Fume extraction airflow calculator
Estimate capture airflow for an open hood or enclosed laser cleaning cell, then check duct velocity, preliminary static pressure and fan shaft power before requesting a final extraction-system design.
- Open hood and enclosure modes
- m³/h and CFM output
- Duct velocity and diameter check
- Preliminary pressure and fan power
Estimate extraction airflow from the actual capture arrangement
Select the open-face method for a hood or partial enclosure. Select enclosure volume for a closed cell with a planned air-change rate.
How airflow, duct size and fan power are estimated
The formulas are visible so your extraction supplier can review the assumptions and replace them with project-specific data.
open area x capture velocity x 3600Calculates cubic meters per hour through the effective hood or partial-enclosure opening.
cell volume x air changes per hourEstimates the airflow needed to reach the selected enclosure air-change rate.
square root of 4Q / (pi x velocity)Returns the theoretical duct diameter at the selected transport velocity.
airflow x static pressure / fan efficiencyEstimates air power at the calculated operating point before motor and drive selection.
Airflow alone does not prove effective fume control
Hood position, cross-drafts, worker location, plume direction, process movement and filter performance determine whether contaminants are actually captured.
Reduce required airflow by controlling the contaminant at its source
A well-positioned partial enclosure often captures more reliably than a large remote hood with much higher airflow.
Keep the plume inside a controlled zone
Use physical panels, curtains or a dedicated cell where the process and part allow it.
- Minimize unnecessary open area
- Keep access doors out of the main airflow path
- Maintain the required pressure relationship
Place capture close to plume travel
Arrange the inlet so contaminated air moves away from the operator and into the hood.
- Observe plume direction during testing
- Review robot and handheld movement
- Avoid pulling fumes through the breathing zone
Protect capture from cross-drafts
Doors, fans, compressed air and vehicle movement can overpower local capture.
- Test under normal production conditions
- Coordinate process gas and compressed air
- Provide adequate make-up air
Design filtration around what the laser actually removes
Base metal, coating chemistry, dirt and process temperature can produce very different particles and gases.
| Removed Material | Potential Concern | Information To Collect | Design Review |
|---|---|---|---|
| Rust and metal oxide | Fine metal-containing particulate | Base alloy, corrosion products and cleaned mass | Particulate filtration, duct transport and disposal |
| Paint or protective coating | Decomposition fumes, pigments and mixed particles | SDS, coating age, layers and possible hazardous constituents | Gas-phase treatment, particulate control and exposure assessment |
| Oil and grease | Condensable aerosol, vapors and duct/filter fouling | Product identity, quantity and temperature behavior | Pre-cleaning, fire risk and suitable filter stages |
| Plated or alloyed surface | Metal-specific toxicology and fine particulate | Complete material composition and coating thickness | Industrial-hygiene review and appropriate filtration |
| Unknown legacy coating | Uncharacterized hazardous material | Sampling, laboratory identification and site history | Do not rely on a generic airflow estimate alone |
Size the fan at the required operating point
Catalog free-air airflow is not the airflow delivered after ducts, fittings and loaded filters create resistance.
Select the fan so it can maintain capture as filters load toward the approved change point.
Ask the supplier to show fan performance at the calculated airflow and total static pressure.
Motor power, energy use and heat depend on the actual fan operating point and drive efficiency.
Differential-pressure indication helps operators identify loading, blockage and maintenance needs.
Some collected dusts, fibers, oils and coating residues may require spark, fire or explosion protection.
Collected material and spent filters may require controlled handling based on their composition.
Validate capture after the extraction system is installed
Confirm performance during the real cleaning process, with normal part positions, operator movement and filter condition.
Measure airflow and duct velocity
Use calibrated instruments and approved traverse locations rather than relying only on fan settings.
Visualize plume capture
Use a safe approved visualization method to check escape near hood edges, doors and operator positions.
Test normal cross-drafts
Repeat checks with doors, ventilation, compressed air and nearby production equipment in normal operation.
Confirm enclosure pressure
Verify airflow direction through openings and make-up air paths without creating unsafe access or process conditions.
Review exposure evidence
Use industrial-hygiene monitoring where needed to confirm worker exposure is adequately controlled.
Record clean and loaded pressure
Document baseline pressure, alarm levels, filter-change criteria and inspection frequency.
Match laser cleaning and fume control before production
Share the part, base material, contaminant, process video and intended work area. Oceanplayer can help your extraction specialist understand the cleaning process and machine configuration.
Identify the material
Base metal, coating, oil, rust, SDS and unknown legacy layers.
Define the process
Cleaner type, power, scan width, movement, duty cycle and work area.
Validate the control
Coordinate capture testing, filtration and exposure review with specialists.
Continue planning the complete laser cleaning system
Compare process feasibility, machine power, production capacity and site electrical demand.
Laser cleaning fume extraction questions
Practical answers for early airflow, duct and filtration planning.