Moisture Analysers: Why They Do Not Measure Water, and When That Matters
- Aug 20
- 4 min read
Updated: 3 days ago
Key takeaways
A moisture analyser does not measure water — it measures every substance that leaves your sample when heated, and reports the total as moisture. That is why the number it gives you is not the same as water content, and why it matters the moment your sample contains volatile oils, residual solvent or anything heat-labile.
It replaces the oven, not the reference method. A halogen analyser gives you in minutes what loss on drying gives you in hours, but only after you have correlated it against your oven result. Out of the box it will not match.
If you need water specifically, you need Karl Fischer. Different instrument, different price band, different answer.
Our OHAUS MB range runs £1,824.00 to £4,118.25, or ₦3,351,328 to ₦7,566,672.
What is a moisture analyser?
A moisture analyser is a precision balance with a heating element above the pan. It weighs the sample, heats it until the mass stops changing, and reports the percentage of mass lost.
That is the entire principle, and understanding it explains both the strength and the limitation of the technique.
The strength: it is fast, it needs no reagents, it requires almost no training, and it produces a result in minutes on the bench where the sample is.
The limitation: mass loss is mass loss. The instrument has no way to know what left the sample. Water, ethanol, essential oils, residual process solvent and decomposition products all register identically.
The technique is properly called thermogravimetric moisture determination, and it is a direct automation of the classical loss-on-drying method.The weighing side of that instrument follows the same rules as any other laboratory balance so the class you would need on the bench is the class you need here.
Moisture analyser, oven or Karl Fischer?
Moisture analyser | Drying oven | Karl Fischer titration | |
What it measures | Total volatiles | Total volatiles | Water, specifically |
Time per sample | 3–15 minutes | 2–16 hours | 3–10 minutes |
Sample size | 5–10 g typically | 5–50 g | Milligrams to grams |
Reagents | None | None | Yes, ongoing cost |
Detection range | Roughly 0.1% upward | Roughly 0.1% upward | Down to parts per million |
Good for | Food, feed, grain, soil, plastics, pharma in-process | Reference method, bulk samples | Solvents, oils, APIs, low water content |
Fails on | Volatile oils, residual solvent, heat-labile samples | Same, plus it is slow | Nothing, but it costs more per sample |
UK price | £1,824–£4,118 | £1,881–£4,324 | £4,073 upward |
Nigeria price | ₦3.35m–₦7.57m | ₦3.46m–₦7.94m | ₦7.48m upward |
Naira figures are converted at the rate shown on our store and exclude duty and clearance. Request a landed quote for Nigeria.
When to Use Water content above roughly 1% and the sample contains nothing volatile except water: a moisture analyser. This is most food, feed, grain, soil and many plastics.
Water content below 1%, or the sample contains solvents or volatile oils: Karl Fischer. Our Karl Fischer titration guide covers volumetric against coulometric and where the crossover sits.
Bulk samples, no urgency, or the reference method is specified: the drying oven.
The range, with UK and Nigeria prices
All OHAUS MB series, halogen heating. Prices current at the time of writing.
Model | SKU | UK price | Nigeria price |
30303303 | £1,824.00 (was £2,810.00) | ₦3,351,328.62 | |
30971922 | £1,833.50 (was £1,930.00) | ₦3,368,783.45 | |
30971923 | £2,384.50 (was £2,510.00) | ₦4,381,163.97 | |
30971924 | £3,078.00 (was £3,240.00) | ₦5,655,367.04 | |
— | £4,118.25 (was £4,335.00) | ₦7,566,671.64 |
Naira figures are converted at the rate shown on our store and exclude duty and clearance. Request a landed quote for Nigeria.
Accessories and alternatives
Item | Detail | UK price | Nigeria price |
For MB35 and MB45, SKU 11113873 | £55.10 | ₦101,238.05 | |
75 L, stainless interior, ME/75/TDIG/SS | £1,881.00 | ₦3,456,057.64 | |
SKU HI-904-02 | £4,073.51 | ₦7,484,468.55 | |
Moisture content, AP0014.KF1121 | £954.00 | ₦1,752,833.06 |
Naira figures are converted at the rate shown on our store and exclude duty and clearance. Request a landed quote for Nigeria.
If your samples are large, numerous, or the reference method is specified, the oven route remains valid. It is slower, but it handles bulk that will not fit on a 90 mm pan. For water content specifically, and for low levels a thermogravimetric method cannot reach, the Karl Fischer titrator is the correct instrument.
Frequently asked questions
Is a moisture analyser accurate? It is repeatable and fast. Whether it is accurate depends on whether loss on drying is what your specification actually requires, and on whether your method has been correlated against a reference. The instrument is rarely the limiting factor; the method and the sampling are.
How long does a moisture analysis take? Typically 3–15 minutes depending on sample and method, against 2–16 hours for an oven determination. That difference is the entire commercial case for the instrument.
Can a moisture analyser replace Karl Fischer titration? Not where water content specifically is required, and not at low levels. Karl Fischer reaches parts per million and responds only to water. A moisture analyser typically works from around 0.1% upward and responds to everything volatile.
What temperature should I dry at? Start from the temperature your existing oven method uses and adjust from there. Higher is faster but risks driving off non-water volatiles or decomposing the sample.
Why do my moisture analyser results not match my oven results? Because they will not, until you correlate them. Different drying rates, different end points and different sample presentation all shift the result. That correlation work is expected, not a fault.
How much sample do I need? Typically 5–10 g spread evenly and thinly across the pan. An even layer matters more than the exact mass, because a heap dries from the outside in and triggers the end point early.
Is a moisture analyser the same as a moisture balance? Yes. The terms are used interchangeably, and both describe a balance with a heating element above the pan.
How much does a moisture analyser cost in Nigeria? Between ₦3,351,328 and ₦7,566,672 at the current conversion, excluding duty and clearance. Contact our Lagos office for a landed quote.
Sources and standards referenced
Loss on drying as a gravimetric determination of volatile content, the classical method that thermogravimetric moisture analysis automates.
USP <731> Loss on Drying and USP <921> Water Determination, for the distinction between loss on drying and specific water determination in pharmaceutical practice.
Manufacturer specifications for heating method and model range, as published on the product pages cited.
Product prices and SKUs from the LS Scientific catalogue, verified 6 August 2026. Naira conversion at 1 GBP = 1,837.3512 NGN, 20 August 2026.
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