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Part 1 of 2: Undertaking Seismic Risk Assessments for Buildings Occupied by Government agencies Government Property Management Centre of Expertise in consultation with The Ministry of Business, Innovation and Employment Updated August 2013 1 Contents 1. Objective 2. Scope of guidance 3. Risk management framework 4. Sufficient information to make decisions 5. Choosing a course of action 6. Landlord obligations 7. Advice for building owners regarding earthquake safety of buildings from the Ministry of Business, Innovation and Employment 8. Tolerable risk 2 1. Objective To provide agencies with guidance in utilising information from the Initial Evaluation Process (IEP) and detailed structural assessments and to assist Government agencies (agencies) to make informed decisions and develop appropriate responses to identified risks. 2. Scope of this guidance The Government Property Management Centre of Expertise (PMCoE) has developed this document to encourage consistency in approach and outcomes where agencies have obtained an IEP or detailed structural assessment by a registered structural engineer. PMCoE acknowledges that a “one size fits all” approach is not appropriate for all agencies when developing appropriate responses to buildings with identified seismic risk. This document highlights key considerations that agencies should take into consideration during the decision making process. 3. Risk management framework In considering the response to seismic assessment reports it is useful to recognise that what is being undertaken is the management of risk. Using a recognised risk management framework to work through the issues, risks and options will ensure that a systemic approach is taken when making decisions. A suggested framework is: • • • • • • Define the issues and put them in context; assess the risks (immediate and longer term) associated with the issues identified and the benefits; identify and analyse options for addressing the risks; select an appropriate response to address the risks identified; implement response; and monitor and evaluate results. It is recommended that the framework is undertaken: • In collaboration with stakeholders; and • consideration is given to any new information that may become available that impacts on the initial risks identified. It is important to identify the issues and fully understand the potential consequences. To achieve this, agencies need to ensure that information obtained is correct. 3 4. Sufficient information to make informed decisions Agencies should ensure that they have all the information and understand the potential issues before decisions are made. Much of the recent publicity around structural risk has focused on the percentage of new building standard (% NBS). This however, is only one element within detailed reporting on structural risk. The calculation of the % NBS is not an exact science and is based on each engineer’s judgement. Therefore, there may be significant variations in the % NBS calculation of a building assessment. Furthermore, the % NBS that is provided for in a detailed assessment reflects the lowest NBS part of a building, for example, if an engineer concludes that a building has an NBS of 33% or less, it does not necessarily mean that the entire building is earthquake prone. It could be that only one specific element of it is (i.e. the outer building surface, the “façade”). If a landlord is not intending on obtaining a detailed assessment where the IEP suggests seismic risks could exist, agencies should engage a registered structural engineer to obtain a detailed assessment. Detailed assessments provide more specific structural information. Therefore, if an IEP has identified the possibility of seismic risks, it is advisable to obtain a detailed structural assessment. If it is identified that a specific part of the building could present a risk (for example, stairs, floor seating’s and column ties) refer to the publication from the Ministry of Business, Innovation and Employment called ‘Practice Advisories’. These publications highlight areas of a building that require assessment for earthquake risk and provide guidance. Refer to (http://www.dbh.govt.nz/practice-advisories-index) for the ‘Practice Advisories’. It is important for agencies to analyse the seismic assessment reports to fully understand the structural issues and risks that are the foundation of the % NBS rating. Agencies should review the engineer’s reports and be satisfied that they: • Clearly describe any structural weaknesses within the building. structural weaknesses should be highlighted. Critical • Explain the potential consequences, risks and impacts of the weaknesses identified on the buildings performance in a moderate earthquake. In particular what aspects pose a risk to life safety of building occupants and users. • Provide clear recommendations on options to address the identified structural weaknesses with cost estimates. Agencies should consider other occupants within their buildings, in particular other Government agencies. Assessments and information should be shared and a coordinated response undertaken. Any associated costs should also be shared amongst building occupants. 4 5. Choosing a course of action Each building assessed is unique in character, age, construction, location and use. Agencies need to be cautious about adopting a generic course of action for buildings in their property portfolio. Agencies need to exercise judgement based on the information obtained and evaluate the risks posed from engineers and their assessments. In choosing a course of action in response to seismic assessments agencies should: • Prioritise the safety of staff and the public – the appropriate response will be determined by the identified structural weaknesses and their immediate potential risk to life safety or of injury. The safety of staff and the public must be a primary focus in choosing a course of action. • Address statutory and policy requirements – these would include relevant policies put in place by a local territorial authority and all health and safety requirements as set out in relevant legislation. The Ministry of Business Innovation and Employment has published guidance for building owners (refer to section 7 for a summary of this guidance). • Minimise impact on staff and public – business continuity, maintenance of services and consideration of the personal impact on staff should be factored into response options developed. • Consider potential impact of response on other stakeholders – agencies need to have regard to possible perceptions and precedence that their response might generate and develop appropriate mitigating strategies where risks are identified. • Consider heritage requirements – Cabinet approved a policy in 2004 called the Policy for Government Departments’ Management of Historic Heritage. This Policy provides useful guidance on the management of heritage properties owned by Government departments. The Government developed the policy for Government departments only but agencies in the wider state sector may also find it helpful. The Policy is available on the Ministry for