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On the air that you breathe when inside aircraft

I am sharing a different kind of article this time. It is still on transportation but more health-related in the sense that the article’s topic is about the air passengers breathe when inside a plane. This is very relevant as we continue to grapple with COVID-19 and other diseases such as influenza, while also trying to get back to our normal activities including traveling whether for family affairs, work, recreation or other reasons.

McGee, W.J. (September 20, 2022) “How clean is the air on planes?” Condé Nast Traveler, [Last accessed: 9/21/2022]

Obviously, there are concerns about the air inside the cabin. But there are other items that one needs to be mindful of if you are truly concerned with the risk of infection.

To quote from the article:

“But some experts have expressed more doubt about the ability to completely scrub the air for zero chance of spreading flu and COVID. “Transmission of infection may occur between passengers who are seated in the same area of an aircraft, usually as a result of the infected individual coughing or sneezing or by touch,” WHO warns. Cabin crew members agree with this assessment. “It’s naive to think an airline can protect passengers 100 percent because you’re in an enclosed space for however long the flight is,…””

The article also provides the following recommendations to travelers (quoted directly from the article and highlights mine):

  • If you’re concerned about aircraft cleanliness, try booking the earliest flight possible that day, as most airlines do a deep-clean each night. And if your itinerary allows it, consider nonstops rather than connecting flights, to limit your exposure to multiple dirty cabins.
  • Wipe down your airline seat and surrounding area with a sanitizing wipe to kill any lingering flu virus; pack an alcohol-based hand sanitizer and wash your hands often.
  • The CDC recommends that most travelers get a flu vaccine in September or October; it also advises to get up-to-date with your COVID vaccines and boosters before any travel.
  • Practice social distancing throughout your journey—at check-in, security screening, boarding, baggage claim, etc. Select seats apart from other passengers (often in the rear) and ask to be moved if possible.
  • Although there is no longer a mask mandate for air travel in the U.S., the CDC still advises travelers ages 2 years and older to opt to wear a face mask in indoor areas of public transportation—such as airplanes, trains, buses, ferries—and in transportation hubs like airports.

There seems so many of what are being termed as revenge travel these days. Many people were not able to travel particularly for family (visits, homecomings) or recreation (vacations) the past 2 years. They are now traveling again as more countries open up for tourism and more people have been vaccinated or gained immunity from the virus. The recommendations above should be heeded as there’s really nothing to lose if we follow them and particularly continue good practices to avoid infection.


On addressing global warming

Here is another quick share of an article; this time on “warming”. The evidence for global warming is strong and we need to address this pressing issue if future generations are to survive a planet that is heating up fast.

Litman, T. (August 31, 2022) “Cool Planning for a Hotter Future,”, [Last accessed: 9/5/2022]

To quote:

“Many of these strategies provide significant co-benefits. For example, reducing road and parking supply with more efficient traffic and parking management helps reduce infrastructure costs and traffic problems, and by reducing impervious surface area it reduces stormwater management costs. Planting more urban shade trees helps create more attractive neighborhoods and increase wildlife habitat. Improving natural ventilation creates more comfortable and healthier buildings, as summarized below.”

I recall people calling for more trees to be planted along roads and how our city streets can become something like Orchard Road in Singapore. I agree with having more trees and other plants, landscaping, along our roads. I also lament the times (and it continues) when the DPWH chopped so many old trees along national roads for road widening projects that didn’t need to destroy so many that gave those roads shade as well as character. We need more change in mindsets particularly when we design highways and streets towards sustainability and yes- reducing heat.

On the impacts of bicycle use

I’ve probably read a lot of posts on social media advocating for bicycle use. Here is another article that provides us with evidence about the impacts of cycling on travel, emissions and health:

Timmer, J. (August 20, 2022) “Here’s What Happens When Countries Use Bikes to Fight Emissions,” Wired, [Last accessed: 8/24/2022]

To quote from the article:

“Globally, adopting a Danish level of bicycle use would reduce annual emissions of CO2 by 414 million metric tons, approximately equivalent to the UK’s emissions in 2015. Boosting that to a Dutch level would eliminate nearly 700 million metric tons, or most of the emissions from Germany in that year.

