Mist Coverage Calculator

Calculator Inputs

Project name

Used in exports and internal reporting.

Units

Calculations standardize to metric internally.

Nozzles (count)

Total nozzles feeding the target zone.

Length (m)

Provide Length & Width or use Area Override.

Width (m)

Rectangular approximation for the site zone.

Area override (m²)

Use for irregular shapes or measured zones.

Flow per nozzle (L/min)

From nozzle datasheet at working pressure.

Coverage radius (m)

Effective radius at target mounting height.

Spray pattern

Choose a conservative shape for planning.

Spray angle (degrees)

Used only for rectangular approximation.

Overlap allowance (%)

Accounts for intentional overlap and edge losses.

Wind factor (0.40–1.00)

Lower values reduce effective coverage in wind.

Height factor (0.40–1.00)

Adjust for mounting height and spray breakup.

Operating hours/day

Used for daily water and cost estimates.

Water cost (per m³)

Enter your local blended water + pumping cost.

Target coverage (%)

Used to recommend nozzle count.

Results appear above this form after submission.

Formula Used

Area and coverage

Site Area = Length × Width, or Area Override.
Base Area/Nozzle = π·r² (circular) or angle-based rectangle.
Unique Area/Nozzle = Base × (1 − Overlap) × Wind × Height.
Total Coverage = Unique Area/Nozzle × Nozzles.
Coverage % = (Total Coverage ÷ Site Area) × 100.

Water and cost

Water (L/h) = Flow(L/min) × Nozzles × 60.
Water (L/day) = Water(L/h) × Hours/day.
Depth (mm/h) = Water(L/h) ÷ Site Area(m²).
Cost/day = (Water(L/day) ÷ 1000) × Cost per m³.
Recommended Nozzles = ceil(Target Area ÷ Unique Area/Nozzle).

Note: Factors help planning. Validate final design with field tests and nozzle datasheets.

How to Use This Calculator

Enter the zone size using Length and Width, or Area Override.
Set nozzle count, flow rate, and effective coverage radius.
Choose pattern and angle if you need a conservative projection.
Adjust overlap, wind, and height factors to match site conditions.
Click Calculate, then export CSV or PDF for documentation.

Coverage planning assumptions

This calculator estimates effective misted area using nozzle radius and a practical loss model. Base coverage is computed per nozzle, then reduced by overlap allowance and two correction factors. Wind factor represents drift and reduced wetting at the edge of the plume. Height factor reflects mounting height, breakup, and throw efficiency. Treat results as planning values and confirm performance with field observations. Record nozzle type, pressure, and spacing so teams can reproduce settings across shifts and similar zones.

Selecting nozzle radius and spacing

Use the radius that matches your operating pressure and mounting height from the nozzle datasheet. If you are spacing nozzles on a line, start with spacing near one radius and increase only after testing. Higher overlap improves uniformity but reduces unique coverage. For irregular zones, enter a measured area override to avoid underestimating water needs.

Managing drift and overspray

Drift control matters for safety, neighbor impacts, and material protection. Lower the wind factor when gusts or crosswinds are common, and consider physical shields or relocating headers to sheltered sides. Increase overlap slightly to reduce dry gaps caused by shifting plumes. If overspray is a concern, reduce radius, switch to a tighter pattern, or limit operating hours.

Water demand and supply checks

Water demand is calculated as flow per nozzle multiplied by nozzle count and runtime. The report also converts hourly water to application depth in millimeters per hour, which helps compare against dust control targets and surface tolerance. Verify that storage, pumps, and piping can support peak flow. Add a safety margin for start up flushing and pressure variations.

Cost, documentation, and compliance

Daily operating cost uses total water per day and your unit water cost per cubic meter, supporting quick budget reviews. Use the target coverage setting to estimate a nozzle count that meets your desired coverage threshold. Export CSV for estimating sheets and PDF for site files. Keep records of weather, shift hours, and adjustments to support audits and performance reviews.

FAQs

What radius should I enter?

Use the effective radius from the nozzle datasheet at your operating pressure and mounting height. If field conditions reduce throw, enter a smaller radius and adjust wind and height factors accordingly.

How do I choose overlap allowance?

Start with 15% to 30% for uniform wetting and edge loss control. Increase overlap when you see dry stripes or shifting plumes, and reduce it when water use is too high.

What wind factor values are practical?

Use 0.90 to 1.00 for calm or sheltered areas, 0.75 to 0.89 for moderate wind, and 0.40 to 0.74 for windy edges. Always verify with on site observation.

Why is coverage capped at 100%?

Coverage percent represents how much of the site area can be reached at least once. Over coverage may improve uniformity, but it cannot exceed the total site area for reporting.

How is application depth calculated?

Hourly water use in liters is divided by site area in square meters. Because 1 liter per square meter equals 1 millimeter, the result is shown as millimeters per hour.

Can I export results for reports?

Yes. Run a calculation, then use Download CSV for spreadsheets or Download PDF for a quick text report. Exports use the latest saved result from your session.

Example Data Table

Scenario	Area (m²)	Nozzles	Flow (L/min)	Radius (m)	Overlap	Wind	Height	Coverage %	Water (L/h)
Dust control lane	1000	12	1.6	4.0	20%	0.85	0.90	≈ 46%	1,152
Cooling zone	600	16	1.2	3.5	25%	0.90	0.95	≈ 79%	1,152
High wind edge	800	18	1.4	4.0	20%	0.70	0.90	≈ 71%	1,512

Examples are illustrative. Your results depend on factors and nozzle data.