STANDARD OPERATING PROCEDURE Title: Chemical Test for Glass Containers

Purpose:

It is established for glass testing

2. Scope:

This procedure is applicable to glass testing

3. Responsibilities:

1. QC Manager

2. Analyst

4. Procedure:

Type Type of Test Size (ml) ml of 0.02N Acid

I Powdered All 1.0

Glass

II Water Attack 100 or less 0.7

Over 100 0.2

III Powdered Glass All 8.5

Powdered Glass Test:

Rinse about 20 or more containers selected at random, with purified water. Crush it to small glass particles and sieve it through No. 20 and No. 40 sieves. Repeat again this crushing and sieving procedure. Again pass it through No.50 sieve, collect the portion retained on the sieve. Repeat this process till the collection is more than 10 gm.

Wash this specimen with six 30 – 40 ml portions of acetone, swirling each time and carefully decant the acetone. Dry the grains for 20 minutes at 140^oC and cool it in incubator.

Transfer 10gm of dried and cooled specimen to a clean 250 ml conical flask. Add 50ml of highly purified carbon dioxide free water. Prepare a blank with 50 ml of purified water. Cover the flasks with aluminum foil a seal it with autoclave tape. Place the flasks in an autoclave and autoclave for 30 minutes at 121 + 2.0^o C. Cool the flasks at once in running water. Add 5 drops of Methyl Red solution and titrate immediately with 0.02N H₂SO₄ till red color produced.

Record the volume of 0.02N acid used for blank and calculate the volume used for sample.

Water Attack Test:

Rinse thoroughly 3 or more containers, selected at random, twice with highly purified water.

Procedure:

Fill each container to 90 % of its overflow capacity with high purity carbon dioxide free water. Cover all flasks with aluminum foil and seal it with autoclave tape. Autoclave at 121 + 2^oC for 60 minutes. Cool it to room temperature. Emptying the content from 1 or more containers into 100ml graduated cylinder. Place the pooled specimen in a 250 ml conical flask, add 5 drops of Methyl Red solution and titrate it with 0.02N acid.

Complete the titration within 60 minutes after opening the autoclave. Record the volume consumed, corrected for a blank obtained by titrating 100ml of highly purified water treated in the same way.

The volume does not exceed that indicated in the table for the type of glass concerned.