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Most building owners and occupiers would need to take professional advice to understand the risks and costs of risk mitigation, and to determine the optimal strategy e.g. using the services of structural engineers and insurance brokers. Determining a building’s vulnerability to earthquake damage requires a specialised assessment that takes account of, not only the size of potential earthquakes, but also soil conditions, building height, building materials and construction methods, and design considerations relating to the ‘regularity’ of the building. 1.4 Government responses The market response may be judged inadequate in a number of respects. Information, research and analysis relating to earthquake hazards Information, research and analysis have the essential qualities of public goods. Specifically, they are non-rival goods, which is to say that their use by one member of the community does not diminish the amount of the good that is available to other members of the community. It may be efficient for governments to pay for the production of such goods and arrange for their distribution at the marginal cost of dissemination. The latter is generally close to zero which may mean that such information should be free. GA has the primary responsibility for providing these public goods, which is apparent from the ‘hazard mapping’ activities that are described in section 1.1. Setting standards for earthquake protection In the absence of government intervention, the amount of earthquake protection is decided by building owners and occupiers, but subject to (a) advice from the engineering profession, (b) standards of professional conduct preventing engineers from being involved in the design and construction of unsafe buildings, and (c) the pricing of resultant risks by insurance providers. The potential weaknesses in this decision-making arrangement are as follows: • It is unsafe to assume that building owners and occupiers will generally acquire the information they need to make a sound decision, or even to know that they should consult an expert; • Many decisions would be made by owners and builders while risks of injury or death are unknowingly borne by tenants and their employees; • Professional self-regulation would not be fully transparent and may tend towards the lowest common denominator, particularly during long periods of seismic tranquillity; and • Some decisions are of a public policy kind, that is, where the community would regard the government as accountable, not the engineering profession. For example: o Some buildings need to not only survive an earthquake but also remain functional. Hospitals are obvious examples. Their destruction has the potential to greatly compound the danger to the public in the wake of an earthquake. o The destruction of ‘buildings of assembly’, such as schools and theatres, present a similar threat of enhanced danger to the public, simply on account of the number of occupants. ABCB Regulation Impact Statement (RIS 2007-03) 6
A further consideration is that the building industry would not welcome a piecemeal solution, preferring instead a comprehensive, national approach to building solutions. Importantly, this does not mean that all buildings are provided with the same degree of earthquake resistance, regardless of regional variations in the earthquake hazards and in the significance of the building. The BCA provides for varying degrees of earthquake protection, depending on the severity of regional hazards and the importance of the building. Chapter 3 explains the BCA approach in more detail. We note that COAG’s 2002 report on disaster mitigation and management concludes that … The building and construction industry has a role in promoting natural hazard awareness in the industry and a culture of compliance with building codes and standards (COAG 2002: page 17). The report accepts that there will be both structural and non-structural damage from earthquakes but says that building standards … provide the minimum criteria considered to be prudent for the protection of life by minimizing the likelihood of collapse of the structures (COAG 2002: page 158). Setting of standards for demonstrating compliance Having set minimum standards, the further issue is how to demonstrate compliance with those standards. This is more clearly a matter for the engineering profession to address through its professional associations. However, there can be excessive reliance on volunteers and a role for governments to prompt periodic review, to bear some of the expense of those reviews, and to be appropriately represented at these deliberations, especially where the alternative is that compliance procedures become outdated and lag behind good practice. 1.5 Need for periodic review The earthquake provisions of the BCA 7 are broadly consistent with the philosophy of government intervention that is outlined above. But there is a need for periodic review, recently endorsed by the <strong>Australian</strong> Government. In its response to the recommendations of the Regulation Taskforce (DPMC 2006: page 88), the <strong>Australian</strong> Government agreed that … At least every 5 years, all regulation (not subject to sunset provisions) should, following a screening process, be reviewed, with the scope of the review tailored to the nature of the regulation and its perceived performance. 7 Specifically, the BCA sets design parameters for earthquake resistance and references AS1170.4–1993 (Minimum design loads for structures: earthquake loads) to provide design guidance and a compliance procedure. It sets out data and procedures for determining minimum earthquake loads on structures and components and also minimum detailing requirements for structures in order for buildings to resist the loads or ‘actions’ generated by earthquakes. Chapter 3 of this RIS provides a detailed account. ABCB Regulation Impact Statement (RIS 2007-03) 7
Page 2 and 3: © Copyright 2007 Australian Govern
Page 4 and 5: Recent reports on the management of
Page 6 and 7: TABLE OF CONTENTS EXECUTIVE SUMMARY
Page 8 and 9: These maps summarise the degree of
Page 10 and 11: • The total cost of earthquakes i
Page 14 and 15: Review of AS 1170.4 The earthquake
Page 16 and 17: • Whatever level of protection is
Page 18 and 19: • Specific design for buildings i
Page 20 and 21: Table 3.2 lists the changes, which
Page 22 and 23: • Tiered approach to design proce
Page 24 and 25: Regarding the proposal’s impact o
Page 26 and 27: 4. What proportion of 'work Put asi
Page 28 and 29: Table 4.4 provides information abou
Page 30 and 31: As discussed in section 3.2, this o
Page 32 and 33: Figure 4.2 NZ estimates of the rela
Page 34 and 35: Corresponding BCA load categories S
Page 36 and 37: Public utilities for power generati
Page 38 and 39: 5. STATEMENT OF COMPLIANCE WITH NAT
Page 40 and 41: The RIS was posted on the ABCB webs
Page 42 and 43: To that end, the ABCB has been work
Page 44 and 45: ABCB response: The Consultation RIS
Page 46 and 47: 5. Building occupancy and emergency
Page 48 and 49: • Instead of calculating the prob
Page 50 and 51: 8. IMPLEMENTATION AND REVIEW If ap
Page 52 and 53: REFERENCES Note: all material prep
Page 54: Appendix B: Buildings containing ha

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