Temporary Connections to Process. Supersedes: 10/31/09 (Rev.02) Preparer: Owner: Approver: EHS Team Member EHS Team Member EHS Manager

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1 Procedure No.: PA Page: 1 of 6 Preparer: Owner: Approver: EHS Team Member EHS Team Member EHS Manager Document Revision Change Table Revision Number Revision Description Revised By Revision Date 01 Changed Header and Footer VB 06/ Changed required attendance requirement to initial and DS 10/09 periodic check. 03 Modified title, steps 1 and 3 and added step 2.7. TD 1/13 Reviewed-No changes BLM 02/18

2 Procedure No.: PA Page: 2 of 6 1. PURPOSE The purpose of this procedure is to: Establish minimum standards when making temporary connections to process equipment and piping. Establish minimum standards for the use of flexible metal hoses at the Port Arthur site to transfer process. 2. DEFINITIONS 2.1. Flexible Metal Hose A flexible metal hose is a corrugated metal hose that can handle aboveatmospheric pressures and is gas tight. It is used for gas and liquid transfers Liquefied Gas 2.3. Braid A liquefied gas is a substance that is a gas at ambient temperatures and atmospheric pressure but is in a liquid state while processing due to pressure or temperature. A flexible wire sheath surrounding a metal hose that prevents the hose from elongation due to internal pressure. Braiding can have single or multiple layers Minimum Bend Radius The smallest radius that a hose can be safely subjected to under use as recommended by the hose manufacturer, measured to the hose centerline Nominal Design Burst Pressure The pressure, based on the minimum annealed ultimate tensile strength of the braid wire and corrugated hose alloy at 70 F and the hose installed straight, at which the hose can be expected to rupture.

3 Procedure No.: PA Page: 3 of 6 2. DEFINITIONS cont d 2.6. Maximum Working Pressure Maximum operating pressure to which the hose should be subjected. It is established at 25% of the Nominal Design Burst Pressure. The hose may be deflected within the specified bend radius range Process Hydrocarbons (liquid or vapor), steam, chemical(s), condensate, etc This is not an all inclusive list, but given as an example Pulsating or Shock Pressures Shock pressures are pressure changes that occur from sudden changes in flow. One cause is fast operation of valves. When there is a possibility of pulsation pressures, the peak pressure shall not exceed 50% (1/2) of the maximum working pressure. When there is a possibility of shock pressures, the peak pressure shall not exceed 17% (1/6) of the maximum working pressure 3. SCOPE This procedure applies to flexible metal hoses used to transfer process at the Port Arthur Site. Any hose used must be compatible with the chemical, temperature and working pressures for the intended service. This procedure does not apply to hoses permanently installed in process piping systems or common utility hoses 4. PROCEDURE 4.1. General Rules Temporary connections between process systems should be avoided if possible. Operations, Maintenance and Engineering shall jointly examine the situation to see if an alternative to using a temporary connection exists For temporary connections, hard piping is preferred. Temporary connections can be hard pipe, a combination of hard pipe and flexible metal hoses, or flexible metal hoses Proper selection of hoses shall be determined by the job and type of service for which it is to be used.

4 Procedure No.: PA Page: 4 of 6 4. PROCEDURE cont d 4.1. General Rules cont d A set of dedicated hoses shall be kept for use with hydrogen, ethylene and propylene. These shall be a T316L or T321 corrugated hose with a SS double braid capable of high maximum working pressures. Some hoses of this type are: Hosemaster Hydraflex (Lake Charles Rubber and Gasket Co.) Flexonics Series 402X (Triplex, Inc.) Flexonics Series RF67-XFC (Triplex, Inc.) The maximum working pressure (MWP) of a metal hose is temperature dependent in that the MWP lessens as the temperature increases. In the following chart, the MWP is for cryogenic temperatures to 70 F. For higher temperatures, consult the manufacturer s data book for a derating factor to apply to the stated MWP. Hose Type Nominal Hose I.D. Min Bend Radius (Intermittent Flexing) Max Working Pressure (psig) Hydraflex Hydraflex 1 ½ Hydraflex X X 1 ½ 19 ½ X RF67-XFC RF67 1 ½ RF Hard piping used for temporary connections will match the Pipe Service Index for the service, including gaskets and bolting. Technical Services shall be consulted to determine if supports are required and/or adequate for the piping Check hoses for residual material and be sure to empty and clean hoses before use if residual materials are found.

