Situation Awareness Rating Technique
The Situation Awareness Rating Technique (SART) is a fast, subjective way to measure how aware an operator is of a changing situation. You rate ten items grouped into three dimensions: how well you understand the situation, the attentional resources you have available, and the demands the task places on those resources. SART then combines them into a single situation awareness score using the formula SA = U - (D - S).
This is a free taste of the full ErgoSphere platform: the desktop app runs SART sessions for whole teams, links each result to your task analyses and risk registers, and rolls them into audit-ready reports.
Score the Three Dimensions
Move each slider on the 1 to 7 scale to reflect your experience during the task. Understanding and Supply raise your situation awareness; Demand lowers it. Your SART score updates live in the results below.
Situation Awareness Score
SA = U - (D - S). Understanding and Supply push the score up; Demand pushes it down. Scores can range from -5 to +13, and most real assessments fall between 0 and 10.
What is the Situation Awareness Rating Technique?
The Situation Awareness Rating Technique (SART) was developed by Taylor (1990) as a subjective measure of situation awareness, the operator's perception and understanding of a dynamic environment. It gives operators a standardised way to self-report how aware they felt during, or immediately after, a task. SART captures the balance between the cognitive resources an operator has available and the demands the task environment places on those resources.
Unlike objective measures such as SAGAT, which freeze the display and probe what the operator actually knows, SART is non-intrusive and does not interrupt the task. It is a short questionnaire administered post-trial, which makes it practical for field studies and simulation work. It is widely used across aviation, air traffic control, defence, maritime, healthcare and process industries.
SART defines situation awareness as understanding minus the gap between attentional demand and supply. When supply exceeds demand, more resources remain available for building and maintaining understanding, so awareness rises.
The three dimensions
SART builds on Endsley's (1995) three-level model of situation awareness (perception, comprehension and projection), but rather than measuring what awareness is, it measures the operator's experience of it through three constructs:
- Understanding (U): how well the operator comprehends the situation. More understanding means better awareness.
- Supply (S): the attentional resources the operator has available to deploy. More supply means better awareness.
- Demand (D): the attentional demands placed on the operator by the task and environment. More demand means worse awareness.
When to use SART
- Evaluate operator awareness in supervisory control tasks such as air traffic control or process control
- Compare interface designs, automation levels or procedures for their effect on awareness
- Assess whether a training programme improves situation awareness
- Study the relationship between workload and awareness in dynamic environments
- Complement objective measures as part of a multi-method assessment
When another method may fit better
- You need an objective measure of what the operator actually knows (consider SAGAT or SPAM)
- Operators cannot meaningfully reflect on their own awareness
- You need real-time awareness data without a post-task delay
The Ten Items and the Score
SART uses ten rating items grouped into the three dimensions. Each item is rated on a 1 to 7 scale, where 1 is the lowest level and 7 the highest level of that attribute. All ten items use the same direction; the formula, not a reversed scale, accounts for the fact that higher demand lowers awareness.
| Dimension | Item | What it asks | 1 to 7 |
|---|---|---|---|
| Understanding (U) | Information Quantity | How much information have you received? | Very little / A great deal |
| Information Quality | How good is the information you have received? | Very poor / Very good | |
| Familiarity | How familiar are you with this type of situation? | Not at all / Completely | |
| Supply (S) | Arousal | How alert and ready for action do you feel? | Very drowsy / Fully alert |
| Spare Mental Capacity | How much mental capacity do you have available? | None at all / Plenty available | |
| Concentration | How well are you able to concentrate? | Very poorly / Very well | |
| Division of Attention | How well are you able to divide your attention? | Very poorly / Very well | |
| Demand (D) | Instability | How changeable is the situation? | Very stable / Highly unstable |
| Variability | How many variables are you having to consider? | Very few / A great many | |
| Complexity | How complex is the situation? | Very simple / Highly complex |
Calculating the score
Each dimension score is the average of its items, then the composite situation awareness score is calculated:
U = (Information Quantity + Information Quality + Familiarity) / 3
S = (Arousal + Spare Capacity + Concentration + Division of Attention) / 4
D = (Instability + Variability + Complexity) / 3
SA = U - (D - S)
Each dimension falls between 1.0 and 7.0, so the composite score is theoretically bounded by -5.0 and +13.0. In practice most scores sit between 0 and 10. A higher score means better situation awareness.
