Gas Testing standard Req by jakianur


									 1.0        PURPOSE

            The purpose of this standard is to define the minimum requirements for selection,
            maintenance and use of gas testing equipment.

 2.0        SCOPE

            The standard applies to gas testing equipment and activities for confined space
            entry, hot work and maintenance work at SABIC and it’s Affiliates facilities.

 3.0        DEFINITIONS

            3.1    Shall: Signifies mandatory requirements.

            3.2    Should: Signifies recommended/optional requirements.

 4.0        REQUIREMENTS

            SABIC and its Affiliates conducting gas test at their facilities shall develop procedures
            and programs that meets the following requirements:

            SABIC Industrial Security shall be consulted for any clarification to this standard.
            The clarification given by SABIC Industrial Security shall be complied with and
            considered final.

            4.1    Gas testing shall be conducted to ensure that flammable conditions do not
                   exist and that employees will not be exposed to harmful concentrations of
                   toxic substances or oxygen deficient atmospheres.

            4.2    Combustible gas detector instruments shall only be used in atmospheres
                   containing oxygen between 10 – 20.8 % as the instrument will not accurately
                   measure the flammable concentration in oxygen deficient or oxygen rich

            4.3    Non-combustible type gas meters that indicate the percentage of flammable
                   gas or meters designed to measure flammable concentration of gas in oxygen
                   deficient atmospheres shall be used to find out the presence of flammable
                   material in confined spaces/pipings that are purged with nitrogen or other
                   inert material.

            4.4    Chemical reaction tubes or other such instruments shall be used to establish
                   the concentration of toxic or corrosive substances.

July 2001                                 SABIC Safety Standard SF – 133 :                  Page 1 of 7
                                                    Gas Testing
            4.5    Gas testing instruments shall be maintained in good condition because
                   instruments can provide ignition sources for flammable mixtures. Combustible
                   gas detectors with damaged flame arrestor or without flame arrestor shall not
                   be used.

            4.6    Prior to issue of the work permit, the issuing authority shall establish the need
                   for gas testing based on the type of the work and hazards in the area.

                   4.6.1    If hot work is to be performed in an area where flammable mixtures
                            maybe present, GAS TESTING FOR FLAMMABLE VAPORS SHALL BE

                   4.6.2    Tests for toxic or corrosive substances shall be performed when their
                            presence is possible.

                   4.6.3    When entry into a confined space is required, GAS TESTING FOR

                   4.6.4    Tests for toxic or corrosive substances shall also be performed for
                            confined entry when their presence is possible. The test shall be
                            conducted with purge and ventilation equipment stopped.

                   4.6.5    Requirement for periodic gas tests shall be established prior to issue
                            of the work permit.

            4.7    Gas testing shall be conducted to assist operating personnel with various
                   steps of equipment preparation. Such tests assist in purging and washing.

                   These tests are considered preliminary and shall be revalidated prior to issue
                   of a work permit and releasing the equipment to the work crew.

            4.8    Gas meters and chemical reaction tubes shall only be used by personnel
                   trained in proper calibration of the meters and methods of use.

            4.9    Oxygen and explosivity meters shall be tested for proper operability PRIOR
                   TO EACH USE.

            4.10   Before going to the worksite the gas tester shall:

                   4.10.1    Confirm that he understands the specific equipment involved and
                             the gas tests to be performed.

                   4.10.2    Verify that the instrument is functioning properly.

                   4.10.3    Select the correct chemical reaction tube/instrument when tests for
                             toxic substances are specified.

July 2001                                 SABIC Safety Standard SF – 133 :                  Page 2 of 7
                                                    Gas Testing
            4.10.4   Gas testing shall be performed in accordance with the following

            Confined Space

                             a. When entry into a confined space for testing is
                                necessary, the gas tester shall use supplied air
                                respiratory protection and any other protective
                                equipment that may be needed such as impervious
                                boots, chemical resistant suit, gloves, etc. Refer to
                                SABIC Safety Standard SF-132 for further details.

