Boost for air quality monitoring as Nairobi flags off 50 more sensors

Nairobi County’s effort to ensure clean air for the city residents has received a major boost after flagging off 50 more local low-cost air quality monitoring sensors.

The gadget will be installed across the 17 constituencies. This brings the total to 87.

The 87 local sensors will complement two reference-grade monitors that are more accurate but expensive.

The two were installed in September last year at Mama Lucy Hospital and the Fire Station area in the city centre.

The local sensors from the Breathe Cities programme consist of partners - Clear Air Fund, C40 Cities and Bloomberg Philanthropies. Launched on September 11, 2024, it seeks to improve public health by reducing air pollution in participating cities by 30 per cent by 2030. 

“With the official flag-off of 50 city-owned air quality sensors across our capital, Nairobi joins the front ranks of global cities committed to understanding and combating air pollution through cutting-edge technology,” said the County Executive in charge of Green Nairobi, Maureen Njeri.

“This deployment is a cornerstone of our ambitious Breathe Nairobi programme, and it represents much more than the installation of devices. It symbolises empowerment: the power to protect, to plan, and to ensure that every resident, from our children to our elderly, breathes cleaner air.”

Ms Njeri, who spoke along City Hall Way in Nairobi during the flagging off of the 50 sensors yesterday, said air pollution is a silent killer and invisible. She said its consequences are real, including stunting children’s development, threatening the elderly and eroding the health of all Nairobians.

She noted that for too long, lack of reliable data has constrained the city’s ability to act boldly but from today, that era ends.

“These 50 sensors are not simply machines; they are our eyes and ears in the atmosphere. They will give us real-time, hyper-local data at a level of detail we’ve never had before,” she added.

With information from the sensors, she said they will be able to pinpoint pollution hotspots, identify high-risk neighbourhoods, shape life-saving policies based on evidence and empower every resident to make informed decisions about their health.

“We are replacing guesswork with precise knowledge. No longer will we operate in the dark, but we will be guided by verified and actionable data,” said Njeri.

Chief Officer for Environment Geoffrey Mosiria said air pollution is a cross-cutting challenge impacting on the environment, public health and the economy of the city.

“As a rapidly developing city, Nairobi faces significant air pollution challenges that directly impact the health of our citizens, especially our most vulnerable communities,” said Mosiria.

Health budget

Mosiria said a UNEP (United Nations Environment Programme) 2024 report indicated that about 268 deaths annually in Nairobi are linked to air pollution.

“Even more alarming is that 10 per cent of Nairobi’s health budget is currently allocated to treating illnesses related to air pollution. This is to remind us that air quality management is crucial for safeguarding the well-being of us all,” he added.

He said the county has made significant progress in air quality monitoring, thanks to partnerships like the Breathe Nairobi Program with the Clean Air Fund.

Some of the strides he said include the enactment of the Nairobi Air Quality Act 2022, a crucial step in regulating and managing air quality. “We also have the Draft Air Quality Action Plan 2025-2029 and the Draft Air Quality Regulations 2024 that will guide our interventions and enforcement efforts,” he said.

Mosiria said the greening of public spaces has enhanced air quality, reducing urban heat islands and improving the health of Kenyans.

He said the county is working on an air quality data management system and a public portal to make air quality data accessible to the people of Nairobi.

Technical assistance

The chief officer said the county is closing all the illegal dumpsites and has already closed one along Likoni Road. Plans are underway to close another one along Gitanga Road.

Seneca Vieira, technical head for Breathe Cities Africa, said apart from the local sensors usage and data availability, the initiative will also support city officials with technical assistance to develop the Air Quality Action Plan and polices to standardise pollution reduction efforts.

“It will also support communication, advocacy and community engagement campaigns to involve local communities in their work to improve air quality,” said Vieira.

She added that lessons learnt from the Nairobi success will be replicated in other cities on the continent.

Lucile Brethes, head of project delivery at Breathe Cities, lauded Nairobi for standing out as a global leader in clean air action out of the nearly 100 mayors across the globe with whom they work with under C40.

Ms Brethes said with this expanded network of city-owned air quality monitors, Nairobi is not just collecting data but also building the foundation for accountability, transparency and more equitable action.

According to Dr Victor Indasi, Breathe Cities Lead, Kenya, Nairobi is one of the 40 cities globally that joined the initiative that seeks to cut air pollution by 30 per cent by 2030.