When working on a design/build project, a firm grasp of its intended purpose is critical in order to get the project's design and estimate on the right track early. Recently, I participated in a discussion with a gas facility's project team to establish design parameters for a control room project. As I took notes, I noticed that the terms "shelter-in-place" and "safe haven" were being used interchangeably to describe the building's attributes by members of the team, as if they were the same. I immediately recognized the need to research the designations to educate the team on the unique characteristics of each. After some research, here's what I found.
Safe Havens
Areas or buildings designated as "safe havens" are strategically placed to address predictable, extreme events such as weather (earthquakes, tornados, storms), security breaches (active shooter), toxic releases or potential explosions. In today's environment, safe havens can typically include forced entry and ballistic resistance, and may be stand-alone or built into an existing structure. Both have design elements that provide refuge for predesignated areas and/or personnel until a planned evacuation can be safely conducted or an all-safe declaration can be made. They can have multiple uses, such as a gym, cafeteria or laboratory. Siting is critical for these types of facilities, as quick accessibility is critical during extreme events that can occur within minutes of warnings. Adequate routing, maps and signage identifying safe havens are also necessary in design.
Shelter-in-Place
Areas or buildings designated as "shelter-in-place" are generally designed and implemented around knowledge of quantifiable and described hazards, such as explosions, toxic fumes release, fires and chemical floods. Unlike safe havens, a shelter-in-place structure is designed to protect occupants from an event that occurs without warning, with strong design elements built-in to withstand the entire range of hazards present, and they are sometimes intentionally sited within the hazard area. Typical features of shelter- in-place buildings in petro facilities can include blast resistance, flame-impingement coatings, positive internal pressurization, closed air recirculation and supplementary air supply, among others. These protective features are specified to ensure occupants' survival during an unpredicted event so that an understanding and subsequent control of the event can be managed, including plant shutdown and communicating with authorities and staff. Of critical importance in shelter-in-place design is a well-designed HVAC system with gas and fume detection features, automatic transition into safe mode, and reliable fresh air supply to detect and then prevent toxic fumes from entering the structure. Additionally, doors, windows and all other building penetrations are sealed to prevent leakages that would allow toxic fume infiltration. In many instances, supplementary air options can be added for redundancy.
Control Room Recommendations
There are also many similarities among these two classifications. Emergency power is crucial in both structures, since medical or life-saving operations require both lighting and communications to sustain occupants over time. Additionally, lavatories are required, with some level of potable water supply. Both types of structures can also include oxygen masks and escape hoods, if an evacuation is necessary. Suitable ADA (Americans with Disabilities Act)-compliant sizing based on the number of personnel expected during an event is required in both. FEMA provides guidelines on these standards to guide the initial design layout. Similarly, both types of structures can be designed to accommodate an event that might last a few minutes, or one in which occupants might remain in place for days.
FEMA and OSHA provide design guidelines and recommendations for both types of structures. Though this brief article sheds light on the most obvious and common similarities and differences, it only highlights the topic. If you require a safe haven or shelter-in-place structure at your facility, locate a suitable designer and provider with knowledge and experience to ensure that all your hazards and options are correctly addressed.
For more information, email Bryan Bulling at bbulling@redguard.com or visit www.RedGuard.com.