Title: Pressure Relieving and Venting Devices Function: Ecology & Safety No.: BC Page: 1 of 7 Reviewed: 6/30/12 Effective: 7/1/12 (Rev.

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1 Preparer: Team Member, North America, Process Safety Center of Expertise No.: BC Page: 1 of 7 Owner: Manager, North America Process Safety Center of Expertise Approver: Sr. Vice President, Ecology & Safety (Signature on File) (Signature on File) (Signature on File) 1. PURPOSE To establish a minimum standard for preventive maintenance and inspection of Pressure Relieving Devices ( Devices ). 2. DEFINITIONS 2.1. As Found The term As Found refers to the condition of the Pressure Relieving Device and its peripherals at the time it is removed from service for inspection or testing Conservation Vent A Pressure Relieving Device installed in the vent line of a tank or vessel, which protects the equipment from over or under pressure and limits evaporative losses. These devices are sometimes installed as a combination unit with a flame arrestor. In these cases, Corporate procedure BC for flame arrestor inspection requirements also applies High Failure Consequence Pressure Relieving Device A Pressure Relieving Device for which a failure to adequately relieve would likely result in: A major fire or explosion, A pressure wave or flying debris that endangers personnel, Release of a cloud of highly toxic material, Significant off-site consequences, or Major environmental damage. These Pressure Relieving Devices are typically those that protect: highly exothermic reaction systems: equipment handling large volumes of flammable gases or liquids above their boiling point; and equipment handling highly toxic, volatile materials Peripherals The inlet and outlet piping and the instruments (including the piping/tubing connections to the process) that are directly associated with the proper functioning of a Pressure Relief Device.

2 No.: BC Page: 2 of 7 2. DEFINITIONS cont d Pressure Relief Valve A spring-loaded or pilot-operated Pressure Relieving Device for emergency venting actuated by the static pressure upstream of the valve Pressure Relieving Device A generic term applying to Relief Valves, Rupture Discs, Rupture Pin Devices, Conservation Vents and Weighted Manway Covers Qualified Person A designated person, who through training and experience, has gained adequate skills for evaluating the adequacy of the design of pressure relief systems and their components Rupture Disc A non-reclosing Pressure Relieving Device for emergency venting consisting of a frangible disc, usually of metal, graphite, or plastic held between special flanges and of such a thickness, diameter, shape and material that it will rupture within a predetermined pressure range Rupture Pin Device A non-reclosing Pressure Relieving Device for emergency venting actuated by the static upstream pressure. This device opens when the compressive strength of a thin, cylindrical metal rod (pin) is exceeded and the pin buckles Safety Critical Instrument As defined by BASF Technical Community N-P-EI-105, an instrument whose failure can lead to a safety incident, release of a hazardous material, etc Weighted Manway Cover A Pressure Relieving Device installed on a tank or vessel manway that provides emergency venting. The device is actuated by the static pressure in the tank or vessel and opens when the pressure force exerted on the cover exceeds the gravity force holding it closed.

3 No.: BC Page: 3 of 7 3. SCOPE This procedure applies to BASF Corporation and all subsidiaries in North America and Mexico. This procedure also applies to (i) BASF Canada Inc., its Canadian subsidiaries, and partnerships in which BASF Canada Inc. and/or its subsidiaries have a majority interest, and (ii) DNA Landmarks. 4. PROCEDURE 4.1. General Requirements Marking Pressure Relieving Devices Installed Pressure Relieving Devices located in the field shall be distinctively marked, preferably using a color code or a legible tag, so that their inclusion in the Pressure Relieving Device inspection and testing program can be readily determined Design Verification Each unit should identify those Pressure Relieving Devices that are High Failure Consequence Pressure Relieving Devices. The design basis for High Failure Consequence Pressure Relieving Devices shall be verified at least every five years to ensure that no process modifications have rendered it inadequate for its application. The accuracy of design calculations for High Failure Consequence Pressure Relieving Devices shall be verified once by a Qualified Person. (See N-G-HE-250 for details). Any new pressure relief system should be evaluated to identify if any new device is a High Failure Consequence Pressure Relieving Device. Before being placed into service, the design of any new, existing, or modified High Failure Consequence Pressure Relieving Device should be verified by a Qualified Person. It is recommended that Pressure Relieving Devices designated as High Failure Consequence be noted in an identifying manner on the P&ID.

