This page sits under Mulia Charcoal's shisha charcoal quality standards pillar. It owns the laboratory procedure behind each figure; what each parameter means and what a good value is is covered on the specifications-explained page, linked at each method.
Testing at a glance
Which parameters are tested, by whom, to what methods, and what report ships with the order.
- Parameters tested
- Ash, fixed carbon, moisture, volatile matter, calorific value (lab); burn time and ash color (observed)
- In-house lab
- Yes — quality control on every batch
- Third-party lab
- Carsurin, Beckjorindo, SGS — ash content, moisture, fixed carbon, volatile matter, every container
- Methods
- ASTM D1762-84(2021), ISO 18125:2017
- Reports per order
- Certificate of Analysis + third-party laboratory report
Laboratory test methods (Tier A)
Each parameter below is produced by a defined laboratory procedure. Where Mulia Charcoal tests to a recognized standard, it is named; where a procedure is described generically, no specific standard is asserted.
Ash content
Ash content is measured by combusting a weighed sample in a furnace until only non-combustible mineral residue remains, then weighing that residue and expressing it as a percentage of the original sample mass.
Standard: ASTM D1762-84(2021)
Equipment: Muffle (ash) furnace and analytical balance
What this value means: what ash content means for your session
Fixed carbon
Fixed carbon is determined by proximate analysis: moisture, volatile matter, and ash are each measured, and fixed carbon is calculated as the remainder by difference. It is not weighed directly — it is what is left once the other three are accounted for.
Standard: ASTM D1762-84(2021)
Equipment: Furnace and analytical balance (proximate analysis)
What this value means: what fixed carbon means for heat output
Moisture content
Moisture is measured by the oven-dry method: a weighed sample is dried at a controlled temperature until its mass stops falling, and the mass lost to evaporation is reported as the moisture content.
Equipment: Drying oven or moisture analyzer and analytical balance
What this value means: what moisture means for lighting and shipping
Volatile matter
Volatile matter is measured by heating a sample in a covered crucible without air for a set time, so the gases driven off burn away; the mass lost (after subtracting moisture) is the volatile matter. It is the volatile-matter step of the same proximate analysis that yields fixed carbon.
Standard: ASTM D1762-84(2021)
Equipment: Furnace, covered crucible, and analytical balance
What this value means: what volatile matter means for smoke and odor
Calorific value
Calorific value is determined in a bomb calorimeter: a weighed sample is fully combusted in oxygen inside a sealed vessel, and the heat released is measured from the temperature rise of the surrounding water, then expressed per kilogram.
Standard: ISO 18125:2017
Equipment: Bomb calorimeter and analytical balance
What this value means: what calorific value means for heat
Observed performance indicators (Tier B)
These are read under defined conditions, not measured to a laboratory standard. They are honest performance indicators — never assigned an ISO or ASTM method.
Burn time
Burn time is observed under defined session conditions — a set cube size, a consistent heat source, and a standard bowl setup — and timed until the coal no longer delivers usable heat. It is a performance indicator, not a standardized laboratory measurement, and is never assigned an ISO or ASTM method.
What this value means: what burn time means in practice
Ash color
Ash color is assessed visually after a coal burns out, against consistent lighting. A light, uniform ash is read as a sign of low mineral content and complete combustion. Like burn time, it is an observed indicator, not a laboratory measurement.
What this value means: what ash color indicates
Independent and third-party testing
Beyond in-house quality control on every batch, Mulia Charcoal commissions independent verification. A third-party laboratory — Carsurin, Beckjorindo, or SGS — tests ash content, moisture, fixed carbon, volatile matter on every container, and that report travels with the cargo so the buyer can confirm the specifications against an outside source.
Separately, the Self-Heating Test (UN Test N.4) is the laboratory procedure that measures whether a substance is liable to self-heating. Since IMDG Amendment 42-24 a passing result no longer exempts UN 1361 charcoal from dangerous-goods carriage.
The test and the classification it supports are covered on the certifications and test reports page and how the classification it supports works is covered under the UN 1361 dangerous-goods classification.