inspection procedures chlorine cylinder and ton container valves for end users

This Document was prepared by: The Chlorine Institute, Inc., 1300 Wilson Blvd, Arlington, VA 22209, (703) 741-5760. Visit www.chlorineinstitute.org to view a list of other technical documents, pamphlets and safety videos. CI Bookstore: P.O. Box 1020, Sewickley, PA 15143-1020, (800) 662-3916. INSPECTION PROCEDURES – CHLORINE CYLINDER AND TON CONTAINER VALVES – FOR END USERS (Developed by the Chlorine Institute, Inc, Arlington, VA – April 19, 2005) This document was prepared to add an extra level of safety for end users of chlorine cylinders and ton containers. Your chlorine supplier and valve manufacturers have agreed to increase their inspection procedures and an extra check by end users can only enhance safety. Although they are not common, there have been reports of both cylinder and ton container valves being found with cracks in the area by the threads for the packing nut. There are two reported incidents in the U.S. and Canada where an actual leak of chlorine is known to have occurred. Fortunately, most have been discovered before any leaks happened. It appears that the valves will not leak until they are opened since the valve will be sealed at the stem. Both cylinder and ton container valves have been reported with cracks. The valve manufacturer and the Chlorine Institute are working to resolve this problem. Recommendations for the Inspection of Chlorine Cylinder and Ton Container Valves for Cracks by End Users (Valves should be inspected each time before they are opened or reopened-also see item # 3 below for manifold valves) 1. The cracks have been found running longitudinally through the threads by the packing nut. (Note: this is the nut that the valve stem goes through.) The crack may vary from fractions of a millimeter up to 30 millimeters in length. In some instances, a second crack appears perpendicular to this crack about 10 to 30 millimeters below the bottom packing thread. One such crack covered a distance of about 120 degrees around the valve body. (see photos) If any cracks are found, separate and tag the cylinder or ton container and notify your supplier at once. Do not open the valve! 2. If no cracks are found, you can connect your system to the container valve and by following CI recommended procedures, open the valve. A careful check using only the vapors from a 20 degree baume ammonia water (ammonium hydroxide solution) will produce a visible white gas if there is a leak. (See the Chlorine Manual published by the Chlorine Institute or CI Pamphlet # 155, Chlorine Handbook for Water and Waste Water Operators for more details on this test.) If a leak is found, close the valve and contact your chlorine supplier immediately. 3. If you are using ton container valves on manifolds or in chlorine headers, you should inspect these as well every time you change chlorine containers. If a crack is found, close the valve and contact your equipment supplier immediately for instructions.

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Page 1: Inspection Procedures Chlorine Cylinder and Ton Container Valves for End Users

This Document was prepared by: The Chlorine Institute, Inc., 1300 Wilson Blvd, Arlington, VA 22209, (703) 741-5760.

Visit www.chlorineinstitute.org to view a list of other technical documents, pamphlets and safety videos. CI Bookstore: P.O. Box 1020, Sewickley, PA 15143-1020, (800) 662-3916.

INSPECTION PROCEDURES – CHLORINE CYLINDER AND TON CONTAINER VALVES –

FOR END USERS

(Developed by the Chlorine Institute, Inc, Arlington, VA – April 19, 2005)

This document was prepared to add an extra level of safety for end users of chlorine cylinders and ton containers. Your chlorine supplier and valve manufacturers have agreed to increase their inspection procedures and an extra check by end users can only enhance safety. Although they are not common, there have been reports of both cylinder and ton container valves being found with cracks in the area by the threads for the packing nut. There are two reported incidents in the U.S. and Canada where an actual leak of chlorine is known to have occurred. Fortunately, most have been discovered before any leaks happened. It appears that the valves will not leak until they are opened since the valve will be sealed at the stem. Both cylinder and ton container valves have been reported with cracks. The valve manufacturer and the Chlorine Institute are working to resolve this problem.

Recommendations for the Inspection of Chlorine Cylinder and Ton Container Valves for Cracks by End Users

(Valves should be inspected each time before they are opened or reopened-also see item # 3 below for manifold valves)

1. The cracks have been found running longitudinally through the threads by the packing nut. (Note: this is the nut that the valve stem goes through.) The crack may vary from fractions of a millimeter up to 30 millimeters in length. In some instances, a second crack appears perpendicular to this crack about 10 to 30 millimeters below the bottom packing thread. One such crack covered a distance of about 120 degrees around the valve body. (see photos) If any cracks are found, separate and tag the cylinder or ton container and notify your supplier at once. Do not open the valve!

2. If no cracks are found, you can connect your system to the container valve and by

following CI recommended procedures, open the valve. A careful check using only the vapors from a 20 degree baume ammonia water (ammonium hydroxide solution) will produce a visible white gas if there is a leak. (See the Chlorine Manual published by the Chlorine Institute or CI Pamphlet # 155, Chlorine Handbook for Water and Waste Water Operators for more details on this test.) If a leak is found, close the valve and contact your chlorine supplier immediately.

3. If you are using ton container valves on manifolds or in chlorine headers, you

should inspect these as well every time you change chlorine containers. If a crack is found, close the valve and contact your equipment supplier immediately for instructions.