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82 Safety Management Systems for Airports Risk Assumption. accepting the likelihood or probability and the consequences associated with a risk's occurrence. When a risk is classified under an acceptable level, you are assuming that it is low enough that no mitigation action is required in the short term. Risk Control. options and alternative actions that lower or eliminate the risk. Examples include implementing additional policies or procedures, improving the airport infrastructure, developing redundant systems and/or components, and improving training. A control is any- thing that reduces the risk associated with a hazard. Controls can be complex or simple. It is important that they are effective and verified before the change is approved for operation. It is essential that each risk mitigation control is monitored for unintended consequences when put into place. When planning how hazards are to be controlled and risks reduced, the following hierarchy should be considered: Elimination--can the hazard be eliminated completely? (e.g., removing an existing obstacle) Substitution--can the activity or operation be substituted for a lower risk alternative? (e.g., using air bridges or buses to transfer passengers, rather than have passengers walk on the apron) Engineering Controls--is there a technical solution? (e.g., runway incursion prevention sys- tem [RIPS]) Procedural Controls--can procedures be developed? (e.g., SOPs, training, limiting exposure to hazardous operation conditions) Controls closer to the top of the hierarchy are preferable because they are less dependent on human behavior. Elimination of hazards is the first choice in controlling risks, but when this is not practical, isolation and engineering controls should be considered. Administrative controls and PPE may provide interim solutions in a planned program to eliminate or reduce a particu- lar risk, or they may be useful in addition to other control methods. In many circumstances, con- trol solutions will incorporate a combination of controls. 5.7 Example of SRM The example of SRM described in this chapter includes the analysis process for a list of five typical airport hazards. The SRM involves five steps: describe the activity or system, identify haz- ards, determine the risk, assess and analyze the risk, and prioritize and treat the risk. Step 1--Describe the System or Activity Defining and bounding the system or subsystem will help you focus on a specific activity that will assist with having a better assessment of hazards involved with that activity. For example, let's assume the airport will have a new aircraft operating next year. The aircraft is larger than the ones currently operating at the airport. The activity (or system) in this case is "the operation of a new aircraft." In a proactive risk management setting, system (or activity) identification is performed before the hazard identification step. However, in many cases, the identification of a hazard might take place even before the system is identified and lead to an activity (or system) that is the source. As an example, in a daily inspection of the airport airside, the airport on-duty operations officer found some FOD on the runway. The existence of FOD on the runway is a hazard. The system in this case is the whole airside, and the activity causing the hazard may be the construction work

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Safety Risk Management 83 Table 11. Hazard identification in the airport system. How Hazard Hazard Description System Subsystem Activity Was # of Hazard Identified 1 Airside Movement Runway Runway Pilot reports Area operations rubber build- and runway up friction measurements 2 Airside Construction Construction - FOD Pre- Site drainage pipe construction replacement conference near runway threshold 3 Airside Non- Ground traffic in Speeding in Increase in Movement ramp area ramp area speeding Area violations from trend analysis 4 Airside Movement Topographic People Manager's Area survey for crossing meeting runway movement rehabilitation areas 5 Airside Gate Areas Aircraft services People Daily in gate areas approaching inspections at aircraft before the ramp anti-collision light is turned off taking place in the vicinity of the runway. Table 11 contains additional examples of hazards and their associated activities. Step 2--Identify the Hazards for the Activity Once the system, subsystems, or activities are defined, the hazards should be identified. Each activity might incur one or more hazards. For the example of a new large aircraft, some brain- storming questions leading to the identification of hazards may include Is the current ARFF capacity compatible with the new aircraft? Are current taxiway and ramp markings appropriate to the new aircraft? Does the pavement structure of areas used by the new aircraft have sufficient capacity to handle the new loads? Are runway and taxiway width and safety areas compatible with the standards for the new aircraft? Is there enough room at the ramp and gate area to accommodate the new aircraft? Is the AEP compatible with the operation of the new aircraft? Is current training for airport workers compatible with the new operation? Answers to these questions will indicate potential hazards linked to such a change in operation. As a general example for the SRM process, five hazards were assumed in an airside system, as presented in Table 11. The subsystems related to each hazard are also described to facilitate the understanding of the SRM process.

