Contrary to what many people imagine, collective transport can be an important ally in the fight against Covid-19. Proof of this is a recent study by Marcopolo carried out in partnership with Universidade de Caxias do Sul (UCS). The survey shows that air renewal inside the brand’s buses is greater than in environments such as supermarkets and the airport, thus ensuring safety and well-being for customers and collective transport users.
According to the study, all buses produced by the company performed above the standards required by ABNT (Associação Brasileira de Normas Técnicas [Brazilian Association of Technical Standards]) and are also in line with the guidelines and recommendations for air renewal and air conditioning systems of WHO (World Health Organization) and American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE).
Why is air renewal so important?
Air renewal in the environments is an important issue, not only during pandemics. In a place with poor ventilation, viral diseases can proliferate more intensely. A series of viruses and bacteria are transmitted through the air and, as a result, it is essential to ensure its renewal.
In addition to diseases, it is worth mentioning that whenever many people breathe the same air, the release of carbon dioxide into the environment increases and oxygen decreases. This scenario can cause drowsiness and headaches.
Engineer Joel Vicente Ciapparini, Marcopolo’s Engineering coordinator, points out that the efficiency of renewal contributes to better comfort and air quality inside Marcopolo vehicles. “Therefore, all types of possible respiratory diseases are minimized. This air quality is also related to the maintenance and care of the air renewal and air conditioning equipment”, he highlights.
Air renewal of Marcopolo buses is higher than that of supermarkets and airports
The tests carried out in the study by Marcopolo and UCS compare, in terms of air renewal per person, the values of a bus in relation to other spaces. Recommendations for air renewal are described by means of standard ABNT NBR 16401.
Marcopolo models are equipped with air renewal devices covering natural systems, such as air intakes, and also forced systems, such as air conditioning. All of these systems are capable of providing air renewal per passenger, reaching a rate of 23.7 l/s* person.
The data of the study covers all brands/models of Marcopolo´s bodies and the values were obtained considering the conditions of maximum capacity (occupancy), and varying the condition of the static and dynamic vehicle. In this study, it was found that Marcopolo bus bodies provide an air renewal up to 63% higher than the flow required in establishments such as supermarkets (regardless of size), bank branches and airport terminals.
According to Ciapparini, the survey shows that the brand’s systems, when properly used, provide adequate air flow and renewal. “This efficiency is related to the types of air renewal: natural, forced and also air conditioning. Another factor is that the design of the project was planned according to the technical standards in relation to the air flow. All of our planning, starting at the design stage, involves advanced engineering technologies such as simulation and experimental tests”, he highlights.
See the study comparisons
Based on the values obtained during the study, through the execution of tests, it was possible to add the individual flow of each air renewal device and determine the total flow of the body. The values expressed in the table below show an average condition of the factors that impact the calculation, in order to cover the vehicles in a general manner.
Vehicles with air conditioning and at an average speed of 60 km/h were considered, where all available renewal devices are in full use. It is observed that the values for passengers obtained in vehicles, in comparison to the minimum required for renewal of the environments specified by ABNT 16401 show that in almost all cases, the buses presented renewal superior to the other environments, such as supermarkets, airports and shopping centers.
Study demystifies the role of buses in the pandemic
The study carried out by Marcopolo demonstrates that the air renewal capacity of air conditioning devices in buses is an important ally in combating the proliferation of the virus, especially when it occurs in hand with safety measures such as the necessary distance, the use of masks and correctly cleaning the vehicles and air conditioning systems.
The data collected demystifies the idea that public transport is an enemy of the fight against Covid-19. “The study helps make it clear to the user that the Marcopolo bus has efficient air renewal, better than many commercial establishments. The research proves that the higher the rate of air renewal and ventilation, the flow of saliva droplets inside the passenger area is also less, which ends up reducing the exposure and permanence of the virus in the air”, explains Ciapparini.
Sanitization goes beyond air renewal
Air renewal on buses is extremely important to combat the spread of Covid-19, but it is not the only relevant point. Another determining factor is the correct and efficient cleaning of objects and surfaces to disinfect and decontaminate them.
Recently, for example, Marcopolo Next – Marcopolo’s division focused on innovation – presented FIP Onboard, which is the first biosafety product to make collective transport safer from viral contamination. Developed in partnership with Aurratech, it uses products with high bacteriostatic power, and can be applied quickly in the passenger area, driver’s cabin and even in the luggage compartment, with disinfectant action for up to 72 hours.
Important: cautions to take when using ozone
The use of ozone to disinfect the inside of vehicles is a topic that deserves extra attention! Although it is common, the use can be harmful to people’s health if it is carried out in an excessive or improper way. Ozone can only be used as a disinfection tool if it is applied to the closed vehicle, free of passengers.
In Brazil, safe dosages of ozone in work environments follow the determinations of the Brazilian Ministry of Labor and Employment through Regulatory Standard 15, which provides for limits on the tolerance of ozone in activities or operations to which workers are exposed. Factors in the workplace should be considered, such as ventilation and exhaust for the dispersion of residual ozone, as well as real-time monitoring of ozone concentration levels. When applied indoors, there may not be people, animals or plants present.
According to Technical Note No. 26/20206, there are several adverse health effects related to the products that are being used in the modality of disinfecting people. In relation to ozone, mild to moderate exposure can produce symptoms in the upper respiratory tract and eye irritation (for example, lachrymation, burning of the eyes and throat, unproductive cough, headache, substernal pain and bronchial irritation). Attentive to this issue, Marcopolo considers that the correct time and concentration for ozone disinfection are difficult to determine and, therefore, the effectiveness of the method in a large vehicle such as a bus is very questionable. For this reason, the brand invests and indicates strategies and solutions with greater technical evidence and that are not harmful to the health of workers and passengers, as is the case of FIP Onboard mentioned above.
The use of masks and hand sanitizer are essential
It is important to highlight that the Sars-CoV-2 virus, responsible for COVID-19, is a completely unusual situation, and for this reason new discoveries are constantly being made. To this day, entities specialized in air conditioning are favorable to the use of air conditioning equipment in collective transportation, as long as it is properly sanitized and combined with the constant functioning of all air renewal devices available. Windows should be open and fans turned on whenever the possibility exists, keeping in mind that this high use of air renewal systems may cause a loss in the thermal comfort of passengers.
It is also worth remembering that, as specified by Anvisa, the main transmission mechanism of the virus occurs through respiratory droplets and contaminated surfaces. For this reason, air renewal is seen as a tool to help prevent disease transmission. The recommendations and health protocols specified by world bodies, such as the use of masks and hand sanitizer should always be followed, these being the main ways to avoid contamination of the novel coronavirus. The determining factor for the success of the proposed measures is respect and awareness of everyone.