Upplands Motor in Stockholm compares air quality indoor and outdoor



Two AQMesh pods were used to measure NO, NO2, O3 and CO during May and June 2017 at Upplands Motor Stockholm AB car dealership in Sweden, located on the highway between Stockholm city centre and Arlanda airport. The objective was to measure the air quality outside and inside the combined showroom and workshop, demonstrating the importance of measuring common traffic-related pollutants indoors as well as outdoors. The project was also to assess the suitability of AQMesh for this application, including ease of installation and relocation.

The car dealer is situated immediately next to a major highway and the premises are used for car servicing and repairs as well as sales. The air in the building is managed using a standard heating and ventilation management system which ensures adequate air exchange when the building is in operation.

One of the pods was moved indoors between 9th May and 9th June – this can be clearly seen in the temperature plot comparison for both pods during May and June (the pod moved indoors is shown by the blue line on the plot below). The indoor unit showed significantly elevated levels of NO and CO indoors during that time, compared to the unit which remained outside. Although the NO levels indoors largely tracked the outdoor levels, they were consistently around 40-50ppb higher. This may be because the ventilation system is not adequately exchanging air indoors, as the ventilation system in the building is activated at 7am and stops at 6pm when the dealer closes for the day.

The AQMesh pods were then mounted together outdoors again at the end of the indoor trial, clearly showing that the units continued to agree with each other when measuring in the same space, with a pod-to-pod R2 of over 0.8.

Whilst many heating, ventilation and air conditioning systems (HVAC) focus on CO2 measurement – managed through air exchanges – and particle filtration, they can actually make levels of common pollution gases, such as NO2, worse. Air intakes may be situated where outdoor air quality is poor, such as in a car park or near a road, air intake is often during busy traffic periods, and HVAC systems may be switched off just as outdoor air is clearing, trapping pollution indoors overnight.

With diesel exhaust fumes – which include NO2 – now classified as a class 1 carcinogen by the World Health Organisation, forward-thinking companies, such as Upplands Motor, are becoming the first to understand these issues and are focusing on management of indoor air to ensure that the air quality for their workers is at least better than outdoors. AQMesh can also quantify exposure of employees to NO2 and other pollutants when working outdoors, such as on civil engineering sites, directing traffic, or driving a bus.

AQMesh was designed to offer an easy-to-use air quality monitoring system that can deliver localised real-time readings, improving the accuracy and scope of gathering air quality data in order to support initiatives to reduce air pollution and its risk to human health. It continues to be proven as a reliable and accurate instrument for monitoring air quality, whether indoors or outdoors.