1. Manual Sweeping and Cleaning Operations 1.1 Shift Scheduling Under normal circumstances, road sweeping and cleaning operations are organized under either a single-shift or double-shift system, each with distinct operational models, advantages, and disadvantages. 1.1.1 Single-Shift System The single-shift system assigns one sanitation worker per position to perform both comprehensive sweeping and routine cleaning duties. Per contractual requirements, comprehensive sweeping must be completed by 7:00 a.m. daily. Working hours are divided as follows: comprehensive sweeping from 05:00–07:00; routine cleaning from 08:00–11:00 and 13:30–16:30. Advantages and Disadvantages: Advantages include suitability for residential communities, villages, and Class III/IV roads, as well as lower labor costs. Disadvantages include unattended 'vacuum periods' without coverage. Mitigation measures: Adjust working hours appropriately according to seasonal variations and project-specific conditions; deploy mobile cleaning staff during vacuum periods to effectively bridge coverage gaps. 1.1.2 Double-Shift System The double-shift system assigns two sanitation workers per position, rotating shifts to ensure continuous operation for over 16 hours daily. It comprises two subtypes: the 8-hour consecutive shift and the 4-hour rotating shift. Working hours are divided as follows: comprehensive sweeping from 05:00–07:00; 8-hour consecutive shift: morning shift 05:00–13:00, afternoon shift 13:00–21:00; 4-hour rotating shift: sweeping shift 05:00–09:00 and 13:00–17:00, cleaning shift 09:00–13:00 and 17:00–21:00. Advantages and Disadvantages: The 4-hour rotating shift eliminates coverage gaps, ensures stable hygiene quality, and provides adequate rest for staff—ideal for central urban districts and commercial streets. Conversely, the 8-hour consecutive shift entails high physical demands, increased fatigue risk, and potential labor-related hazards. 1.1.3 Cleaning Models Staffing and cleaning models are configured based on project requirements, primarily including: mobile cleaning, one-worker-two-segments, one-worker-three-segments, and two-workers-five-segments. ① Mobile Cleaning: Staff are equipped with rapid-response cleaning vehicles and conduct uninterrupted patrolling within designated zones. This model offers high flexibility and efficiency, suitable for urban areas and major arterial roads. ② One-Worker-Two-Segments: One worker is responsible for cleaning two adjacent segments—ideal for commercial streets and high-pedestrian-density zones. ③ One-Worker-Three-Segments: One worker is responsible for cleaning three adjacent segments. ④ Two-Workers-Five-Segments: Two workers jointly cover five adjacent segments—suitable for industrial parks and low-traffic roads. 1.2 Staffing and Workstation Allocation 1.2.1 Determination of Sweeping and Cleaning Position Staffing Staffing determination process: Measure total area → Calculate mechanization rate → Compute manual sweeping area → Determine average area per worker → Calculate number of positions per shift → Derive total staffing based on shift configuration. ① Measure total project area: Clearly define the operational zone; measure segment widths and compute average values to avoid double-counting. ② Calculate mechanization rate: Mechanically serviceable road area ÷ Total project area = Mechanization rate. ③ Manual sweeping area: Total project area − Mechanically serviced area = Manual sweeping area. ④ Average area per worker: Determine a locally appropriate average area per worker through field sampling across multiple positions. ⑤ Positions per shift: Total manual sweeping area ÷ Average area per worker = Positions per shift. ⑥ Total staffing: Positions per shift × Shift configuration = Project staffing