The City of Lowell reserves the right to rearrange or adjust routes and schedules when it is in the best interest of the Public Schools to do so. Route schedules shall be maintained in such a manner that students and parents may anticipate that pickup or drop off will occur within five minutes of the scheduled time. The contractor will provide sufficient vans on a daily basis to meet all regular bus route needs and assignments. Vans will operate at all times that schools are open. All vehicles shall be cleaned by sweeping or vacuum cleaning daily, and shall be maintained free of noxious odors and poisonous gases at all times. In addition, those vehicles, within which a possible exposure to blood borne pathogens has occurred, shall be disinfected in accordance with guidelines set out in 29 CFR Part 1910.1030 or as it may be amended from time to time. The interior and exterior surfaces of all windows shall be maintained in a clean and safe condition, weather conditions permitting. Under no conditions shall vehicles be operated when the operator's vision is impaired by conditions of the glass surfaces to the point where the safety of the passengers is placed in jeopardy. Windows may be opened in the vehicle when weather conditions permit. Operators shall report complaints by students or parents of students to the Superintendent of Schools or his/her designee promptly through the bus company's designee. The operator shall place the safety of student passengers above any other consideration at all times and shall not leave vehicles unattended when students are in the vehicle except for an emergency involving a radio failure and then only if the students are safer in the vehicle than in the surrounding environment...