Suggested guidelines for deposited ambient dust

Despite deposited dust being one of the main causes of complaint about air pollution, no international or national (U.K.) standards or guidelines currently exist. Various difficulties in defining nuisance levels for deposited dust have militated against the use of guidelines on anything other than an ad hoc, site-specific basis. However, a need clearly exists for guidelines of wider relevance. A novel method of producing guidelines is proposed for monthly dustfall results based on the background levels normally expected. By adopting the concept of “likelihood of complaint”, already used successfully for rating the impact of noise, the various difficulties inherent in defining dust nuisance standards per se are avoided. Monthly data for British Standard deposit gauges from the Warren Spring Laboratory (U.K.) National Survey of Air Pollution (grit and dust) have been re-analysed by the authors for gauges “sited to catch general deposit”. Where local background data are limited or absent, it is suggested that summary statistics from this analysis of national background data could provide an appropriate basis for the proposed guidelines. Although this method is primarily applicable to British Standard and Frisbee-type deposit gauges, it could be adapted for use with other devices used for monitoring deposited dust.