Process Safety Progress, Vol.21, No.4, 329-334, 2002
Managing risk of electrostatic hazards in coating and printing on moving webs
When static charges accumulate inflammable or explosive atmospheres, it can lead to an electrostatic discharge (ESD) known to cause fires. This paper will identify hazards attributed to electrostatic charges on moving webs in a flammable-vapor environment, such as in coating and printing processes. Among the reviewed ignition sources are discharges of isolated conductors and insulating webs, as well as human operators as ignition sources. Grounding of conductors and operators, and air ionization for prevention of static buildup on insulators will be examined. This paper also reviews the safety and performance of various static neutralizers, including the importance of computer-generated data to provide information on static conditions and neutralizing equipment status. It will be shown that diagnostic and performance data from static neutralizing equipment can provide valuable input to internal safety evaluations and post-fire investigations. The paper will outline the key elements of a thorough electrostatic bazard risk management program in coating and printing.