Culture and Heritage website: http://www.mch.govt.nz/research-publications/our-research-reports/policygovernment-departments-management-historic-heritage. Policy 11 may be of particular interest as it directs agencies to the New Zealand Historic Places Trust (NZHPT). NZHPT is the lead national heritage agency and it can provide advice to property owners on heritage management. If you have general questions about the Policy, contact the Ministry for Culture and Heritage directly. • Ensure response is practical and achievable – challenges exist where issues are identified in leased premises (see Section 6). Practical and 5 achievable responses are also linked to the balancing of investment potential cost and risk. • Ensure response investment corresponds with risk – agencies will be faced with a range of options from doing nothing, undertaking a full upgrade or seeking new accommodation. It is important that consideration be given to the risks that have been identified and a judgement made on where the balance between unacceptable and tolerable risk lies (see Section 8). This will help inform decisions about the appropriate level of response and ensure prudent investment. 6. Landlord obligations Most agencies will be occupying buildings that are leased from third party landlords. In relation to seismic assessments and responding to the issues identified, the lessor/ lessee relationship adds a further dimension and can bring with it some challenges. It is important that agencies understand the boundaries within which they are operating before they approach their landlord. Some key points to recognise are: • The contents of the agencies lease will determine what, if any, the landlord’s obligations are to provide information, conduct seismic assessments and undertake remedial work. There is no other legislative authority that directs landlords in this area other than policies in place by local territorial authorities. • The Building Act defines earthquake prone buildings as those having a NBS rating of 33% or less. While some local territorial authorities have goals contained in their policies for building upgrades (67% NBS is common), building owners cannot be compelled to undertake more work than is required to remove the earthquake prone status unless change of use occurs or they are required, such as through specific lease clauses. • Owners of buildings assessed at 34% NBS or greater cannot be compelled to undertake earthquake strengthening work unless a change of use or significant upgrade occurs. • Agencies have obligations as an employer under the Health and Safety in Employment Act 1992 (Health and Safety Act) one such obligation being the provision of a safe working environment for employees or people in the vicinity. The focus of the Health and Safety Act is not the meeting of minimum standards. Rather it sets an expectation that where hazards are identified, all practical steps are taken to remove or minimise the risk posed. It needs to be recognised that compliance with the Building Act 2004 and any policies put in place by a local territorial authorities may not always mean that the requirements of the Health and Safety Act have been met. Employers need to exercise judgement in this respect. 6 7. Advice for building owners regarding earthquake safety of buildings from the Ministry of Business, Innovation and Employment Building owners are responsible for ensuring their building is safe. If a building owner has concerns about their building, they should seek expert advice and act on it. Building owners may be legally required to structurally upgrade their building in the following situations: • When the building’s use is going to be changed, it must comply as nearly as reasonably practicable with the Building Code Structural requirements, as well as means of escape from fire (typically fire exits and alarms), sanitary facilities and disabled access. • If the building is dangerous, insanitary or earthquake prone. An ‘earthquake-prone building’ is a structure that is 33% or less of the new building standard (NBS) for earthquake strength design. Building owners should not wait for the Council to act before dealing with any structural concerns. If you have concerns about your building, you should seek expert advice and fix any identified problems to the extent practicable. The New Zealand Society of Earthquake Engineering recommends that buildings should be strengthened to at least 67% NBS, although owners should not rely solely on the NBS in assessing what action to take. Being ‘earthquake prone’ doesn’t necessarily mean that your building should not be occupied but it does mean that you should get an expert engineering assessment as soon as possible and work out a plan to earthquake strengthen the building. Building owners who are concerned about their buildings should take the following steps: 1. Prioritise building assessments: Make an assessment sooner if the building is used frequently by large numbers of people and is a higher-risk type (For example, unreinforced masonry). 2. Find out everything you need to know to assess risk by obtaining expert engineering advice on: The structural strength of the building. Identify any features, critical structural weaknesses or defects that may be risky Any strengthening work already done Possible short term actions that may decrease risk Other longer term strengthening measures consistent with Council policy and the building owner’s circumstances and plans. • • • • 3. Decide what action to take: 7 • • • Choose the option that provides the best fix, is practical and cost effective, meets Council needs and provides least disruption to tenants, users neighbours and the community In some instances, it may be necessary to close parts or all of the building pending repair Building owners should talk to their tenants about how best to do any strengthening work needed within a reasonable timeframe. 8. Tolerable risk The tolerable risk is defined as a risk society or an individual is willing to live with so as to secure the benefits from taking that risk (for example, the risk of flying versus the benefits of travel) in the belief that the risk is properly being controlled, reviewed and further reduced as and when possible. In everyday life people face a variety of risks and make judgements on whether those risks are broadly acceptable, tolerable or unacceptable. In the context of considering seismic assessment of buildings it is important to have a clear view of what is needed to minimise the risk the structural issues identified raise, recognising it is impossible to eliminate all risk. The ultimate goal of structural work is to provide life safety for occupants and users while acknowledging that in a future seismic event the building could well be damaged beyond repair. To ensure that no unnecessary cost is incurred, agencies need to form a view of where the tolerable risk point is in relation to a particular building and balance this against the requirement to keep staff and the public safe. In addition they should develop strategies and communication approaches to ensure that those impacted are fully informed and understand the rational of such decisions. 8