Physical Address
304 North Cardinal St.
Dorchester Center, MA 02124
D3070-18 – Standard Test Method Technical Guide
🧪 Apparatus and Test Setup
This practice specifies a rapid pressure determination setup utilizing a stainless steel pressure gage with a range of 0 to 160 psi (0 to 1.1 MPa) and preferably one-number graduations.
The gage must be attached to a ⅛-in. Hoke needle valve with leak-proof connections. An adapter is required to fit the specific aerosol valves on the cans under test. A constant-temperature water bath, accurate to ±1°F (±0.5°C), is also necessary for conditioning the samples.
🔬 Leak Prevention: Ensure there are no leaks in the gage apparatus. This can be periodically verified by submerging the attachment in water during a measurement.
The gage apparatus requires specific maintenance:
- Daily Cleaning: Clean by repeated injection and venting of an approved cleaning solution containing a bacteriastat. Rinse with clean water and purge with the pressurizing gas.
- Product Switching: For nonfood products, clean between uses by forcing suitable solvents into the gage and venting. Repeat several times.
⚠️ Cross-Contamination Hazard: When changing between chlorinated solvents and water-base products (or vice versa), thorough cleaning is particularly important to avoid contamination. Use a separate gage apparatus for food products only.
| 🟦 Component | 📏 Specification | 🎯 Detail |
|---|---|---|
| Pressure Gage | 0 to 160 psi (0 to 1.1 MPa) | Stainless steel, one-number graduations |
| Valve Assembly | ⅛-in. Hoke needle valve | Leak-proof connections required |
| Water Bath | ±1°F (±0.5°C) accuracy | Constant-temperature type |
⚙️ Procedure and Pressurizing Gas Selection
The selection of the pressurizing gas depends on the product type. Normal production or laboratory samples are used for this test.
| 🟦 Product Type | 📐 Recommended Gases | ⚡ Notes / Restrictions |
|---|---|---|
| Nonfood Products | Carbon Dioxide (CO₂) Compressed Air Nitrogen (N₂) |
— |
| Food Products | Carbon Dioxide (CO₂) Nitrogen (N₂) Nitrous Oxide (N₂O) |
Compressed air is not recommended due to oxygen content. Gases must not be liquefiable at test conditions. |
Cleaning Protocol: For nonfood products, the gage apparatus may be cleaned between uses by forcing suitable solvents into the gage and venting. This should be repeated several times to ensure the gage is free of contamination.
📊 Significance, Sampling, and Calibration
This practice is intended for rapid quality control and formula development where speed is necessary and a high degree of accuracy is not essential. It is under the jurisdiction of ASTM Committee D10 on Packaging.
Sampling: Normal production or laboratory samples shall be used for this test.
Calibration: A suitable standard check, accurate to ±0.5 psi (±3.4 kPa), should be maintained in the laboratory for quick calibration of the test gage. Gages in constant use should be checked approximately once each week, or immediately after any accidental shock, such as dropping.
✅ Maintenance Tip: For food products, strictly use a separate gage apparatus. The recommended pressurizing gases are limited to those that are not liquefiable at the temperatures and pressures used.
❓ Frequently Asked Questions
🔍 What is the primary application of this practice?
This practice covers rapid pressure determination for pressurized products and is intended for quality control and formula development where speed is required and high accuracy is not essential.
💡 How should the pressure gage be cleaned for nonfood products?
For nonfood products, the gage apparatus should be cleaned between uses by forcing suitable solvents into the gage, then venting it. This should be repeated several times until the gage is free of contamination.
⚡ Which pressurizing gases are recommended for food products?
For food products, Carbon Dioxide (CO₂), Nitrogen (N₂), and Nitrous Oxide (N₂O) are recommended. Compressed air is not recommended because of its oxygen content.
📌 How frequently should the pressure gage be calibrated?
Gages in constant use should be checked approximately once each week, or at any time after the gage has been subjected to accidental shock, such as dropping. A standard check accurate to ±0.5 psi (3.4 kPa) should be used.