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.
Quick answer
How is coconut shisha charcoal tested?
By proximate analysis in a laboratory: moisture, volatile matter and ash are each measured, and fixed carbon is calculated by difference, to ASTM D1762-84(2021). Calorific value is measured in a bomb calorimeter. Burn time and ash color are observed, not measured in a laboratory. An independent laboratory report ships with every container.
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 — ash content, moisture, fixed carbon, volatile matter, every container
- Methods
- ASTM D1762-84(2021)
- Reports per order
- Certificate of Analysis + third-party laboratory report
1. 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.
Proximate analysis measures three parameters in turn and derives the fourth:
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Step 1
Measure moisture by oven-drying
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.
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Step 2
Measure volatile matter without air
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.
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Step 3
Burn the sample to ash
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.
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Step 4
Calculate fixed carbon by difference
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.
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.
What this value means: what calorific value means for heat
| Parameter | Standard | Equipment |
|---|---|---|
| Moisture content | Oven-dry method | Drying oven or moisture analyzer and analytical balance |
| Volatile matter | ASTM D1762-84(2021) | Furnace, covered crucible, and analytical balance |
| Ash content | ASTM D1762-84(2021) | Muffle (ash) furnace and analytical balance |
| Fixed carbon | By difference, ASTM D1762-84(2021) | Furnace and analytical balance (proximate analysis) |
| Calorific value | Not yet confirmed with either laboratory | Bomb calorimeter and analytical balance |
2. 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
3. Independent and third-party testing
Beyond in-house quality control on every batch, Mulia Charcoal commissions independent verification. A third-party laboratory — Carsurin — 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.
To check a sample yourself before you order, use our five-check sample test protocol.
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 classification it relates to is explained under the UN 1361 dangerous-goods classification.
Testing methods — frequently asked questions
How is ash content tested?
How is burn time measured?
How is calorific value determined?
What standards do you test to?
Sources
- ASTM D1762-84(2021) Standard Test Method for Chemical Analysis of Wood Charcoal (opens in new tab), ASTM International
- Guidelines for the Safe Carriage of Charcoal in Containers (September 2024) (opens in new tab), Cargo Incident Notification System (CINS) — accessed