Sufficient body mobility, flexibility, stamina, and balance to perform operational and maintenance tasks which require driving, extensive standing and walking, stooping, pushing, pulling, climbing and working on ladders, and working in enclosed and confined spaces. Sufficient clarity of speech and hearing or other communication capabilities, with or without reasonable accommodation, which permits the employee to discern verbal instructions, communication with other employees and the public, and discern warning or emergency alarms, including vehicle backup warnings.