A record needs more than a model and a number

Air Tool Match admits a figure only when a manufacturer-owned page identifies the model, publishes the airflow value, states the relevant pressure, and makes the field's meaning clear enough to preserve. Every accepted row keeps the source URL and the date it was checked.

The site does not copy a bare CFM number into a general product database. It stores a small evidence bundle:

  • Manufacturer and exact model identifier.
  • Product or tool category.
  • Published value and unit.
  • The manufacturer's field wording.
  • Stated PSI.
  • Manufacturer-owned source URL.
  • Checked date.

Tool records may also keep separate average and load-consumption fields. Compressor records keep the published output label so the matcher can distinguish CFM from labels it does not currently combine, such as SCFM delivered.

The admission source

The default source is the manufacturer's own model page or technical document. A retailer page, forum answer, search snippet, or copied chart may point toward a missing field, but it does not become the stored specification merely because it supplies a convenient number.

That rule prevents a common provenance error. A retailer may display an air-consumption figure that the current manufacturer page does not publish. Repeating the retailer's value as if the manufacturer stated it would erase the difference between those sources.

When the manufacturer page is silent, the record stays incomplete. The article on missing manufacturer air-consumption fields explains why the site treats silence as a real result.

The source rule is not a claim that manufacturer pages never contain mistakes. It gives each value a traceable origin and lets a reader inspect the same publication the record keeper saw.

The transcription rule

A figure is copied with its context rather than normalized into whatever wording fits the table.

For a compressor, these two entries are not stored as identical labels:

Performance (90 PSI): 4.2 CFM
3.0 SCFM delivered @ 90 PSI

Both have a number and a pressure. One is categorized as CFM in the current data; the other retains SCFM delivered. The site shows both records, but its current comparison method does not subtract the second from a tool's CFM figure.

For a tool, average consumption and consumption at load remain separate fields. If a page publishes only consumption at load, the average field is null. The site does not divide, estimate, or borrow a ratio from another model.

What makes two stored figures eligible for arithmetic

Admission to the directory and eligibility for a comparison are different decisions. A record can be useful and correctly sourced even when the matcher refuses to combine it with the selected counterpart.

The current comparison requires:

  1. A selected tool field that the manufacturer publishes.
  2. A compressor record categorized as CFM.
  3. The same stated PSI on both records.
  4. A whole-number tool quantity from 1 through 20.

When those checks pass, the calculation is deliberately small:

published tool CFM × selected quantity = displayed tool demand
published compressor CFM − displayed tool demand = displayed difference

The words demand and difference describe the arithmetic in the interface. They do not turn the result into a compressor-sizing method or a performance guarantee.

Quantity does not prove simultaneous operation

The quantity field multiplies one published tool value by the number entered. Selecting three identical tools with a published average figure of 4.2 CFM produces:

4.2 CFM × 3 = 12.6 CFM

That is a calculation, not an observation that three tools will run together or that the compressor can support them. Simultaneous use depends on operating pattern, duty cycle, distribution, receiver behavior, pressure losses, and other conditions absent from the stored records.

The result therefore says what was multiplied and which field was selected. It leaves the equipment conclusion to a source or professional that can account for the actual system.

Why the matcher abstains

An abstention is a designed output. It occurs when the site cannot support the subtraction without hiding a source difference.

The requested tool field is missing

Some tool pages publish load consumption but not average consumption. If a visitor selects average consumption for that model, the site says the source does not publish the figure. It does not silently fall back to the load value.

The pressure conditions differ

A tool value at 90 PSI does not match a compressor value at 40 PSI. Even if both use CFM, the site stops because the pressure attached to the figures differs.

The labels do not fit the current rule

The current utility does not convert or merge CFM, SCFM, ACFM, displacement CFM, or delivered-SCFM categories. A compressor row with an unlike label stays visible in the directory with its source, but the matcher returns not comparable.

The source context is unclear

A number without a clear model, unit, pressure, or field meaning is not admitted until the manufacturer source resolves the missing context.

Checked dates and maintenance

Every row has a checked date because product pages change. The date means someone read the linked page and transcribed the shown field on that day. It does not promise that the page will remain unchanged.

A record needs review when:

  • Its manufacturer URL stops resolving or redirects to an unrelated page.
  • The model page changes the value, unit, pressure, or label.
  • A previously missing field appears.
  • The site's comparison contract changes.
  • A visitor reports a specific discrepancy that can be checked against a primary source.

An update should change the stored row, checked date, and any article example that depends on it. The old value belongs in Git history, not beside the current value as an unexplained duplicate.

Why the directory includes non-comparable records

Removing every row the matcher cannot subtract would hide useful evidence about the market's actual labeling. A visible SCFM-delivered row shows why the site stopped. A visible missing average field shows that the refusal came from the source record, not a broken form.

The records directory therefore serves two jobs: it exposes the data behind successful comparisons and makes abstentions inspectable. It is not a shopping chart, and it contains no paid ranking or preferred manufacturer.

What the method does not verify

Source accuracy and calculation accuracy do not settle equipment suitability. The current record does not describe receiver condition, recovery, duty cycle, regulator behavior, hose size or loss, ambient conditions, electrical supply, installation, simultaneous-use timing, or pressure safety.

Air Tool Match also does not test the physical products. It reports and compares published fields under a narrow contract. For a purchase, installation, or operating decision, verify the complete application with the manufacturers or a qualified professional.

Audit a record yourself

Open any row in the records directory, follow the manufacturer link, and check four items: model, field wording, value and unit, and stated pressure. The checked date tells you when the site last performed that same reading.

If one of those items no longer matches, the record needs review. Until it is corrected, the source page takes precedence over this site's transcription.