Reading the result
SART has no official thresholds. These practitioner bands are a common guide and match the colour coding used by this calculator:
| SA score | Awareness level | Suggested action |
|---|---|---|
| 4.0 and above | High | Awareness is adequate. Monitor over sustained periods. |
| 2.0 to 3.99 | Moderate | Review demand sources and consider awareness support aids. |
| 0.0 to 1.99 | Low | Reduce complexity, improve information displays, add training. |
| Below 0.0 | Very low | Redesign the task or interface and add automation support. |
Diagnose with the dimensions, not just the total
Two assessments can share a composite score for very different reasons. Always read the three dimension scores to find the root cause and the right fix:
| Pattern | Diagnosis | Intervention |
|---|---|---|
| Low U, adequate S and D | Information deficit | Improve information displays and feedback |
| Adequate U, low S | Operator resource depletion (fatigue, stress) | Workload management, rest breaks, team support |
| Adequate U and S, high D | Task or environment overload | Simplify the environment, reduce task complexity |
| Low U, low S, high D | System-wide awareness failure | Major redesign, increase automation |
Strengths and limitations
SART is quick (ten items in two to three minutes), low cost, non-intrusive, and multidimensional, so it points to the source of an awareness problem rather than just its size. Its limits are those of any subjective, post-task measure: it relies on recall, captures a single retrospective snapshot rather than real-time dynamics, and operators with genuinely low awareness may not recognise it and rate themselves too highly. For these reasons SART is best paired with an objective measure such as SAGAT and with workload measures such as NASA-TLX.
Frequently Asked Questions
What does the Situation Awareness Rating Technique measure?
SART measures an operator's subjective situation awareness: how well they feel they understand a dynamic situation. It rates ten items across three dimensions, Understanding, Supply of attentional resources and Demand on attentional resources, and combines them into a single SA score using SA = U - (D - S).
How is the SART score calculated?
Each of the ten items is rated from 1 to 7. SART averages the three Understanding items (U), the four Supply items (S) and the three Demand items (D), then computes SA = U - (D - S). Understanding and Supply raise the score while Demand lowers it. The composite score can range from -5 to +13.
What is a good SART score?
There are no universal cut-offs, but a common guide reads 4.0 and above as high situation awareness, 2.0 to 3.99 as moderate, 0.0 to 1.99 as low, and below 0.0 as very low. Always compare scores across conditions and read the three dimension scores, not just the composite number.
How is SART different from SAGAT?
SART is a subjective, post-task questionnaire: the operator rates their own awareness after the task, so it does not interrupt the work. SAGAT is an objective measure that freezes the task and probes what the operator actually knows. SART is quick and non-intrusive, while SAGAT measures SA content directly. The two are often used together.
Is this SART calculator free?
Yes. It runs entirely in your browser with no sign-up, computes the SART score live, and exports a result image. It is a free taste of the full ErgoSphere platform, which runs SART sessions for whole teams and links the results to your task and risk registers.
Further Reading
- Taylor, R. M. (1990). Situational awareness rating technique (SART): The development of a tool for aircrew systems design. In Situational Awareness in Aerospace Operations (AGARD-CP-478, pp. 3/1-3/17). NATO AGARD. apps.dtic.mil/sti/citations/ADA231088
- Endsley, M. R. (1995). Toward a theory of situation awareness in dynamic systems. Human Factors, 37(1), 32-64. doi.org/10.1518/001872095779049543
- Endsley, M. R. (2000). Direct measurement of situation awareness: Validity and use of SAGAT. In M. R. Endsley & D. J. Garland (Eds.), Situation Awareness Analysis and Measurement. Lawrence Erlbaum Associates. doi.org/10.1201/9781003069447
- Salmon, P. M., Stanton, N. A., Walker, G. H., & Green, D. (2006). Situation awareness measurement: A review of applicability for C4i environments. Applied Ergonomics, 37(2), 225-238. doi.org/10.1016/j.apergo.2005.02.005
- Stanton, N. A., Chambers, P. R. G., & Piggott, J. (2001). Situational awareness and safety. Safety Science, 39(3), 189-204. doi.org/10.1016/S0925-7535(01)00010-8
More Free Ergonomics Tools
