SOP for Cleaning of Glassware

1.0       OBJECTIVE:

            The purpose of this standard operating procedure is to lay down the procedure for cleaning of laboratory glassware.

2.0       SCOPE:

            This procedure is applicable to all glassware used in the laboratory for analytical                purpose.

3.0       RESPONSIBILITY:

            Laboratory Helper is responsible for doing proper cleaning of glassware as per procedure given and he should aware about handling of glassware.

            Jr. Research Officer/ Research Officer responsible to check cleanliness of glassware.

            QA Officer/QA Manager: Review the records and governing the document.

4.0       Procedure:

4.1       Method - I

4.1.1    Laboratory helper shall collect the glassware to be cleaned.

4.1.2    Empty out the glassware into the drain along with running tap water.

4.1.3    Remove the markings/ stains, if any, with cotton soaked in acetone or methanol.

4.1.4    Rinse the glassware with tap water followed by liquid soap  solution.

4.1.5    Wash the glassware with tap water to remove the detergent and then with purified water.

4.1.6    Finally rinse the glasswares twice with purified water.

4.1.7    Keep the rinsed glassware in the oven for drying at a temperature between 60° to 80° C.

4.1.8        The routine cleaning of all regularly used laboratory glasswares are to be cleaned by the     above-mentioned method.

4.2       Method II:

4.2.1    Laboratory helper shall collect the glasswares to be cleaned.

4.2.2    Empty out the glassware into the drain along with running tap water-potable water.

4.2.3    Remove the markings/ stains, if any, with cotton soaked in acetone or methanol.

4.2.5        Use of hot Nitric acid also effective for cleaning of glasswares.

4.2.5    Hot nitric acid shall be prepared by heating on a hot plate in fume cupboard.

4.2.6    Rinse the glass wares with tap water and pour the nitric acid into glassware, in such a way that, it rinses the inner surface of the glass wares and rinse with tap water.

4.2.7    Alternatively, Chromic acid mixture is also useful in removing organic matter from glass

            without heating.

4.2.8    The mixture prepared by dissolving 200g of  sodium dichromate in about 100ml of water, cooling in an ice-bath & adding slowly to it, with stirring, 1500ml of Sulphuric acid.

4.2.9        Chromic acid mixture is extremely corrosive & hygroscopic, and should be stored in glass-stoppered bottles in  a safe place.

4.2.10    Finally rinse the glasswares twice with purified water.

4.2.11  Keep the rinsed glassware in the oven for drying at a temperature between 60° to 80° C.

4.2.12  Once a week all the laboratory glassware should be cleaned by this method.

5.0       Precautions:

5.1       Use hand gloves and safety goggles while preparing and using hot nitric acid.

5.2       Always prepare hot nitric acid in fume cupboard only.

5.3       Do not allow nitric acid to boil.

6.0              History of Revision:

Revision No.	Effective Date	Revision details	Reason for revision