Singapore's air quality fell on Friday to the "moderate" from "healthy" level for the first time since November as bush and forest fires spread acros parts of Indonesia. Singapore's environment ministry said its 24-hour pollutant standards index stood at 54 at 8 am, compared with 50 at the same time on Thursday. At the height of the Indonesian forest fires between August and November last year, Singapore's PSI hit a high of 226, prompting nation-wide health notices and official warnings to say inside and limit vigorous outdoor activity.