Salt Spray Chamber for Corrosion Testing

Salt Spray Chamber (also known as Salt Fog Chamber, Salt Spray Tester, or Corrosion Test Cabinet) is a specialized environmental test apparatus used to evaluate the corrosion resistance of materials, coatings, surface treatments, metals, and finished products under accelerated corrosive conditions.

It simulates harsh marine or salty environments by generating a fine mist (fog) of salt water inside a sealed chamber. This is one of the most common and standardized accelerated corrosion tests worldwide.

Primary Applications

Automotive, aerospace, marine, and construction — Testing paints, coatings, platings (zinc, nickel, chrome), fasteners, body panels, etc.
Electronics and electrical components — checking corrosion on connectors, housings, and circuit boards.
Metal finishing and galvanizing industries — evaluating protective layers.
Pharmaceutical and medical devices — Limited but important use for testing corrosion resistance of stainless steel instruments, medical equipment, packaging components, or metallic parts in drug manufacturing equipment (e.g., tablet press dies, filling machine parts) to ensure durability and compliance with hygiene/safety standards.
General quality control and R&D for product durability and shelf-life prediction.

Working Principle

A 5% sodium chloride (NaCl) solution (prepared with distilled/deionized water) is atomized using compressed air through special nozzles.
This creates a dense, corrosive salt fog/mist that settles uniformly on the test specimens.
The chamber maintains a controlled temperature (usually 35°C ± 2°C).
Test specimens are placed at an angle (typically 15°–30° to vertical) so the fog settles evenly without pooling.
Exposure duration can range from 24 hours to 1,000+ hours, depending on the requirement.
After the test, samples are inspected for rust, blistering, pitting, or coating failure. Results are usually comparative (pass/fail or hours to first corrosion).

The test is accelerated — it compresses years of real-world exposure into days or weeks.

Main Types of Salt Spray Tests

NSS (Neutral Salt Spray) → Most common (ASTM B117, ISO 9227) — 5% NaCl, pH 6.5–7.2, 35°C.
AASS (Acetic Acid Salt Spray) → More aggressive (pH 3.1–3.3) for coatings on aluminum or decorative finishes.
CASS (Copper-Accelerated Acetic Acid Salt Spray) → Even harsher (adds copper chloride, 50°C) for high-performance coatings.
Cyclic Corrosion Chambers → Advanced models alternate salt spray with dry/humid phases to better simulate real environments (e.g., ASTM G85).

Key Standards

ASTM B117 — Standard Practice for Operating Salt Spray (Fog) Apparatus (most referenced globally).
ISO 9227 — Corrosion tests in artificial atmospheres – Salt spray tests (NSS, AASS, CASS).
Others: JIS Z 2371, ASTM G85 (modified), GM, Ford, etc.

Typical Specifications of a Salt Spray Chamber

Capacity — 108 L, 270 L, 450 L, 600 L, 1000 L, 2000 L+ (lab to walk-in sizes).
Temperature Range — Ambient to 50°C (or 60°C in some models).
Salt Solution Tank — Separate reservoir (15–50 L or more).
Construction — Usually FRP (fiber-reinforced plastic) or corrosion-resistant materials with viewing window.
Controls — Digital PID controller, touchscreen (in modern models), timer, fog collection funnels.
Features — Pneumatic spray, adjustable spray volume (1–2 mL/h per 80 cm² collection rate), over-temperature protection.

Basic Components

Test chamber with lid
Salt solution reservoir and atomizing nozzle
Air saturator/humidifier
Heater and temperature sensor
Fog collectors (to verify spray rate)
Specimen racks/supports
Drainage and exhaust system

Leading Salt Spray Chamber manufacturer

Accumax India cyclic corrosion chamber products are one of the world’s most modern and adaptable salt spray chamber test equipment, with unrivalled design, ergonomics, and quality. From continuous salt spray tests to condensation humidity and modified tests, cyclic corrosion test chamber products are available to meet every testing need. We are a leading Salt Spray Test Chamber manufacturer in India.