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84 Safety Management Systems for Airports A hazard is not a danger by itself. It is always associated with certain conditions that have the potential to result in an accident: A 15-knot wind can be a hazard if it is blowing across the runway; however, if it is aligned with the runway, it can actually reduce the runway length needed for landing Rubber built up on the runway is only a hazard when it reduces skid resistance if the surface is wet Step 3--Determine the Risk Once you know the hazard, ask yourself what could go wrong. To determine the risk, you should look at all the possibilities, even those that seem to have little chance of occurrence. Table 12 presents the associated risk scenarios for the hazards identified in the previous step. As shown, the presence of FOD may cause damage to aircraft engines if it is sucked in or may cause damage to equipment and people if it is displaced by jet or propeller blast. Step 4--Assess and Analyze the Risk Risk is assessed by evaluating the likelihood (probability) of the occurrence of each risk sce- nario and the severity of the consequences of those scenarios. For each risk scenario, there may be several levels of consequences. If so, you should take the worst credible consequence as the reference for your assessment. As shown in the risk matrix in Figure 11, the likelihood varies from extremely improbable to frequent and the severity varies from no safety effect to catastrophic. The shading of the cells in the matrix represents the risk level (i.e., darkest shading is High Risk, medium shading is Medium Risk, lightest shading is Low Risk). For runway rubber build-up (hazard #1), the worst credible consequence is that the pilot may not be able to control the aircraft during landing. The aircraft will depart the runway at high Table 12. Risk determination for identified hazards. Hazard Description of Hazard Risk Scenarios # 1 Runway rubber build-up (a) Aircraft losing directional control and/or braking capability and departing the runway during operation (overruns and veer-offs) 2 FOD (a) Debris being ingested by aircraft engines (b) Jet or propeller blast displacing debris, equipment, and people 3 Speeding in ramp area (a) Vehicles striking aircraft, other vehicles and equipment, or people 4 People crossing movement (a) Runway incursions areas (b) Jet or propeller blasts displacing equipment or people 5 People approaching aircraft (a) People affected by engine blast, propeller blades, before anti-collision light is or engine suction turned off (b) People being struck by moving aircraft

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Safety Risk Management 85 SEVERITY High Risk RISK No Safety Minor Major Hazardous Catastrophic Effect Medium Risk MATRIX A B C D E Low Risk Frequent 2b 5 L I Probable K 4 E L Remote 5a 3a 2a I 3 H Extremely O Remote 4b 5b 1a 4a O 2 D Extremely Improbable 1 Figure 11. Risks classification using the risk matrix. speed, running beyond the safety areas and eventually striking an existing structure. In this sit- uation, there is a chance of hull loss and multiple fatalities. The severity in this case can be clas- sified in the risk matrix as Catastrophic (E). Then you should evaluate the likelihood. Statistics from past overrun and veer-off accidents indicate a chance of 1 catastrophic overrun or veer-off accident in 15 million operations, given the specific airport and hazard conditions (wet runway). Therefore you can classify this risk as Extremely Remote (2). This hazard, according to the risk of an aircraft departing the runway during a landing oper- ation, is then classified as 2E, which falls in the zone of High Risk (darkest shading). This is labeled as hazard "1a" in Figure 11. The same process can be applied to other hazards and risk scenarios. The results are both marked on the matrix and presented in Table 13. Table 13. Risk level classification. Hazard Description of Likelihood Severity Risk Risk Description # Hazard Level Level Classification (a) Aircraft Runway rubber 1 departing 2 E High build-up runway FOD from (a) FOD ingestion 3 E High 2 construction (b) Jet blast effects 5 C High Speeding in (a) Accidents at the 3 3 D High ramp area ramp Survey workers (a) Runway 2 E High 4 crossing incursions movement areas (b) Jet blast effects 2 C Low People (a) Aircraft engine 3 C Medium approaching effects 5 aircraft before (b) Aircraft striking anti-collision light 2 C Low people is turned off