The researchers also noted that countries like the Netherlands and Denmark have much lower rates of obesity than their peer countries. Based on the known health risks there, they estimate that, globally, we’re already avoiding 170,000 deaths annually due to cycling. Expanding this globally, they found that Denmark-equivalent bicycle use would prevent 430,000 deaths per year. Dutch levels of cycling would prevent 780,000 deaths.

That said, the vulnerability of cyclists to cars poses its own lethal risks. But these aren’t anywhere close to outweighing the benefits from exercise and lower obesity. (They’d add about 90,000 and 160,000 additional deaths per year for the two levels of use.) And if fewer drivers are using cars, there’s a chance that those numbers would come in even lower.

It’s worth noting that these numbers almost certainly underestimate the benefits of shifting to bikes. Bicycles use far fewer resources to produce, and they last longer than most cars. Maintenance is likely to be far less resource-intensive as well. So simply focusing on the use of the bike omits a lot of things that would show up in a detailed life-cycle analysis.

The researchers are certainly correct that there are a lot of locations where weather makes cycling a less-than-ideal option—and the range of places where heat makes it a positively dangerous option is expanding in our changing climate.

But some of the other issues are less severe than they might appear at first. For example, the advent of bicycles with electric assist means that hilly locales aren’t necessarily the barrier they might have been a decade ago. And while a number of countries have large open spaces where cars will remain a necessity, the trend toward urbanization means that most people in those countries will live in places where cycling can be made an option.

So, the biggest barrier is likely to remain the social will to rethink transportation.”

Indeed, social will (as well as political will) is perhaps the biggest barrier in our country. Many people may not agree but the evidence for this is so clear and obvious  that one has to be naive or oblivious to not see it. How else will one explain people sticking to their cars and more readily shifting to motorcycles rather than the bicycle. Of course, there are other factors to be considered and the article actually cites wealth and geography as strong prerequisites in developing a cycling culture. We need to do much more to determine where interventions are needed including land use planning and land development as well as the provision of affordable housing closer to workplaces, schools, shops and other places of interest (Hello 10- or 15-minute cities!).


Take a hike or a walk?

Here’s an interesting article calling for people to go out and spend some time with nature.

The prescriptions mentioned are not at all new, content-wise but the article does mention that people tend to follow prescriptions from their doctors. Perhaps the prescription will be treated or perceived as a more serious matter compared to verbal ones that are interpreted as suggestions and not really all that serious? No matter, the important thing is to be active and keep walking, hiking, jogging or cycling.

The UP Diliman campus’ Academic Oval, along which many people walk or jog in the mornings or afternoons. Biking is currently prohibited along the central loop road of the campus.

Cities and Automobile Dependence: What Have We Learned?

We end the year with an article from Todd Litman via Planetizen. The topic is something that we really need to ponder on as we or if we are to move towards more sustainable transportation for our cities and municipalities. The experiences during this Covid-19 pandemic should have provided us glimpses of how it could be if we put active and public transport above automobile dependence or car-centricity.

Source: Cities and Automobile Dependence: What Have We Learned?

The main article may be found here (in proper citation for academic/researchers reading this):

Newman, P. and Kenworthy, J. (2021) Gasoline Consumption and Cities Revisited: What Have We Learnt?. Current Urban Studies, 9, 532-553. doi: 10.4236/cus.2021.93032.

On the key transformations needed to achieve sustainable, low carbon transport

Also related to COP26, I am sharing material from the Sustainable Low Carbon Transport (SLOCAT) partnership, of which our center is part of. SLOCAT recently released the 11 key transformations for sustainable low carbon land transport urgently needed to meet the climate targets. Here’s a link to their site:

SLOCAT also has the following Wheel of Transport and the Sustainable Development Goals (SDG’s) on the same site. The Wheel illustrates the four cross-cutting themes: equitable, healthy, resilient and green.

