Tucson businesses are preparing for a national economic blackout on May Day, or International Workers’ Day, as part of a national effort to protest “workers over billionaires’s." The day is also being used as a day of rallies and marches for workers’ rights and social justice. Local First Arizona’�s Director of Tucson Business Development, Chris Mazzarella, expressed concern about potential impact on small businesses across southern Arizona. He suggested that if people do shop Friday, it should be done at small, local businesses.