Water activity (aw) quantifies the amount of free water available in a sample for microbial growth, chemical reactions, and enzymatic activity. It is a critical parameter for predicting shelf life and ensuring product safety. The Novasina LabStart‑aw is an entry-level benchtop instrument designed for routine water activity checks in food, cosmetics, and pharmaceutical quality control laboratories. All specifications listed below are based on factory testing under standard conditions.

Key Benefits

Affordable Entry into Water Activity Testing

The LabStart‑aw is designed as a starter instrument for laboratories with moderate accuracy requirements. A small food manufacturer can monitor finished product quality and obtain reliable water activity data without a large capital investment. Similarly, a university teaching laboratory can introduce students to water activity principles using an instrument that is straightforward to operate. For laboratories that require higher precision or advanced features, Novasina offers a full range of water activity solutions within the broader product family.

Proven Resistive Electrolytic Sensor Technology

The proprietary resistive-electrolytic sensor eliminates the memory (hysteresis) effect commonly found in other sensor types and requires only infrequent cleaning. A quality control technician running multiple samples per day can expect consistent results without needing to recalibrate between measurements. When a sensor is eventually replaced, the new sensor retains all factory-calibrated values, so the instrument remains within calibration immediately.

Simple and Intuitive Operation

The large LCD screen features an intuitive menu structure that clearly displays water activity, temperature, and measurement stability. A new operator can become productive after a brief demonstration. The built-in automatic equilibrium detection removes guesswork by signaling precisely when the measurement is complete, eliminating any need for subjective interpretation.

Reusable SAL‑T Standards for Lower Operating Costs

The reusable SAL‑T reference standards, when stored in their supplied airtight containers, can remain stable and usable for several years. A busy QC laboratory performing daily verifications will save significantly on consumable costs compared to instruments that rely on single-use standards. The 75% rH reference salt included with every unit allows immediate performance verification right out of the box.

Compact and Robust Design

Weighing only 1.2 kg and measuring just 225 × 140 × 85 mm, the LabStart‑aw fits comfortably on even a crowded laboratory bench. The two-part PC/ABS housing with IP22 protection is built to withstand the demands of daily routine quality control. The instrument conforms to internationally recognized standards, including AOAC International methods for water activity determination.

Common Challenges — and How the LabStart‑aw Addresses Them

“The instrument costs too much for occasional testing.”

Small laboratories and teaching facilities often cannot justify the expense of high-end water activity meters. The LabStart‑aw provides reliable measurements at an accessible price point, enabling a small food producer to monitor product stability without overinvesting, or an academic laboratory to teach water activity principles without straining the budget.

“The instrument is too complex and requires extensive training.”

Sophisticated instruments with multiple menus and settings can intimidate new users. The LabStart‑aw features a clear, simple interface with a large LC-display and automatic equilibrium detection that signals measurement completion. A quality control technician with basic laboratory skills can operate the instrument confidently after a short demonstration.

“Frequent recalibration and consumable costs add up.”

Some instruments demand daily recalibration and rely on expensive single-use standards. The LabStart‑aw uses reusable SAL‑T standards that remain stable for years when stored properly in their airtight containers. The resistive-electrolytic sensor’s freedom from memory effects means recalibration is infrequent. Operating costs remain predictable and low.

“There is no way to verify whether the instrument is reading correctly.”

Without a reference standard, operators cannot confirm instrument accuracy. The LabStart‑aw ships with a 75% rH SAL‑T reference salt, allowing immediate performance verification. A quality manager can confirm instrument performance before each testing session with confidence.

“Volatile samples contaminate and damage the sensor.”

Samples containing alcohol, acids, bases, or chlorine can degrade the sensor over time. The LabStart‑aw is compatible with optional chemical protection filters that prevent volatile compounds from reaching the sensor, extending sensor life and maintaining measurement accuracy.

Suitable Applications

Food and Beverage Quality Control — Monitor the water activity of breads, cereals, powders, and other drier materials within the recommended 0.20 to 0.80 aw range. The instrument supports routine checks without requiring the complexity of advanced systems.

Pharmaceutical Quality Assurance — Perform water activity testing of excipients and finished dosage forms where moderate precision is acceptable. The instrument is well suited for basic research and quality control workflows.

Cosmetics and Personal Care — Measure the water activity of creams, lotions, and other formulations. The resistive electrolytic sensor handles a wide variety of sample types without issue.

Academic Teaching Laboratories — Introduce undergraduate students to water activity principles. The simple interface and accessible price point make the LabStart‑aw ideal for educational settings.

Agricultural and Environmental Testing — Analyze the water activity of soil, animal feed, and agricultural products. The compact, lightweight design allows easy movement between sampling locations.

Technical Specifications

Model: LabStart‑aw
Part Number: 37910‑06 / NV2600992
Measurement Principle: Electrolytic resistive sensor

Water Activity Parameters

Temperature Parameters

Physical and Electrical Specifications

What Is Included

The LabStart‑aw ships as a complete, ready-to-use kit containing the following items:

• LabStart‑aw water activity measuring instrument (1 unit)
• Sample cups (20 pieces, diameter 30 mm × height 14 mm)
• SAL‑T reference salt: 75% rH (1 unit)
• Factory calibration certificate
• External universal power supply (90–264 VAC, 50/60 Hz)

What Is Not Included

• Data logging capability (not available on this model)
• Chemical protection filters for alcohol, acid, base, or chlorine (available as optional accessories)
• Additional reference salts beyond the included 75% rH standard (33%, 58%, 84%, 97%, and 100% rH available separately)
• Additional reusable SAL‑T standards

Pre-Installation Requirements

Before setting up the instrument, ensure you have the following:

• A stable, level bench or laboratory table
• Ambient temperature between 15–30 °C
• An AC power outlet compatible with 90–264 VAC, 50/60 Hz
• Adequate clearance around the instrument for placement and cable connections

Daily Operation Guide

Installation

Place the instrument on a stable, level bench. Its 225 × 140 × 85 mm footprint fits on a standard laboratory surface. Connect the external power supply to a 90–264 VAC, 50/60 Hz outlet. The instrument is ready for use without any additional setup.

Sample Preparation

Fill a sample cup (diameter 30 mm × height 14 mm, 15 mL capacity) approximately half full. Do not overfill. Place the cup into the measuring chamber.

Measurement

Close the measuring chamber. The instrument equilibrates the sample to ambient temperature (15–30 °C), and the resistive electrolytic sensor measures the water activity. The large LC-display shows water activity, temperature, and stability in real time. The built-in automatic equilibrium detection signals when the measurement is complete.

Verification

Insert the supplied 75% rH SAL‑T reference salt into the measuring chamber. The instrument displays the measured value. Compare it with the expected value to verify instrument performance.

Maintenance

The resistive-electrolytic sensor requires only infrequent cleaning due to its absence of memory effects. When working with samples that contain alcohol, acids, bases, or chlorine, install optional chemical protection filters to protect the sensor. When a sensor no longer meets factory specifications, it can be replaced. The new sensor retains all factory-calibrated values.

Ordering Information

Model: LabStart‑aw

When placing an order, please specify any optional chemical protection filters required for your application.

Optional Accessories

• Chemical protection filters (for alcohol, acids, bases, and chlorine)
• Additional SAL‑T reference salts (available in 33%, 58%, 75%, 84%, 97%, and 100% rH)
• Additional sample cups
• Replacement sensor