The Centre talked to Tyler Radford, Executive Director of the Humanitarian OpenStreetMap Team (HOT), an organization dedicated to humanitarian action and community development through open mapping. We discussed HOT’s signature platform, OpenStreetMap (OSM), adding humanitarian data to satellite imagery, and how to recruit and maintain a massive global network of volunteers.

This interview was conducted by Elizabeth Wood, the Centre’s Communications Manager. It has been edited and condensed for clarity.

When did HOT get its start and how did you get involved? 

HOT formed around the time of the earthquake in Haiti back in 2010. That was one of the first crises where this concept of crisis mapping and disaster mapping was born. With so many people trapped in the rubble, there was a massive international response effort and a need for data on where people were. I volunteered in that initial effort during my graduate program. Five years later, I joined HOT around the time of the earthquake in Nepal in 2015.

How does HOT support humanitarian and development efforts? 

OpenStreetMap is our platform, which you can find at or In a nutshell, we’re trying to map the entire world. While the United States and Europe may have extremely high-quality map data, if you travel to countries where we’re working and open up your favorite map app, you’ll see almost nothing. There are hundreds of thousands of people living in some locations that literally appear as a dot on the map. We feel it’s an injustice. 

At HOT, we focus on mapping the highest risk areas, whether that means natural hazards, displacement or conflict, or disease outbreak. We’re helping people who live in those areas put their locations onto the world map, often for the first time. That’s powerful because it starts to give them a voice in their own disaster recovery and in their own long-term development, just by the simple act of appearing. 

South Sudanese refugees and HOT Uganda field surveyors work together to put Bidibidi Refugee Settlement, Uganda, on the map. (Photo Credit: Humanitarian OpenStreetMap Team)

How do volunteers contribute to OSM both online and on the ground?

Since the earthquake in Haiti, we’ve had 170,000 contributors sign-up to work with us. Anybody who knows how to use a mouse and a web browser can do it; you don’t have to be a GIS expert. We provide satellite imagery from an area that’s been affected by a disaster or crisis using a tool called the Tasking Manager, which is like a grid system. Volunteers are assigned a portion of the grid and they then digitize the satellite imagery. They draw squares or polygons around the buildings or trace the roads or waterways. It’s almost like what you would see in a coloring bookit’s drawing the outlines. 

At the start, the map is almost blank in some areas. As time goes on, local volunteers on the ground will add in street names, the names of health facilities, or even the details of the types of services that a health facility provides. It goes beyond just a map for navigation when all these layers of detail get added. By having local contributors, we believe we can build a more representative map of the world. The more global our team becomes, the better maps we produce, and hopefully the better humanitarian outcomes we can affect. 

Volunteers in Glasgow at a Missing Maps mapathon. (Photo Credit: Humanitarian OpenStreetMap Team)

How do you ensure the data on OSM is accurate?

After each volunteer completes a square, we have a second, more experienced volunteer do what’s called a ‘validation.’ Each square is then combined with tens or hundreds or thousands of squares created by other people in one area, which helps to develop maps that are quite accurate and up-to-date. 

We’re continually working to improve the data that we produce. Sometimes it’s good for one purpose, but might not be good for another. You can think of OpenStreetMap as something like Wikipedia. Fifteen years ago, there was a lot of questionable content on there. Some of the articles weren’t so great and people didn’t really rely on it. If you think about how it is now, it’s a valuable source to go to, at least as a starting point. That’s what OSM has become. 

Can you give examples of specific HOT initiatives?

We have country offices in Uganda, Tanzania, and Indonesia. In these locations, we’re working on a specific crisis. In Uganda, for example, we’re focused on the refugee situation with the Democratic Republic of Congo and South Sudan. We are mapping the refugee settlements in Uganda, which has over a million refugees. In addition to the remote volunteering, we have teams on the groundboth Ugandans and refugees themselvescontributing to the effort. They’re using our tools to map the places where they live. 

Geo-preview image of HOT’s Uganda refugee camps locations dataset on HDX. More HOT data from on the refugee response in Uganda can be found here.

In Indonesia, we’re focused on disaster risk management. After the tsunami in Palu recently [September 2018], we had the national disaster management agency in Indonesia using OSM tools to rapidly gather data in the affected areas. 

We had our colleagues in Tanzania jumping in to respond after Cyclone Idai, and an OSM community in Mozambique also assisted. Disaster response needs to be more localized. Often the first responders are neighbors. 

Do you have any concerns over misuse of the data created for OSM?

Most of the data that we’re producing are things you can typically see on the ground: the buildings, locations, and physical infrastructure. It’s not personally identifiable information. We’re really careful not to map in ways that might identify a certain ethnic group that’s party to a conflict. 

Basically, it’s always a balancing act. Consent is really important to us. People have the power to be added to the map, but they also have the power to delete themselves from the map. We want to make sure the areas we are mapping are chosen consciously, people are aware of what’s happening, and are in agreement that the pros of being visible outweigh the pros of being invisible.

How does HDX support HOT’s vision of creating a free and open map of the world?

There are three parts to our vision: 1) Everyone is counted so that every individual and household has the opportunity to make sure they’re visible on the map; 2) Everyone can contribute so that we’re not only mapping, we’re making sure it’s done through a global network approach; and 3) Map data is accessible and used. This is where HDX comes in. 

HDX has become the go-to location for humanitarian data. Through our partnership, we are able to get much more visibility of the OSM data because it gets published on HDX every 24 hours for many countries. Through this process, we’ve had 38,000 downloads of OSM data from HDX, which is I think a really strong testament to the fact that HDX has helped us to elevate the profile of what we’re doing. 

Our partnership with HDX has also helped to close the loop. Volunteers that are mapping from their home or their school today can see the data they create made available to humanitarian responders within 24 hours for a specific emergency or crisis. It’s always been a part of our mission, but HDX has really helped us to make that connection. 

What’s next for OSM and HDX?

One of our future plans is to better align with the HDX Data Grid. Country pages on HDX get updated with three types of data from OSM. First is the road network, which can be used for things like routing, or GPS navigation on the ground. Second is buildings, which is useful for layering with other types of data. Third are ‘points of interests’, which are basically everything else, such as schools, health facilities, evacuation centers, or shelters. Going forward, we want to say what specifically is in there that could meet a data need. We can align this much better to the Data Grid concept that the Centre is working on.

What do you love about your job?

I love the freedom. As a small organization, we can act quickly, decisively, and with autonomy. I love the people on our team. Everyone who works for HOT are believers in the mission of open data impacting people’s lives. I love the fact that wherever I travel in the world, I get to meet people who are part of our network. It’s like you’re part of this big global family of people who care about using data and information to make our world a better place.