Request for information: 

"When I asked Twitter "when will Metlink fix their air", I was not expecting much in the way of response from Metlink. I have previously raised the issue of Wellington buses' poor air quality with Metlink, and the response I got back was that no, there were no HEPA filters, and that as Metlink wasn't legally required to do anything about its air quality, it wouldn't be doing anything. 

I could potentially be interested in a meeting with a subject matter expert, but it would be helpful to know in advance what their field of expertise was, and whether that conversation was intended to be two-way? I would be willing to hear about what barriers Metlink is facing in improving its onboard air quality (and whether public health advocates can help with that). Is Metlink also willing to hear about why better indoor air quality on buses is needed? 

If that doesn't sound workable, then an OIA would be an alternative. A more specific question would be: 

When does Metlink plan to either

a) introduce sufficient air exchange to its bus and train air conditioning systems to keep CO2 levels below 800ppm, even at full bus/train capcity, and/or 

b) update its bus and train air conditioning to systems with HEPA filters (with an effective plan for appropriate filter cleaning or replacement), adequate for full bus/train capacity, to reduce the risk of viral transmission between passengers, and between passengers and your drivers;

and if Metlink has no plans to do either of these, why not? 

(N.B. Of the two of these, (a) would be preferable to help your drivers stay alert, but (b) would still be highly valuable for reducing virus transmission. (a) and (b) together would be even better, particularly for your drivers, as they would benefit from the greater alertness of the low CO2, while also being protected from viruses and long-term daily exposure to small particulate matter from road/traffic pollution. Passengers are of course also exposed to road/traffic pollution, but have a shorter total period of daily exposure than do drivers)."