With the re-roofing of its terminal imminent, Portland International Airport (PDX) has announced measures to protect travellers from excessive noise.

According to the airport, 15,000ft2 of structure is to be demolished and it is likely that those using the airport between early April and June may hear – or even feel – the work, particularly in the ticketing and security areas. As a result, PDX has introduced five measures to lessen the impact on travellers.

The first involves helping passengers block out of the sound of the demolition work. Dispensers of free earplugs will be positioned in both the north and south ticket lobbies, just before the TSA checkpoints. For travellers with different sensory needs, such as autism or dementia, free sensory kits will be available the Travel Oregon Welcome Center—located pre-security in the baggage claim area. Each kit contains noise-cancelling headphones, a fidget device, an emotional thermometer, and a Hidden Disabilities Sunflower lanyard.

The second measure involves the construction of extra walls. Instead of exposing the interior of the airport to the elements, PDX has built "weather walls" between the terminal and the construction. Those 6in-thick weatherproof walls also provide sound insulation — and in certain spots, the airport has added an extra 2in of drywall to dampen the noise even further.

Thirdly, to minimise disruption in the airport, a team of engineers has developed a detailed demolition plan, and the construction crews will move from the roof down and from the west wall inward. This will help reduce noise, too. "As the structures open up," Hoffman Skanska JV project manager Patrick Bifone explained, "the sound will have a place to escape instead of bouncing around and echoing."

Construction crews will use thick sound blankets to absorb vibration and noise. They may hang the blankets around a zone like a screen or wrap a blanket around a piece they're cutting into. In addition, Hoffman Skanska will set thick Styrofoam pads underneath the concrete being broken up to catch any rubble that falls—and to dampen the sound.

Finally, the airport will continue to monitor the noise level. Jen Reynolds, construction impacts coordinator for PDX, explained, "We will monitor noise levels, and our commitment is that we're always within compliance levels set by NIOSH (National Institute for Occupational Safety & Health)."

Most of the demolition work will take place on weekdays. If a specific task produces intense noise and vibration, Hoffman Skanska may only work on it for a few hours at a time or have night-time crews complete the work when the airport is less crowded.