Like other natural emergencies, volcanic ashfalls are unplanned events that can affect businesses. Ashfall often leads to a temporary shutdown of business operations (hours to days or longer), and may cause physical damage to buildings, equipment, computers, machinery, vehicles, inventory and supplies. Furthermore, many explosive eruptions over a period of weeks to months can result in repeated ashfalls that require costly cleanup operations after each event. Making a general plan to deal with emergencies and a specific plan for ashfall is one of the most important steps to take to mitigate the potential effects of ash and improve the response and recovery of a business to ashfall. Resources are available elsewhere for developing emergency and contingency plans (for example, a planning guide from FEMA).
During non-eruptive periods, businesses and organizations should consider their vulnerability to volcanic ashfalls. Once the vulnerability has been assessed, mitigation strategies can be developed. Three types of approaches can be used (Johnston and Becker, 2001):