5 Procedure No.: PA Page: 5 of 6 4. PROCEDURE cont d 4.1. General Rules cont d Flexible metal hoses used to transfer liquefied gases shall have ANSI raised face weld neck or lap joint flanges and have a legible metal tag listing the maximum allowable working pressure In all instances when a hose is used to transfer chemicals or is connected to any process equipment or piping, a double block and bleed manifold with a backflow prevention device must be utilized to bleed off pressure before disconnecting When configuring drain/bleed valves ensure that they are directed away from personnel Hoses and connection will be checked for leaks at the beginning of transfer and periodically as long as the hose is in use When transferring liquefied gases, do not allow the hose to be blocked in while containing liquefied gas. If a refrigerated liquefied gas is allowed to warm to ambient temperatures, the resulting increase in pressure will likely exceed the pressure limitation of the hose. Valves to the process should be tagged or locked to remain open during the transfer to provide an open path to prevent overpressure Damaged hoses shall not be used. Hoses must be visually inspected before each use and be currently certified in accordance with the site hose testing procedure, detailed in PA Hose Applications Hoses in use should not be placed across normal walkways or aisles, where they may be potential tripping hazards. Where this is not feasible, adequate precautions must be taken to identify the potential trip hazard In all instances where hoses are laid across roads or areas where vehicles may pass, the hose will be protected by placing planking on either side of the hose to bear the weight of the vehicle Prior to disconnecting a hose, the pressure shall be bled off. Block valves and bleed valves and a means of backflow prevention shall be installed prior to a hose being put into service.

6 Temporary Connections in Liquefied Gas Service Procedure No.: PA Page: 6 of 6 Port Arthur, TX. Reviewed: 02/18 Effective: 06/15/08 (Rev.01) Supersedes: 02/05 (New) 4. PROCEDURE cont d 4.1. General Rules cont d Hoses used in chemical service must be emptied, cleared or cleaned after each use to the extent appropriate to the service. If the hose is dedicated for hydrogen, methane, ethylene and propylene service, return it to its proper storage location When a temporary connection is required, a temporary MOC or TSA must be created If a flexible metal hose is used, its maximum working pressure should be equal to or greater than the highest pressure rating of the system to which it is connected. For example, if the hose is connected to Class B1A piping, its maximum working pressure shall be greater than or equal to 740 psig Pulsation or shock pressures, like those encountered with quick opening or closing of valves can inflict severe damage on a hose. If pressure pulsations may be experienced, the working pressure should be derated by 1/2. If shock pressures are present, the working pressure should be derated to 1/ Before the temporary connection is used to transfer process chemicals, the set up shall be inspected by Operations Coordinator or above to insure that the requirements listed in the General Rules section have been followed. 5. RESPONSIBILITIES 5.1. Port Arthur Site Leadership Team Has the ultimate responsibility and accountability for the implementation and auditing of the requirements in this standard. This responsibility includes the purchase, maintenance and inspection of all hoses Environmental, Health, and Safety Manager Has primary responsibility for the initiation, re-issuance, administration, and/or interpretation of this procedure Port Arthur Site Employees and Contractors Have the responsibility to ensure that prior to using a temporary connection to transfer liquefied gases; the user must verify that the pipe, hose, fittings and gaskets are compatible for the job. The hose must be inspected for defects and must have a current annual inspection. 6. RELATED DOCUMENTS NONE.