Alan Auyeung pulled on a pair of latex gloves and a N95 face mask. For good measure, he placed a pair of protective goggles over his eyes too. A trip to the supermarket? In these Covid-19 times, it could have been but, in fact, Auyeung was preparing for a task of quite a different nature: saving the testimonies of Holocaust survivors, whose eye witness accounts of Nazi atrocities were at risk of being eaten away by mold.