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This briefing will cover general and NSSB worker response actions for an evacuation. Operations Centers, first responders (e.g., LANL Haz-Mat), workers with unique Building Emergency Procedure (BEP) guidance (other than NSSB), etc. are outside the scope of this briefing.
Not provided.
BACKGROUND Future human space exploration beyond Low Earth Orbit (LEO) will require innovative solutions in many areas, primarily those that provide direct medical support to crew on long-duration missions and optimize their health and performance. The associated challenges therein will be numerous, including but not necessarily limited to extended one-way or "asynchronous" communication delays, minimal to non-existent resupply, and a prolonged transit time to "definitive care" ranging from 3-days to 9-months. At the same time, long-duration exploration spacecraft and crew will face restrictions on mass, power, volume, and data far more significant than that seen in current LEO settings. Given these limitations, medical risk assessment is of primary importance, especially evaluating the implications of a medical evacuation of an ill or injured crewmember. Such evacuations are complicated, potentially dangerous, and well may be impossible in certain phases of the mission. Regardless, such issues must be weighed against the risks of the injured crew remaining aboard a spacecraft with limited medical resources. OBJECTIVE This qualitative study drew from the experiences of subject matter experts (SMEs) in spaceflight and appropriate analog environments (i.e., military, disaster, and extreme environment fields) to identify unique principles common amongst medical evacuation considerations helpful in informing future risk assessment tools. Appropriate analog environments included austere operational settings where multiple factors (weather, logistics/limited resupply, denied/extreme environments, and patient condition) resulted in a limited ability to provide definitive local medical care. The fundamental principles in question revolved around scenarios where evacuation became a complicating yet necessary consideration and where life-threatening medical concerns had to be weighed against critical mission objective(s). The primary authors collected semi-structured data gathered through in-depth interviews with 16 subject matter experts (SMEs). Interview questions investigated how these SMEs consider and weigh the attendant risks present in medical evacuation scenarios. Among the critical questions posed were those that sought to understand how the SME balanced the challenges and requirements of medical evacuation (or keeping an injured patient "on-site" aka: "prolonged field care") against the evacuation operation's risks on impacting overarching mission success. The team analyzed interview transcripts for common themes and principles using the qualitative methods of thematic analysis based on consensus, co-occurrence, and comparison. As a result, nine primary risk consideration themes and nine contributing factor themes emerged, all of which will ideally inform future medical evacuation decision-making tools and operational decision-making for exploration class missions. Specific aims for this study included: 1. Identification of common principles used to assess risks and benefits of medical evacuations in extreme environments 2. Identification of common points of friction or complication and challenges in extreme environment evacuations
To meet evacuation needs from carless populations who need personalized assistance to evacuate safely, in this article we propose a ridesharing-based evacuation program that recruits volunteer drivers before a disaster strikes, and then matches volunteer drivers with evacuees once demand is realized. Here we optimize resource planning and evacuation operations under uncertain spatiotemporal demand, and construct a two-stage stochastic mixed-integer program to ensure high demand fulfillment rates. We consider three formulations to improve the number of evacuees served, by minimizing an expected penalty cost, imposing a probabilistic constraint, and enforcing a constraint on the conditional value at risk of the total number of unserved evacuees, respectively. We discuss the benefits and disadvantages of the different risk measures used in the three formulations, given certain carless population sizes and the variety of evacuation modes available. We also develop a heuristic approach to provide quick, dynamic and conservative solutions. We demonstrate the performance of our approaches using five different networks of varying sizes based on regions of Charleston County, South Carolina, an area that experienced a mandatory evacuation order during Hurricane Florence, and utilize real demographic data and hourly traffic count data to estimate the demand distribution.
