Reader Comment – 12-10-09 – Water Sprays

Yesterday, our good friend Anonymous left a response to my blog on the use of water sprays as a mitigation measure for toxic release incidents. Anonymous wrote: “Water sprays and other consequence-reduction mitigation measures are sensible for many cases, but they wouldn't be a silver bullet for toxic release attacks: Attackers might sabotage a facility's spray system before releasing toxic chemicals stored there.” Anonymous is absolutely correct. There is no fail-safe system for preventing adverse consequences of a chemical release, just as there is no fail-safe security measure. Nothing is certain in life except death. Having said that, mitigation measures are less vulnerable to intentional disruption then are primary security defenses. The reason for this is that they are harder for an outsider to detect during off-site, or even surreptitious on-site surveillance. The most likely way for them to be identified would be through insider assistance. Since mitigation measures are primarily safety systems rather than security measures, they should be designed to be hard to turn off or disrupt. Only a very limited number of personnel should have access to their controls. Any modification to safety systems should result in multiple alarms going off to warn personnel that a safety critical system has been disabled. Such alarms typically require immediate shutdown of unprotected systems or the application of manual response measures. The same actions would reduce the risks associated with a terrorist attack. But, Anonymous still has a valid point; a mitigation measure should never be considered as a substitute for proper security. It should be part of the multi-layered security system, just as it is only a part of the facility safety system. Facilities should never rely on a single a single security system or a single safety system.