<p>Including the CAF H-fleet's HVAC system, probably among the loudest in all fleets of both Metrô and CPTM.
</p><p>Estação Carrão - Line 3 - Red
</p>
Sao Paulo, Brazil
<a rel="nofollow" class="external text" href="https://www.flickr.com/people/31018257@N00">Diego Torres Silvestre</a> from Sao Paulo, Brazil
CC BY 2.0
<a rel="nofollow" class="external text" href="https://www.flickr.com/photos/3336/28091674397/">Several types of ventilation</a>