Response strategies implemented in the first few hours to days after a nuclear detonation on the US homeland may save more than 100,000 lives. Effective planning and pre-event capability development can increase the response efficacy and so the number of lives saved. During such an event, the US Department of Defense, Joint Task Force Civil Support (DoD JTF-CS) provides command and control for the DoD forces supporting civil authority response operations. Among other activities, JTF-CS expects to support FEMA as well as State and local agencies in shelter and evacuation response activities. JTF-CS currently uses a manual method to generate evacuation decision making products. This method compares the dose that would be (a) acquired remaining at a given location to that (b) acquired during evacuation along a small number of routes. In these products, evacuation may be warranted when the projected “remain” dose is greater than the “evacuate” dose. This method only provides a limited consideration of the protection buildings provide their occupants. To inform the JTF-CS nuclear detonation response, the DoD Defense Threat Reduction Agency (DTRA) has tasked Lawrence Livermore National Laboratory (LLNL) to design a set of planning and response products to support shelter-evacuation activities. This report documents these products to facilitate DTRA and JTF-CS planning efforts. To provide context, we also provide appendices that summarize US planning guidance response zones, early (<72 h) response strategies, and other key topics.
The electric vehicle (EV) market has significantly expanded because EVs have lower operational costs while leaving less environmental footprint than internal combustion engine vehicles. However, EVs also come with drawbacks, including long charging time and short operational ranges. With these drawbacks and limited charging facilities, efficient long-distance EV evacuation management is challenging and has not been properly addressed. Without an efficient evacuation plan, serious congestion could happen at charging facilities, the evacuation process would be excessively long, and thus human lives may be put at risk. This study is motivated to investigate the optimal mass evacuation planning for EVs considering limited charging facilities. A three-stage method is proposed to efficiently approach this problem. A case study of Florida hurricane evacuation is conducted. Here, the method's effectiveness is verified by comparing it with a benchmark. Management insights and policy indications are drawn through sensitivity analysis of key parameters.
The digital radiator technology is one of three variable heat rejection technologies being investigated for future human-rated NASA missions. The digital radiator concept is based on a mechanically pumped fluid loop with parallel tubes carrying coolant to reject heat from the radiator surface. A series of valves actuate to start and stop fluid flow to di erent combinations of tubes, in order to vary the heat rejection capability of the radiator by a factor of 10 or more. When the flow in a particular leg is stopped, the fluid temperature drops and the fluid can freeze, causing damage or preventing flow from restarting. For this reason, the liquid in a stopped leg must be partially or fully evacuated upon shutdown. One of the challenges facing fluid evacuation from closed tubes arises from the vapor generated during pumping to low pressure, which can cause pump cavitation and incomplete evacuation. Here we present a series of laboratory experiments demonstrating fluid evacuation techniques to overcome these challenges by applying heat and pumping to partial vacuum. Also presented are results from qualitative testing of the freezing characteristics of several different candidate fluids, which demonstrate significant di erences in freezing properties, and give insight to the evacuation process.
An evacuated or vacuum airship relies on the same principle of buoyancy used by standard balloons. However, unlike a balloon which uses a lighter than air gas to displace air and provide lift, the vacuum airship leverages a rigid structure to maintain a vacuum and displace air, thereby providing buoyancy. This method is similar to how a ship uses a rigid structure to displace water and fill the space with air; an evacuated airship uses the same mechanism, except air is displaced and the space remains vacant. Using this method, the evacuated airship is capable of utilizing the full potential of the displaced mass of air, which has interesting implications in the Martian atmosphere. Unlike other aerial vehicles, which are at a disadvantage in Martian atmospheric conditions, the evacuated airship benefits from the Martian atmosphere by virtue of the temperature and molecular composition. As a result, the evacuated airship offers an unprecedented payload capacity and, if implemented, may be used to transport current and future scientific instruments, other vehicles, rovers, and possibly even human habitations. A standard dirigible or balloon for Mars would have a severely limited span of operation and a very narrow field of study, nearly exclusively the atmosphere, but a vacuum airship can be used as a long term tool for many different missions: transportation, ground study, communications, atmospheric study, etcetera, thereby making it a far more economically sensible choice
In rapid-onset disaster scenarios such as wildfires, evacuation traffic often significantly deviates from historical patterns, rendering conventional data-driven forecasting methods less effective. To address this challenge, we propose an improved algebraic derivative estimation (ADE) incorporating particle swarm optimization (PSO) for real-time traffic flow prediction. Our approach dynamically adjusts the ADE prediction time window at each step by minimizing a cost function based on the mean and variance of accumulated forecasting errors within the window, thereby balancing bias and variability. We evaluate the method using traffic data from the January 2025 California wildfires, focusing on key road segments critical for large-scale evacuations. The results demonstrate that our approach surpasses established machine learning and deep learning models—XGBoost, LSTM, and GRU—in predictive accuracy and maintains high computational efficiency. Notably, the proposed method eliminates the need for offline model training. Moreover, rapid PSO-based tuning enables real-time deployment, which provides a crucial advantage in scenarios where evacuation timings and road closures change dynamically. In conclusion, these findings highlight the benefits of the PSO-enhanced ADE framework for emergency traffic management, where rapid, data-sparse forecasts are essential for effective evacuation planning.
