How can cyclists protect themselves against air pollution?

A female cyclist attempts to protect herself from air pollution. Image: Getty.

The popularity of cycling in London continues to rise: according to statistics published by Transport for London (TfL), the number of journeys made by bicycle in London grew by 5 per cent in 2018. The transport agency has attributed the upwards trend in cycling to its investment in cycling infrastructure, not least the seven Cycle Superhighways and 12 Cycle Quietways the city now boasts.

Cycling is widely reported to result in health benefits for participants, and cyclists can expect to achieve improvements in both their physical and mental health as a result of switching from public transport or car to a bike. But with air pollution levels remaining stubbornly high across London, should cyclists be concerned that the health benefits they achieve as a result of cycling are actually being outweighed by the dangers posed by increased exposure to air pollution? 

Unlike during the Great Smog of 1952, air pollution today is often invisible to the naked eye. Nonetheless, London breached the European and UK air quality annual limit on 18  March when, for the 36 time this year, levels of pollution particles recorded at a measuring post exceeded the agreed limit. (EU rules allow 35 breaches a year.) Whilst this is a marked improvement on 2018 when the annual limit was broken on the 5 January, it reminds us of the risk that air pollution continues to pose to Londoners today. 

The rise of respirator masks

Anyone who has cycled or walked along one of London's cycle paths in recent years is likely to have seen someone resembling Darth Vader cycling towards them. Protection masks, which are becoming increasingly popular amongst the cycling community, range from cotton surgical masks to respirators with in-built air filtration systems that cover a significant part of the cyclist’s face. 

But do masks actually work and are they worth the investment? 

Cotton masks categorically do not protect wearers against the inhalation of airborne particles. Whilst they can be somewhat effective in protecting against the spread of illnesses, they will not protect a cyclist from air pollution. 

Respirator cycling masks, which range in price from £25 to over £50, are a more sophisticated option. “N99” respirators are said to remove up to 99 per cent of airborne particles from inhaled air. But the particles that cause air pollution today are extremely small, which makes it particularly challenging for respirators to effectively block them from entering the human body. 

Another complicating factor is the fit of the respirator against the human face. Studies have concluded that under “perfect” conditions respirators do effectively filter pollution out of inhaled air. However, when actually fitted to a human face, respirators are often not able to form an effective seal against skin, which ultimately renders them useless. Features such as facial hair and short noses make is particularly challenging for a seal to form. 

The findings of studies into the effectiveness of respirator cycling masks are somewhat mixed – but point to the ineffectiveness of current designs. 

So what can cyclists do to protect themselves? 

The best intervention a cyclist can make to reduce their exposure to air pollution is to avoid the most polluted streets and roads. TfL’s Quietways are an easy way for cyclists to identify the less busy and less polluted roads (although TfL has announced it will be merging the Quietway and Cycle Superhighway networks into a single Cycleways cycle network during summer 2019). 

Cyclists may also consider reducing their cycling speed to reduce their inhalation of airborne particles. The faster and deeper we breathe in polluted air, the more pollutants are delivered to our lungs. Therefore slowing down and reducing their amount of exertion will go some way to protecting cyclists from air pollution. 

Finally, cyclists should check air quality forecasts and make informed decisions regarding their chosen mode of transport on a particular day. TfL provides daily forecasts on its website. 

So should cyclists stop cycling all together? In a word, no. Although there is currently not an effective way to stop yourself from inhaling air pollution whilst cycling, scientists have concluded that the physical and mental health benefits of cycling continue to outweigh the dangers posed by exposure to air pollution. Cycling remains a healthy method of transport for Londoners. 

If you are a cyclist who is concerned about your exposure to air pollution and you are considering investing in a respirator mask, be aware that research suggests they will not protect you effectively. Instead you may want to consider donating the money you would have spent on a respirator to a charity such as Trees for Cities, whose mission is to transform urban areas by creating Urban Forests.


Here’s a fantasy metro network for Birmingham & the West Midlands

Birmingham New Street. Image: Getty.

Another reader writes in with their fantasy transport plans for their city. This week, we’re off to Birmingham…

I’ve read with interest CityMetric’s previous discussion on Birmingham’s poor commuter service frequency and desire for a “Crossrail” (here and here). So I thought I’d get involved, but from a different angle.

There’s a whole range of local issues to throw into the mix before getting the fantasy metro crayons out. Birmingham New Street is shooting up the passenger usage rankings, but sadly its performance isn’t, with nearly half of trains in the evening rush hour between 5pm and 8pm five minutes or more late or even cancelled. This makes connecting through New Street a hit and, mainly, miss affair, which anyone who values their commuting sanity will avoid completely. No wonder us Brummies drive everywhere.

There are seven local station reopening on the cards, which have been given a helping hand by a pro-rail mayor. But while these are super on their own, each one alone struggles to get enough traffic to justify a frequent service (which is key for commuters); or the wider investment needed elsewhere to free up more timetable slots, which is why the forgotten cousin of freight gets pushed even deeper into the night, in turn giving engineering work nowhere to go at all.

Suburban rail is the less exciting cousin of cross country rail. But at present there’s nobody to “mind the gap” between regional cross-country focussed rail strategy , and the bus/tram orientated planning of individual councils. (Incidentally, the next Midland Metro extension, from Wednesbury to Brierley Hill, is expected to cost £450m for just 11km of tram. Ouch.)

So given all that, I decided to go down a less glamorous angle than a Birmingham Crossrail, and design a Birmingham  & Black Country Overground. Like the London Overground, I’ve tried to join up what we’ve already got into a more coherent service and make a distinct “line” out of it.

Click to expand. 

With our industrial heritage there are a selection of old alignments to run down, which would bring a suburban service right into the heart of the communities it needs to serve, rather than creating a whole string of “park & rides” on the periphery. Throw in another 24km of completely new line to close up the gaps and I’ve run a complete ring of railway all the way around Birmingham and the Black Country, joining up with HS2 & the airport for good measure – without too much carnage by the way of development to work around/through/over/under.

Click to expand. 

While going around with a big circle on the outside, I found a smaller circle inside the city where the tracks already exist, and by re-creating a number of old stations I managed to get within 800m of two major hospitals. The route also runs right under the Birmingham Arena (formerly the NIA), fixing the stunning late 1980s planning error of building a 16,000 capacity arena right in the heart of a city centre, over the railway line, but without a station. (It does have two big car parks instead: lovely at 10pm when a concert kicks out, gridlocks really nicely.)

From that redraw the local network map and ended up with...

Click to expand. 

Compare this with the current broadly hub-and-spoke network, and suddenly you’ve opened up a lot more local journey possibilities which you’d have otherwise have had to go through New Street to make. (Or, in reality, drive.) Yours for a mere snip at £3bn.

If you want to read more, there are detailed plans and discussion here (signup required).