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86 Safety Management Systems for Airports Step 5--Prioritize and Treat Risk At this point, all the risks associated with identified hazards have been assessed and classified. The next step is to treat the risks; however, for our example, let's say the airport has limited resources and simply cannot eliminate every existing risk. Therefore, we need to find out how to make the best use of limited resources by prioritizing the risks. It is important to note that all risks classified under an unacceptable level should be brought to acceptable levels using mitiga- tion actions. From Table 13, we identified five risk scenarios classified as High, one as Medium, and two as Low. High-risk scenarios are treated first. But among the high-risk scenarios, which should be addressed first? If you compare a 3E risk with a 2E risk, you should treat 3E risk first because, with a similar consequence, the probability is higher for 3E. When comparing 2E and 3D, the latter has a higher probability while the former has higher consequences. In this case, they may be classified in the same priority. Taking this approach, the risk scenarios are prioritized as shown in Table 14. Following the prioritization, it is necessary to decide the actions to treat the risks. Table 15 provides some alternatives for the examples described. It should be noted that some actions will mitigate more than one risk, and some actions may mitigate the risk temporarily, as in hazard #1. Removing rubber build-up is a temporary solu- tion because rubber will continue to build up at the runway surface and removal will be neces- sary from time to time. It is easy to understand the need for continuous risk monitoring, even for treated risks, to ensure their level remains acceptable. A high risk will require immediate attention from the airport operator. Given the urgency of a solution and the limited resources available, the associated action for a high risk may be suffi- cient only to mitigate it to a medium level. For example, for more permanent results, it may take months before the airport is able to develop a safety campaign with focus on vehicle speed at the ramp. A more urgent and possible measure is to intensify enforcement of airport rules while the campaign is being developed. Each hazard identified should be documented and recorded in a hazard log, as described in Table 16. The hazard log should contain a description of each hazard, its consequences, the assessed risk in terms of likelihood and severity, and any required mitigation measures. It should be updated as new hazards are identified and proposals for mitigation are introduced. The log depicted in Table 16 was completed using the examples described in this section. Table 14. Risk scenarios prioritization. Hazard Description of Risk Description Risk Priority # Hazard Classification 1 Runway rubber build-up (a) Aircraft departing runway 2E - High 2 2 FOD from construction (a) FOD ingestion 3E - High 1 (b) Jet blast effects 5C - High 1 3 Speeding in ramp area (a) Accidents at the ramp 3D - High 2 4 Survey workers crossing (a) Runway incursions 2E - High 3 movement areas (b) Jet blast effects 2C - Low 5 5 People approaching (a) Aircraft engine effects 3C - Medium 4 aircraft before anti- (b) Aircraft striking people 2C - Low 5 collision light is turned off

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Safety Risk Management 87 Table 15. Risk treatment actions. Hazard Description Risk Priority Action to Further # of Hazard Mitigate Risk Actions (when required) 1 Runway (a) Aircraft 2 Remove rubber Repave and rubber build- departing build-up groove up runway 2 FOD from (a) FOD 1 Clean up and Provide training construction ingestion define procedure on new to eliminate procedure to source contractor workers (b) Jet blast 1 Clean up and Provide training effects define procedure on new to eliminate procedure to source contractor workers 3 Speeding in (a) Accidents 2 Enforce and Monitor trends in ramp area at the ramp implement safety number of promotion violations and campaign to implement address issue system of accumulated points to suspend and revoke airport driver's permit 4 Survey (a) Runway 3 Provide training to Monitor activities workers incursions contractor and, if necessary, crossing employees have an airport movement escort with the areas survey crew (b) Jet blast 5 Only allow survey None effects job on areas closed to operations 5 People (a) Aircraft 4 Enforce SOP for Monitor violations approaching engine aircraft arrival and establish aircraft effects and departure recurrent training before anti- program for collision light frequent violators is turned off (b) Aircraft 5 Enforce SOP for Monitor violations striking aircraft arrival and establish people and departure recurrent training program for frequent violators

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88 Safety Management Systems for Airports Table 16. Example hazard log table. Consequences Expected Risk Mitigate Risk Responsible Dept/Person Review Date Rating After Risk Rating Closed Out Hazard No. Mitigation Mitigation Action to Potential Location Prior to Hazard Date Date Aircraft Runway Rubber Dept of Jun Jul 3 Runway excursion Apr 1 1 Build-Up (low Engineering 2E- H Remove rubber build-up M 12 2008 08/26 (overrun, 2008 surface friction) (John S.) 2008 veer-off) Clean up and define Jun FOD Aug 1 3E- H procedure to eliminate L 29 Intersection Dept of ingestion 2008 Jan 4 FOD from source 2008 2 of Taxiway A Engineering 2008 construction Clean up and define Jun and C (John S.) Jet blast Aug 3 5C- H procedure to eliminate L 27 effects 2008 source 2008 Dept of Public Enforce and implement Sep 4 Speeding in Accidents at Jul 6 3 Terminal A Safety 3D- H safety promotion campaign M 2008 ramp area the ramp 2008 (Scott L.) to address issue Aug Runway Provide training to contractor Jul 7 May Survey workers Dept of 2E- H M 31 incursions employees 2008 15 4 crossing Terminal C Operation 2008 2008 movement areas (John C.) Jet blast Only allow survey job on 2C- L L effects areas closed to operations Aircraft Enforce Standard Operating Aug People engine 3C- M Procedure for aircraft arrival L 11 approaching Terminal Jun 21 effects and departure 2008 5 aircraft before Terminal A Manager 2008 Aircraft Enforce Standard Operating anti-collision (Lynda F.) light is turned off striking 2C- L Procedure for aircraft arrival L people and departure Note: H, M, and L are high, medium, and low, respectively. The airport's hazards now have been identified and risks determined, assessed, and treated. The SMS records have been organized, placing all information in the hazard log table. However, remember that we need to keep monitoring those hazards and the mitigation measures to ensure they were implemented and that they are effective to mitigate these risks over time.