SLOCAT Wheel on Transport and the SDG’s –

In the SLOCAT site, they list the following to support the transformations:

Overarching approaches to apply across transport modes and sub-sectors overtime

  • Put people first, not vehicles and technology 
  • Co-create and communicate a compelling vision and targets 
  • Guide short- and medium-term action with clear, coherent political messages 
  • Combine push and pull measures: Regulate and incentivise 
  • Link policies within and beyond transport for synergies 
  • Prioritise resources by social and sustainable value for money 
  • Engage, empower and coordinate stakeholders across government levels and sectors 
  • Build capacity and improve data 
  • Implement pilots to learn and share, then roll out at scale

We need to do more to reduce transport emissions

I did some work on long term action plans on low carbon transport for the ASEAN region before. We were able identify many of interventions that were being implemented as well as those that can be done to reduce transport emissions. Such reductions for the region would ultimately contribute to alleviating global warming. Unfortunately, while ASEAN is a significant contributor to emissions, it pales in comparison to emissions by individual countries like China and the US. If these two and others in the industrialized world do not commit to reducing their emissions, all work will come to naught. Here is an article that serves as a pre-event write-up for COP26, a major climate summit that will be held in Glasgow in the coming days.

On quantifying the benefits of bike share

I’m sharing another article that presents a quantification of Such articles and studies are gaining interest as cycling or biking becomes a popular choice for many seeking an alternative to their usual or former modes of transport. It helps that there are many initiatives promoting active transport in general and cycling/biking in particular.

Wilson, K. (July 23, 2021) “Study: Bike Share Saves the U.S. $36 Million Public Health Dollars Every Year,” StreetsBlog USA, [Last accessed: 8/6/2021]

While the article is about bike share, the conclusions can be extended to cycling/biking in general. The article points to at least 3 major areas where benefits can be derived: safety, air pollution (reduction) and physical activity. To quote:

“I think the message to cities is that bike share — and biking in general, though that’s harder to quantify in the way we do in this study — can contribute a lot to their long term goals,… Most cities want to improve quality of life, the economy, the climate, and their public health outcomes. Bike share does all those things.”

On the importance of trees along streets

I’ve written before about the importance of having parks around a city or town. Here’s an article I recently read about the positive impacts of trees along streets:

Stimpson, A. (March 12, 2021) “Green health: a tree-filled street can positively influence depression, study finds,” The Guardian, [Last accessed: 3/29/2021]

Tree-lined street somewhere in Antipolo City, Rizal

We often refer to cities as the urban jungle. Why not really, literally make cities as urban jungles by planting more trees and other plants where its possible to grow and nurture them. Gardens may be grown not just for flowers or aesthetics but for food. Perhaps architecture should deliberately be oriented for greens? Orchard Road in Singapore is much admired for its trees. Surely, similar streets in our country can be landscaped accordingly.

On using a car for transport in the time of COVID-19

We start the month of February with a very informative articles from the New York Times about car use and the spread of Covid-19. There have been a lot of discussions or discourse, even arguments, about private car use or shared vehicles (e.g., Grab) as people have apparently chosen these over public transport in many parts of the Philippines. For one, there is still a limited supply of public transport as government tries to take advantage of the situation to implement their rationalization and modernization programs.

The following article is from the US but the principles presented particularly about air flow and the potential spread of the virus inside a car are factual and apply in a general manner to other situations including ours. It is important to have an appreciation of the science behind air circulation and how it relates to the potential infections.

Anthes, E. (January 16, 2021) “How to (Literally) Drive the Coronavirus Away,” New York Times, [Last accessed: 2/2/2021]

The common misconception appears to be that using private vehicles automatically helps spread the coronavirus. The science tells us it is not as simple as that (i.e., using your own vehicle will lead to your and your family being infected). While private vehicles are not the proverbial suit of armor vs. Covid-19, their proper use might give better chances compared to crowded and/or poorly ventilated public utility vehicles. Walking and bicycles, of course, are most preferred but that’s a topic for another article.