YY/T 0149-2006Medical instruments of stainless steel - Test methods of corrosion resistance (English PDF)

Foreword

This Standard modifies and adopts ISO 13402:1995, Surgical and dental hand instruments - Determination of resistance against autoclaving, corrosion and thermal exposure. The major differences are as follows.

-- it adds classification in Clause 3;

-- it adds the sodium chloride solution test method in Clause 6;

-- it adds the citric acid solution test method in Clause 7;

-- it improves the content of test evaluation in 5.4, 6.6, 7.6, 8.6, 9.4 and 10.3.

This Standard replaces YY/T 0149-1993, Medical instruments of stainless steel - Test methods of corrosion resistance.

Compared with YY/T 0149-1993, the major changes of this Standard are as follows.

-- it adds the copper sulfate test method in Clause 8;

-- it adds the pressure-steaming test method in Clause 9;

-- it adds the autoclave test method in Clause 10.

1 Scope

This Standard specifies test methods of corrosion resistance of medical instruments and dental hand instruments made of martensitic and austenitic stainless steels.

2 Normative references

The provisions in following documents become the provisions of this Standard through reference in this Standard. For dated references, the subsequent amendments (excluding corrigendum) or revisions do not apply to this Standard, however, parties who reach an agreement based on this Standard are encouraged to study if the latest versions of these documents are applicable. For undated references, the latest edition of the referenced document applies.

GB/T 6682, Water for analytical laboratory use - Specification and test methods (GB/T 6682-1992, eqv ISO 3639:1987)

3 Classification

The test methods of this Standard include the boiling water test method, sodium chloride solution test method, citric acid solution test method, copper sulfate test method, autoclave test method and heating test method.

4 Preparation

The test-specimen shall be degreased and cleaned up. Acetone or other organic solvents can be used to soak or scrub the test-specimen for degreasing treatment; then use water solution containing 0.3% ~ 1% of soap (or washing powder containing no enzyme) and 2% ~ 3% of trisodium phosphate (Na3PO4·12H2O) for soaking at 60°C ~ 70°C; remove the test-specimen and use water to wash; finally, use grade-3 water to rinse.

5 Boiling water test method

Glass beaker or ceramic vessel or suitable corrosion resistant stainless steel vessel.

Examine the corrosion on the surface of the test-specimen; its corrosion degrees can be classified into four grades as follows. […]

6 Sodium chloride solution test method

Sodium chloride (NaCl, of analytical reagent grade).

7 Citric acid solution test method

Immerse the test-specimen in boiling water (4.1) in the beaker for 30 min.

Examine the corrosion on the surface of the test-specimen; its corrosion degrees are as in 6.6.

8 Copper sulfate test method

Scrub the test-specimen using soap and warm water; rinse thoroughly in grade-3 water and dry using isopropyl alcohol or 95% ethyl alcohol.

Visually examine the trace of copper deposition on the test-specimen; the test-specimen shall be free from copper adhesive layer which cannot be removed by rubbing.

9 Pressure-steaming test method

Non-vacuum high pressure sterilizer which is capable of being operated at 134°C ~ 138°C and 0.22 MN·m-2.

Examine the corrosion on the surface of the test-specimen; its corrosion degrees are as in 5.4.

10 Thermal test method

Place the test-specimen in the dry heat oven at (175 ± 5)°C and, after allowing the oven to recover its set temperature, leave it for (30 ± 1) min.

Examine the corrosion on the surface of the test-specimen; its corrosion degree is as in 5.4. […]