On April 1, 1946, an earthquake off Unimak Island, Alaska, generated a tsunami that raced across the Pacific. One of the islands in danger was Kwajalein, the logistical hub for Operation Crossroads. Commodore Ben Wyatt, the U.S. naval commander of the Marshall Islands, ordered the evacuation of “10 Red Cross workers, 19 USO women, 17 native women, 16 male [hospital] patients, four tiny babies, one small boy, and two navy doctors,” to the USS Rockbridge, which then steamed in deep water off the atoll until the danger passed. One of the Red Cross workers, Reva Hurwitz, played bridge in the ship’s wardroom until 2 a.m., a luxury since the island curfew, strictly enforced, was 10:30 pm. The tsunami bypassed Kwajalein, and everyone returned to the island less than twenty-four hours after being evacuated. Although the evacuation proved unnecessary, the women were grateful, said Hurwitz, because they had the opportunity “to use hot water and eat fresh fruit.”
Evacuation areas for accidental spills of toxic propellants along rail and highway shipping routes are defined to help local authorities reduce risks to people from excessive vapor concentrations. These criteria along with other emergency information are shown in propellant spill cards. The evacuation areas are based on current best estimates of propellant evaporation rates from various areas of spill puddles. These rates are used together with a continuous point-source, bi-normal model of plume dispersion. The rate at which the toxic plume disperses is based on a neutral atmospheric condition. This condition, which results in slow plume dispersion, represents the widest range of weather parameters which could occur during the day and nighttime periods. Evacuation areas are defined by the ground level boundaries of the plume within which the concentrations exceed the toxic Threshold Limit Value (TLV) or in some cases the Emergency Exposure Limit (EEL).
A computer simulation was developed to assess passenger survival during the post-crash evacuation of a transport category aircraft when fire is a major threat. The computer code, FIREVAC, computes individual passenger exit paths and times to exit, taking into account delays and congestion caused by the interaction among the passengers and changing cabin conditions. Simple models for the physiological effects of the toxic cabin atmosphere are included with provision for including more sophisticated models as they become available. Both wide-body and standard-body aircraft may be simulated. Passenger characteristics are assigned stochastically from experimentally derived distributions. Results of simulations of evacuation trials and hypothetical evacuations under fire conditions are presented.
The hyperfine resonance observed in evacuated wall-coated cells with dimensions lambda/2 (lambda is the hyperfine resonance wavelength) consists of a narrow Dicke sub-Doppler linewidth feature, the spike, superimposed on a broad pedestal. The hydrogen maser provides a classic example of this lineshape. As cell size is increased, an effect unique to evacuated wall-coated cells occurs. Certain combinations of microwave field distribution and cell size result in a lineshape having a pedestal with a small spike feature or only the broad pedestal with no spike. Such conditions are not appropriate for atomic frequency standard applications. The cause of the evacuated wall-coated cell lineshape is reviewed and methods to recover the narrow spike feature without restrictions on cell size is discussed. One example is a cell with dimensions having equal volumes of exposure to opposite phases of the microwave magnetic field.
