* * * * * Trees provide a wide variety of benefits to society Trees are living organisms that naturally lose branches or fall The risk to human safety is extremely low Tree owners have a legal duty of care Tree owners should take a balanced and proportionate approach to tree safety management Because trees are unique living organisms, not all practices can be applied in the same way to all trees. Procedures and methodologies should be selected and applied as appropriate, with consideration for what is reasonable and proportionate to the specific conditions and situations. Departures from this BMP should be made with careful consideration of the objectives and with supporting rationale. For litigation defense, the entire assessment and departures from this BMP should be documented. The information in this guide is not sufficient for the arborist to perform tree risk assessment; training and experience are also necessary. In some jurisdictions, certification, qualifications, or licenses are required to conduct tree risk assessments. Figure P1. Contribution of risk assessment to the risk management process. ©IEC. This material is reproduced from IEC 31010:2009 with permission of the American National Standards Institute (ANSI) on behalf of the International Electrotechnical Commission. All rights reserved. 2