A pneumatic rock drill noise report is useful only when the number is tied to a named test method, a fully identified drill configuration, declared operating conditions, microphone positions and a traceable result. A bare value such as “98 dB” cannot tell a buyer whether it is sound pressure or sound power, where it was measured, whether uncertainty is included, or whether two suppliers used comparable tests. Use laboratory noise data to compare declared products and plan due diligence—not as a substitute for a workplace noise assessment.
For hand-held non-electric power tools, ISO 15744 is a recognized noise-measurement code. Its title identifies an engineering method for hand-held non-electric power tools. The buyer still has to check that the reported drill, mounting, consumable, supply and operating cycle match the quoted equipment. Model-specific manuals, contractual requirements and local occupational-noise rules remain controlling.
What a buyer should ask for
Ask for the complete report or a controlled test summary, not a marketing table copied into a quotation. At minimum, the document should let a reviewer answer five questions: what was tested, how it was operated, where sound was measured, what quantity was reported, and who performed the work.
| Report item | Why it matters | Buyer check |
|---|---|---|
| Method and edition | Defines the measurement framework and prevents two unrelated procedures being treated as equivalent. | Record the complete reference, edition or adoption, and any stated deviations. |
| Tool identity | Noise can change with model, mass, air system, muffler, chuck, air leg and condition. | Match model, drawing revision, serial or sample ID, and fitted accessories to the offer. |
| Operating condition | Air pressure, drilling medium, drill steel, bit, feed and flushing affect the acoustic event. | Require actual tool-inlet pressure under operation and a description of the test task. |
| Acoustic quantity | Sound pressure and sound power answer different questions and are not interchangeable. | Demand the symbol, weighting, units, measurement position and whether the value is measured or declared. |
| Variability and uncertainty | A single rounded number hides repeatability and measurement limits. | Ask for repeat count, result spread and the uncertainty or declaration convention used. |
| Laboratory traceability | Traceability makes the result reviewable and repeatable. | Check report number, issue date, signatory, equipment calibration and laboratory identity. |
Sound pressure, sound power and exposure are not the same
Emission sound pressure level
An emission sound pressure level describes sound at a specified measurement position under the test arrangement. It is not a universal operator-ear value. Distance, room reflections, microphone orientation, operating surface and the presence of other sources can change a field measurement. A supplier must therefore state the position and method rather than presenting “dB” alone.
Sound power level
Sound power characterizes acoustic energy emitted by the source under defined conditions. It is useful when comparing machines tested consistently, but it is not the level that a worker automatically receives at the ear. Converting a declared power value into a site exposure requires information about the workplace, distance, reflections, barriers, operating time and other equipment.
Daily personal noise exposure
Exposure combines level and duration across the working day. The UK Health and Safety Executive’s Controlling Noise at Work guidance treats equipment information as one input to risk assessment and equipment selection. NIOSH likewise explains that risk depends on how loud the sound is, how long it lasts and how often it repeats. Its occupational guidance uses an 85 dBA eight-hour recommended exposure limit and a 3 dB exchange rate; local legal limits may differ. Procurement data cannot replace competent measurement of the actual work cycle.
Read the operating conditions before comparing numbers
Noise from a pneumatic rock drill comes from several paths: piston impact, drill-steel and rock interaction, exhaust air, rotation and chuck contact, hoses and fittings, and the surrounding space. A report that omits the operating condition prevents a buyer from deciding which sources were represented.
| Variable | What the report should record | Comparison risk if missing |
|---|---|---|
| Air supply | Supply arrangement and pressure at the tool while running; flow information if required by the method or specification. | A no-load gauge pressure can conceal pressure loss and an unrepresentative operating point. |
| Drill setup | Hand-held or air-leg configuration, air-leg model and feed setting, if applicable. | Different restraint and feed conditions may alter impact transfer and radiated sound. |
| Drill steel and bit | Shank, steel length, bit type and diameter, plus condition of the consumables. | Ringing, fit and rock contact may differ even when the drill body is identical. |
| Test medium and task | Workpiece or rock description, fixture and whether the tool was drilling, impacting or running without load. | No-load and loaded results do not represent the same acoustic event. |
| Flushing | Dry, air-flush or water-flush condition and relevant connections. | A different flushing arrangement changes both the configuration and background sources. |
| Tool condition | New, run-in or serviced status; fitted muffler or exhaust treatment; lubrication arrangement. | Wear, leakage, lubrication and exhaust components may influence the result. |
| Environment | Room or field, background noise, reflecting surfaces and any correction described by the method. | Room effects can make a result unsuitable for direct comparison. |
Do not invent an acceptance limit after bids arrive. State in the RFQ which quantity is required, the applicable method, the evidence format and how deviations will be handled. If the project has a contractual noise target, the purchaser’s acoustic specialist should define the test and acceptance rule before sampling.
How to audit an ISO 15744 claim
- Confirm scope. Check that the referenced standard is being used as a noise-measurement code for the offered class of hand-held non-electric tool. Do not treat the phrase “ISO tested” as sufficient.
