On a street corner in the heart of Saint-Germain-des-Prés, Allard has been a quintessential Paris bistro ever since it opened, in 1932. A few weeks ago, though, these two tiny sepia-toned dining rooms lost something of their permanent Édouard Boubat aura with the installation of a shiny new overhead décor of beautiful soldered-and-fitted ductwork and high-tech air filters and fans that was created to ensure an air quality on par with that of a hospital operating room.

Or so I’d been assured by the woman who called to invite me as a food writer to an intimate family-and-friends lunch with chef Alain Ducasse. This meal would debut a new marvel of high-tech engineering intended to reassure gourmets that it’s safe to dine indoors again at their favorite Paris restaurants and cafés since the French government allowed them to reopen on June 15. Previously, Paris restaurants could serve only outdoors and with scrupulous social distancing.