Description
Subtract overflowLevel from rimLevel for freeboard.
A site clearance is a signed difference between available space and an object or allowance. A supplied setback and assumed future envelope are separate from actual legal or environmental requirements.
Subtract overflowLevel from rimLevel for freeboard.
When to use this tool
Use Rain Garden Freeboard Level Pair when you need one explicit landscape clearance margin.
How to use the tool and how it works
- Enter overflowLevel, rimLevel. Use the units and conventions below.
- Run the tool. Correct any format, range, or cross-field input error before interpreting the output.
- Read freeboard. Use the output convention below.
Subtract overflowLevel from rimLevel for freeboard.1
| Input field | Meaning and units | Accepted input |
|---|---|---|
| overflowLevel | Overflow Level | Required. Finite number. |
| rimLevel | Rim Level | Required. Finite number. |
| Output field | Interpretation | Returned shape |
|---|---|---|
| freeboard | Freeboard | Required. Finite number. |
json
{
"input": {
"overflowLevel": 99.7,
"rimLevel": 100
},
"output": {
"freeboard": 0.29999999999999716
}
}Limitations and assumptions
- Levels require one datum and length unit; a negative result is retained and no storm storage, drainage capacity, or safe design allowance is established.
- Inputs must satisfy both the field types and the cross-field conditions above. Invalid input causes an error; a successful false flag or documented placeholder is a different result.
- Numeric calculations use binary floating point unless exact decimal-integer arithmetic is explicitly stated. No hidden measurement tolerance or decimal rounding is added; nonfinite or out-of-contract results are rejected. Numeric signed-zero results are exported as zero.
Alternative or Complementary methods
Verify current measurements, future growth, survey datums, and applicable design requirements for the site.
References
Similar or alternative tools
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- Geographic Height Reference Label
Append the supplied height in meters, reference type, and datum to a label.