This was published 30+ years ago, but it makes so much sense I thought it was fitting to share far and wide again.
Each employer must address what actions employees are to take when there is an unwanted release of highly hazardous chemicals. Emergency preparedness or the employer’s tertiary (third) lines of defense are those that will be relied on, along with the secondary lines of defense, when the primary lines of defense, which are used to prevent an unwanted release, fail to stop the release.
Employers will need to decide if they want employees to handle and stop small or minor incidental releases, whether they wish to mobilize the available resources at the plant, and have them brought to bear on a more significant release. Or whether employers want their employees to evacuate the danger area, promptly escape to a preplanned safe zone area, and allow the local community emergency response organizations to handle the release. Or whether the employer wants to use some combination of these actions. Employers will need to select how many different emergency preparedness or tertiary lines of defense they plan to have, develop the necessary plans and procedures, appropriately train employees in their emergency duties and responsibilities, and then implement these lines of defense.
At a minimum, employers must have an emergency action plan (EAP) to facilitate the prompt evacuation of employees when a highly hazardous chemical is released. This means that the employer will have a plan that an alarm system will activate to alert employees when to evacuate, and that physically impaired employees will have the necessary support and assistance to get them to the safe zone as well. These requirements are intended to quickly alert and move employees to a safe zone. Delaying alarms or confusing alarms are to be avoided. Using process control centers or similar process buildings in the process area as safe areas is discouraged. Recent catastrophes have shown that a large life loss has occurred in these structures because of where they have been sited and because they are not necessarily designed to withstand overpressures from shockwaves resulting from explosions in the process area.