and Mw 6.7 within 48 hours and Mw7.3 (ML6.7, DMG) on 12th May 2015 which caused additional damage and casualties. The intensity of shaking was MMI VI and MMI VII in most part of Kathmandu Valley. Even after the shaking of Gorkha Earthquake, TUTH was functional and could treat 700 patients and perform more than 300 surgeries in less than 24 hours and also the Civil Service Hospital (CSH) in New Baneshwor, Kathmandu, Nepal was in continuous operation as TUTH and CSH implemented the non-structural risk reduction measures during 2011 and 2012 and those non-structural retrofitted element performed very well during the Gorkha Earthquake allowing these hospitals to operate continuously. The flexible coupling instead of rigid joint in pipeline of water supply system in TUTH found well functioned during the shaking as it deformed from its original position allowing the shaking prevented from breaking as shown in Figure 2. Figure 2: Residual deflection in flexible coupling after the Gorkha Earthquake in TUTU (Photo: EERI) New Technologies for Urban Safety of Mega Cities in Asia

Figure 3 shows the non-structural damages observed Gorkha Earthquake

Paropakar Maternity Hospital (Photo: EERI) c) Cupboard toppled at

the passage at Kantichildren Hospital (Photo: EERI) e) Rack on right

do not have strapping due to which contents were not prevented from

at Yeti Health Institute Figure 3: Performance of non-structural

9 Figure 3 shows the non-structural damages observed Gorkha Earthquake of 25 th April 2015 in hospitals that yet to implement non-structural vulnerability mitigation measures. a) Filter unit broken down b) Window glass panels shattered in Paropakar Maternity Hospital (Photo: EERI) c) Cupboard toppled at Paropakar Maternity Hospital (Photo:EERI) d) Oxygen cylinders lying in the passage at Kantichildren Hospital (Photo: EERI) e) Rack on right has strapping which prevented the falling of contents and rack on left do not have strapping due to which contents were not prevented from falling (Photo:EERI) f) Hazardous chemical bottles fell from the rack at Yeti Health Institute Figure 3: Performance of non-structural elements in Gorkha Earthquake 2015 Non-Structural Vulnerability Mitigation in Hospital and Experience in Recent Intensity Earthquake

10 October 2015, Kathmandu, Nepal REFERENCES Action Aid Nepal, National Society for Earthquake Technology-Nepal (NSET), Hospital Disaster Preparedness and Response Plan for Bheri Zonal Hospital, Kathmandu. American Society of Civil Engineers, ASCE/SEI Seismic Evaluation of Existing Buildings. ATC 25. Seismic Vulnerability and Impact of Disruption of Lifelines in the Conterminous United States. ATC Proceedings of Seminar on Seismic Design, Retrofit, and Performance of Non-Structural Components. Earthquake Hazards Reduction Series 41. Rapid Visual Screening of Buildings for Potential Seismic Hazards: A Handbook. FEMA 310/January Handbook for the Seismic Evaluation of Buildings A Prestandard. Merlin Nepal &National Society for Earthquake Technology-Nepal (NSET), Seismic Vulnerability Assessment of Five Health Facilities in Kathmandu Valley. Merlin Nepal &National Society for Earthquake Technology-Nepal (NSET), Securing Hospitals against Earthquakes: Implementing Non-Structural Mitigation Measures in Tribhuvan University Teaching Hospitals Standards Association of New Zealand, NZS 4104:1994. Seismic Restraint of Building Contents. Standards Association of New Zealand, NZS 4219:1983. Specification for Seismic Resistance of Engineering Systems in Buildings. Supporting Documentation, and Model Code Provisions, Technical Report MCEER , April 12, Seismic Reliability Assessment of Critical Facilities: A Handbook. World Health Organization (WHO) and National Society for Earthquake Technology- Nepal April Guidelines for Seismic Vulnerability Assessment of Hospitals. Kathmandu. World Health Organization and National Society for Earthquake Technology-Nepal (NSET), December Non-Structural Vulnerability Assessment of Hospitals in Nepal, Kathmandu. World Health Organization and Ministry of Health, Department of Health Services, Epidemiology & Disease Control Division, Kathmandu, Nepal, August A Structural Vulnerability Assessment of Hospitals in Kathmandu Valley, Kathmandu. New Technologies for Urban Safety of Mega Cities in Asia

National Society for Earthquake Technology-Nepal. Structural Vulnerability. Non-Structural Vulnerability. Functional Vulnerability.

Guidelines for Seismic Vulnerability Assessment of Hospitals National Society for Earthquake Technology-Nepal 1133 Devkota Sadak, Kha 2-731, Mahadevsthan, Baneshwor, P.O.Box: 13775, Kathmandu, Nepal Tel: