MIL-STD-46855 Human Engineering Requirements For Military Systems, Equipment, And FacilitiesThis standard establishes and defines the requirements for applying human engineering to the design, development, and acquisition of military systems, equipment, and facilities. These requirements include the work to be accomplished in conducting a human engineering effort integrated with the total system engineering and development effort. These requirements are the basis for including human engineering in proposals; system, equipment, software and associated user interfaces, and facility analysis, design and test; and documentation and reporting.

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MIL-STD-46855A

function to software and associated user interfaces, hardware, or human operator. Designs shall provide adequate decision support to minimize situations where human decisions are made under conditions of uncertainty, time stress, or workload stress. The conduct of a human error analysis may provide useful information when considering the allocation of functions. The possibility of enhancing human or equipment capabilities through personnel selection and training as well as through equipment and procedure design shall be considered. The costs of personnel selection and training shall be considered in trade-off studies and cost-benefit analyses.

5.1.2 Conduct an analysis of tasks and workload. Human engineering principles and criteria shall be applied to analyses of tasks and workload, including cognitive task analysis if required. These analyses shall also be available for developing preliminary manning levels; equipment procedures; and skill, training, and communication requirements; and as integrated logistic support inputs, as applicable. All analyses of tasks shall utilize the task taxonomy expressed in MIL- HDBK-1908, or appropriately tailored to ensure consistency between human engineering, manpower, and training analyses.

5.1.2.1 Conduct an analysis of tasks. An analysis of tasks shall be conducted and shall provide a basis for making design conceptual decisions. For example, before hardware fabrication, task analyses shall be considered in determining whether system performance and maintenance requirements can be met by the combination of anticipated equipment, software and associated user interfaces, and personnel, and in ensuring that human performance requirements do not exceed human capabilities. Time requirements for tasks shall be evaluated for task duration versus time availability, task sequencing, and task simultaneity. Task requirements shall be evaluated, as applicable, for criticality, accuracy, precision, completeness, and the effects of task feedback and error tolerance/error recovery on performance. These analyses shall also consider effects of sustained and continuous operations on human performance. Tasks identified during human engineering analyses that require performance of critical tasks, reflect possible unsafe practices, or show the potential for improvements in operating efficiency shall be further analyzed.

5.1.2.2 Conduct an analysis of critical tasks. Further analysis of critical tasks shall identify the:

a. Information required by operator or maintainer, including cues for task initiation;

b. Information available to the operator or maintainer;

c. Information processing and decision evaluation process;

d. Possible decisions that could be reached;

e. All possible actions that might be taken depending on the decision reached;

f. Body movements required by all actions that might be taken;

g. Workspace envelope required by all actions that might be taken;

h. Workspace available;

i. Location and condition of the work environment;

J. Frequency and tolerances of all actions that might be taken;

k. Time available for completion of the task;