- Match the tested sample to the quotation. Compare model, configuration, accessories and revision. A report for a related family member is supporting information, not automatic proof for another model.
- Trace the operating point. Look for loaded tool-inlet pressure and the actual task. If the report states only compressor pressure, request clarification.
- Identify every reported quantity. Separate emission sound pressure, sound power and peak values. Confirm frequency weighting, units and positions.
- Review the measurement chain. The report should identify microphones and analyzers, calibration status, background checks and the test organization.
- Examine repetitions and uncertainty. Ask how many runs or specimens were measured, whether the stated value includes an uncertainty allowance, and how the declared value was formed.
- Record deviations. A deviation may be technically reasonable, but it must be explicit. Decide whether it prevents comparison or requires a witnessed repeat test.
A practical comparison table for procurement
Normalize every offer into one review sheet. Leave a cell blank when evidence is absent; do not fill it with a verbal assurance. This makes incomparability visible before price evaluation.
| Comparison field | Supplier A | Supplier B | Decision rule |
|---|---|---|---|
| Test method and edition | Record exactly | Record exactly | Same or technically reconciled |
| Tested model/configuration | Model, air leg, muffler | Model, air leg, muffler | Must match the offered configuration |
| Loaded inlet pressure | Value and location | Value and location | Comparable operating point |
| Task and workpiece | Describe | Describe | Comparable acoustic event |
| Emission sound pressure | Value, weighting, position | Value, weighting, position | Compare only like with like |
| Sound power | Value and declaration basis | Value and declaration basis | Compare only like with like |
| Uncertainty/variability | State | State | Include in technical judgment |
| Report traceability | Number, date, lab | Number, date, lab | Complete and reviewable |
Red flags in supplier noise data
- A number without a quantity: “dB” is shown, but the report does not say sound pressure, sound power or peak.
- No operating description: pressure, drill steel, bit, feed and workpiece are absent.
- Catalog reuse: the model or revision on the report differs from the offered drill.
- Impossible certainty: one precise value is shown without repetitions, spread or uncertainty information.
- Mixed test methods: suppliers cite different procedures, yet the values are ranked directly.
- Exposure claim from laboratory data: the seller presents an emission number as proof that a complete work shift is safe.
- Untraceable screenshot: there is no report number, issue date, laboratory identity or signed approval.
RFQ wording buyers can adapt
Request a noise-emission report for the exact offered pneumatic rock drill configuration. Require the complete test method and edition; sample identity; air-leg, muffler and accessory configuration; drill steel and bit; loaded tool-inlet pressure; test medium and task; microphone positions; reported acoustic quantities and weightings; repetitions; uncertainty or declaration basis; test equipment calibration traceability; report number; date; and authorized signatory. State that non-equivalent methods or configurations must be declared before bid closing.
For a commercially supported reference, review the PerfoMax YT28 air-leg rock drill. Its page deliberately treats published figures as a reference configuration and requires final quotation data to be confirmed. For component terminology and the limits of model-to-model assumptions, see pneumatic rock drill anatomy and working principle.
Frequently asked questions
Does an ISO 15744 report prove the drill is safe for an eight-hour shift?
No. It provides controlled noise-emission data under a defined method. Worker exposure depends on actual sound levels, operating duration, repetition, distance, reflections, other equipment and controls. Use site measurements and the applicable local occupational-noise rules.
Can I compare two values if both suppliers write “dB(A)”?
Not yet. Confirm that both values describe the same acoustic quantity, operating condition, measurement position, test method and declaration basis. A-weighting alone does not make the results comparable.
Why request sound power when operators are concerned about sound at the ear?
Sound power supports source comparison under consistent conditions, while sound pressure is position- and environment-dependent. Neither by itself predicts a worker’s daily exposure. A sound procurement review keeps the quantities separate and uses each for its intended purpose.
Is a report for another model in the same drill family acceptable?
It can be background evidence, but it should not be treated as the declaration for the offered model without a documented technical justification. Configuration changes in mass, exhaust treatment, air leg, shank, steel or operating point may affect noise.
Should a buyer set a universal pass/fail decibel limit?
No universal limit should be invented from unrelated catalogs. Define the project objective, jurisdiction, quantity, method, configuration and uncertainty rule first. When the requirement is safety-critical, involve a qualified occupational-noise specialist.
Build a comparable evidence pack before ordering
Keep emission evidence separate from the site risk calculation. Use the pneumatic rock drill noise-exposure guide for LEX,8h, trigger-time and multi-source calculations, and review the available pneumatic rock drill range when preparing the RFQ.
Send PerfoMax the offered model, intended air-leg or hand-held configuration, working pressure, drill steel and bit, drilling application, destination market and your required noise-document format. We can align the quotation and available evidence to the same configuration, identify gaps and separate laboratory emission data from site-exposure obligations. Request a configuration review for the YT28 air-leg rock drill.
Technical references: ISO 15744:2002, Hand-held non-electric power tools—Noise measurement code—Engineering method (grade 2); UK HSE, Controlling Noise at Work (L108, third edition); NIOSH, Noise-Induced Hearing Loss. Verify contractual standards, editions and local legal requirements for the destination market.