4 No.: BC Page: 4 of 7 4. PROCEDURE cont d Preventive Maintenance Programs Each site shall establish written preventive maintenance programs for Pressure Relief Valves, Rupture Discs, Rupture Pin Devices, Conservation Vents and Weighted Manways. The preventive maintenance programs (see BASF Technical Community Guideline N-G-MC-110-Mechanical-equipment Design Relief and Flashback Protection Device Inspection) shall include the following: Program Components Type of Preventive Maintenance Program Conservation Vents, Rupture Discs, Rupture Devices and Pressure Relief Valves Weighted Manways An inventory which identifies each Pressure Relieving Device in use. Documentation For each Pressure Relieving Device: The design basis/calculations for sizing A testing and/or inspection schedule A record keeping system for maintaining testing and inspection results, and if applicable, failure analysis methodology. Technical information such as identification code, material of construction, orifice size, set pressure, operating temperature, installation date, etc. for each Device. Technical information such as identification code, material of construction, size, pressure rating, installation date, etc. for each Device. Tests Means or methods for conducting bench tests. Not Applicable Inspection A written inspection procedure describing the tasks to be completed and the results to be documented with defined responsibilities of the owning, maintenance and engineering departments.. (Table continued on next page)

5 No.: BC Page: 5 of 7 4. PROCEDURE cont d Preventive Maintenance Programs cont d. Program Components Inspection/ Testing Frequency As Found Inspection Pressure Relief Valves Each Pressure Relieving Device shall be periodically inspected and tested based on the: Type of Service Past inspection and testing history for the device and any associated Peripherals. If testing of a Pressure Relieving Device is not feasible or would compromise its integrity, inspection only and/or periodic replacement based on the manufacturer s recommendations or past inspection history may be appropriate. Type of Preventive Maintenance Program Conservation Vents, Rupture Discs, Rupture Devices and Weighted Manways Each Pressure Relieving Device shall periodically be inspected. The inspection frequency shall be determined based on the: Type of Service past inspection history for the device and any associated Peripherals. Each Pressure Relieving Device and its Peripherals shall be visually inspected prior to testing. Any problems observed (e.g. plugging, scale, corrosion, mechanical condition, etc.) shall be documented. (Table Continued on Next Page)

6 No.: BC Page: 6 of 7 4. PROCEDURE cont d Preventive Maintenance Programs cont d. Program Components Inspection/ Testing Details Pressure Relief Valves New Pressure Relieving Devices shall be inspected and tested prior to installation, as required for existing devices. (The manufacturer's test report satisfies the requirements for testing prior to installation.) The Testing Certification must be included with the documentation associated with the Pressure Relieving Device. The vendor s documentation and certification must reference the Pressure Relieving Device by its unique serial number, as opposed to an internal BASF Tag Number. Each installed Pressure Relieving Device shall be periodically removed from service, inspected, tested and, if needed, repaired. A test shall be performed to determine the pressure at which the device relieved in the "As Found" condition. Test results shall be documented. Once the "As Found" inspection and testing is completed, the valve shall be reconditioned (i.e., cleaned and repaired), if necessary, retested and the results documented. Type of Preventive Maintenance Program Conservation Vents, Rupture Discs, Rupture Devices and Weighted Manways Testing is preferred for conservation vents, where practical. If testing is not practical, inspection and reconditioning is adequate Pressure monitoring devices and associated alarms installed to monitor the space between two Pressure Relieving Devices installed in series are Safety Critical Instruments, and shall be inspected and tested at least as frequently as the adjacent Pressure Relieving Devices. After "As Found" inspection and testing, these instruments shall be reconditioned, if necessary, (i.e., cleaned and repaired), retested and results documented Rupture discs shall be stored in such a manner as to not jeopardize the integrity of the disc. Review of Inspection/ Test Results The maintenance and owning departments shall conduct and document a review of all inspection/testing results. Tolerances are to be confirmed against the allowances provided in the applicable codes, such as ASME Section VIII, etc. If required, revisions to the established inspection and testing schedule or to the type of Pressure Relieving Device in use shall be made and documented at this time.

7 No.: BC Page: 7 of 7 5. RESPONSIBILITIES 5.1. Plant/Site Manager The appropriate manager at the site or unit has the primary responsibility for implementing this procedure Manager North America Process Safety Center of Expertise The Corporate Ecology & Safety Manager of the North America Process Safety Center of Expertise has the primary responsibility for initiating, revising, and interpreting this procedure. 6. RELATED DOCUMENTS BASF Technical Community Guideline N-G-MC-110 Mechanical Equipment Design Relief and Flashback Protection Device Inspection BASF Technical Community N-G-HE-250, Guideline Health Safety Environmental Relief Device Design Verification BASF Technical Community N-P-EI-105, Electrical & Instrument Design Instrument PM/PdM BC Flashback Protection Devices/Systems