Introduction: Achieving NASA's Space Exploration Vision scientific objectives will require human access into cratered and uneven terrain for the purpose of sample acquisition to assess geological, and perhaps even biological features and experiments. Operational risk management is critical to safely conduct the anticipated tasks. This strategy, along with associated contingency plans, will be a driver of EVA system requirements. Therefore, a medical contingency EVA scenario was performed with the Haughton-Mars Project/NASA to develop belay and medical evacuation techniques for exploration and rescue respectively. Methods: A rescue system to allow two rescuer astronauts to evacuate one in incapacitated astronaut was evaluated. The systems main components were a hard-bottomed rescue litter, hand-operated winch, rope, ground picket anchors, and a rover-winch attachment adapter. Evaluation was performed on 15-25deg slopes of dirt with embedded rock. The winch was anchored either by adapter to the rover or by pickets hammered into the ground. The litter was pulled over the surface by rope attached to the winch. Results: The rescue system was utilized effectively to extract the injured astronaut up a slope and to a waiting rover for transport to a simulated habitat for advanced medical care, although several challenges to implementation were identified and overcome. Rotational stabilization of the winch was found to be important to get maximize mechanical advantage from the extraction system. Discussion: Further research and testing needs to be performed to be able to fully consider synergies with the other Exploration surface systems, in conducting contingency operations. Structural attachment points on the surface EVA suits may be critical to assist in incapacitated evacuation. Such attach points could be helpful in microgravity incapacitated crewmember transport as well. Wheeled utility carts or wheels that may be attachable to a litter may also aid in extraction and transport. Utilizing parts of the rover (e.g. seats) to deploy as a litter may be considered. Testing in simulated 1/6-g to determine feasibility of winch operation and anchor establishment will further reduce implementation uncertainties.
Water hammer analysis in pipe lines, in particularly during priming into evacuated lines is important for the design of spacecraft and other in-space application. In the current study, a finite volume network flow analysis code is used for modeling three different geometrical configurations: the first two being straight pipe, one with atmospheric air and other with evacuated line, and the third case is a representation of a complex flow network system. The numerical results show very good agreement qualitatively and quantitatively with measured data available in the literature. The peak pressure and impact time in case of straight pipe priming in evacuated line shows excellent agreement.
Traditionally, mission planners have used a heuristic and qualitative approach to design medical systems based on prior experience however this approach may result in high variability and implicit bias to design and could put missions and crewmembers at risk. The Informing Mission Planning through Analysis of Complex Tradespaces (IMPACT) tool is a probabilistic risk assessment tool designed by NASA to model medical risk in long duration missions outside of low earth orbit (LEO). This tool can quantify risk metrics such as risk of crewmember death, loss of crew task time, and the need for medical evacuation to better inform and augment the more traditional approach to medical system design. The risk metric of Return to Definitive Care (RTDC) represents the likelihood of requiring medical evacuation and has been difficult to quantify in a reliable and standardized manner. Initial development of the RTDC metric was constrained due to the complexity of a medical evacuation decision and the lack of prior spaceflight data and this presentation will discuss the review and improvement process used to increase model accuracy and fidelity.
Exploration beyond low Earth orbit requires innovative solutions to support the crew medically, especially as the opportunity for timely evacuation to Earth diminishes. This includes assessing the risks and benefits that a complicated medical evacuation (MEDEVAC) poses to the injured crewmember and crew and to accomplishing the mission. This qualitative study identifies common MEDEVAC risk assessment principles used in spaceflight and other extreme environments to better inform future risk assessment tools and exploration mission concepts.
Seal-off assembly which permits rapid container evacuation using large diameter tubing has a vacuum valve that permits sealing plate transfer from the vacuum valve stem to the container after evacuation. The sealing plate can be reused repeatedly. This device can repump in case of a small leak without exposing the container to the atmosphere.