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31 None (1) Table 3-6. Maintenance costs from survey compared Severe (5) 0% Mild (2) with Order 5200.9 values. 13% 12% Order Mean Low High 5200.9 Maintenance Cost [$/ft2] $3.05 $0.11 $6.89 $0.36 Ratio of Order 5200.9 8.5 0.3 19.1 1.0 Substantial (4) 25% To assess the durability of the current EMAS technology, Moderate (3) airports were asked to rate the severity of maintenance require- 50% ments for the arrestors on a scale of 1 (none) to 5 (severe). Figure 3-10. Inconvenience of arrestor Airports were questioned about maintenance requirements system installation. in the following six categories: peeling paint, leaching of the material, caulking failure, joint tape debonding, soft tops on arrestor bed, and drainage problems. The severity of main- tenance requirements by category, with respect to the year 3.6. Maintenance that the arrestor was installed, are shown in Figure 3-11 (left). Responses for arrestors that were installed in the same year Airport operators were asked to provide the annual cost were averaged. Average maintenance, which is the average of of maintaining their arrestors. Six airports provided annual the maintenance numbers from each of these six categories, maintenance costs for eight beds. Those maintenance costs is included in Figure 3-11 (right). were divided by the area of the associated arrestor bed to From Figure 3-11, airport operators perceive the current obtain a cost per square foot of arrestor bed. There was a sig- EMAS to require a significant amount of maintenance. In fact, nificant amount of scatter in the maintenance costs reported for all years prior to 2006 (except 2004), the average mainte- by airports, and the average was significantly higher than the nance requirement was above three. That is, in most cases, values suggested by FAA Order 5200.9. The results are shown airport operators perceive the arrestors to require mainte- in Table 3-6. Mean, high, and low costs are included in the nance closer to severe than to none. table and compared to the value in Order 5200.9. For com- Whether the airport had a maintenance contract with parison, the survey values were divided by the Order 5200.9 the manufacturer had little effect on the average mainte- value to provide a ratio to its value. nance required. That is, the weighted average maintenance Peeling paint Leaching Caulk failure Tape debonding Soft tops Drainage problems Maintenance Requirements Maintenance Requirements Year Year Figure 3-11. Maintenance by category (left) and average maintenance (right).