                             b. Ventilation/purging shall be stopped 15 minutes prior to
                                conducting the gas tests, to allow gas concentration to

                             c. Perform gas tests throughout large spaces such as
                                tanks, drums, towers or excavations where it maybe
                                possible for gas to be trapped in dead ends of nozzles,
                                plugged down-comers, structural members, etc.

                             d. Perform gas tests at multiple levels in tall vessels since
                                some gases are heavier than air and tend to settle at
                                the bottom and some which are lighter, will rise to the

                             e. Test for the following in the order specified:

                                  1.       Oxygen
                                  2.       Flammable gases and vapors
                                  3.       Potential toxic air contaminants

            Open Areas

                             a. The    primary     concern  in  open    areas   is
                                flammable/combustible gas. However, gas tests for
                                toxic substances should also be conducted if their
                                presence is suspected.

                             b. Checks should be made around, at and near all
                                openings of the equipment where the work is to be

                             c. Tests should be conducted at sewer openings, open
                                vents, bleeders and at any other possible locations in
                                the area where leaks may be suspected.

July 2001                       SABIC Safety Standard SF – 133 :                  Page 3 of 7
                                          Gas Testing
            4.11   For a gas test to be valid, it should be performed as close as possible to the
                   time that work in the tested area begins. Gas tests shall be repeated:

                   4.11.1   If two hours or more passes between the test and the start of the
                            work. For gas testing of confined spaces, the maximum time is 30

                   4.11.2   When the work is interrupted and then resumes at a later time.

                   4.11.3   In some instances the issuer may specify that gas testing should be
                            continued throughout the course of the work or at specified
                            intervals, i.e., hot work, in an area where conditions could change,
                            or tank cleaning when the work may cause a change in condition
                            through sludge agitation or other by products appearing.

                   4.11.4   If an operational upset occurs or conditions change during the
                            course of the work which could affect the concentration of
                            hazardous or toxic gas at the work site.

            4.12   The name of the person conducting the gas test, test results, date and time
                   of the test shall be written on the work permit.

            4.13   Oxygen testing

                   4.13.1   Oxygen testing shall be conducted prior to entering a confined space
                            or vessel.

                   4.13.2   If the percentage reading is less than 20.8%, action shall be taken
                            to ascertain the nature of the other gas. If it is inert gas then the
                            oxygen content shall be raised by purging with air.

            4.14 Flammability Testing

                   4.14.1   Testing for explosive of flammable mixtures shall be required before
                            all hot work permits are issued for any location where there is a
                            possibility of flammables being present. The test shall be carried out
                            no more than 2 hours prior to the issue of the permit. In the event
                            that the job is stopped for more than 2 hours, a fresh gas test shall
                            be carried out before recommencing work.

                   4.14.2   In locations or conditions where there is a greater likelihood of gas
                            release, Operations Supervisor shall specify repeat gas tests at
                            defined intervals or continuous monitoring in the Work Permit.

                   4.14.3   The concentration of flammable/combustible vapors in the sampled
                            area is measured as the percent of the lower flammable limit in air.

July 2001                               SABIC Safety Standard SF – 133 :                  Page 4 of 7
                                                  Gas Testing
                   4.14.4   If the explosivity meter indicates any % reading, hot work may not
                            be carried out. If further efforts for purging fails to remove all traces
                            of flammable gas, the Operations Supervisor may authorize the hot
                            work to proceed after consultation with Safety, and only if the
                            following conditions are met 1) the source of the flammable material
                            is identified and 2) a determination is made that the concentration
                            cannot exceed 10% of the LEL.

                   4.14.5   The standard explosivity meter gives a % age reading of the lower
                            flammable limit of the gas in air. There may be cases where a
                            nitrogen or inert gas purge has been used and it is necessary to
                            confirm that all the flammable gas has been removed. For these
                            cases, a special testing procedure may be required that will indicate
                            the % of flammable gas, if any, is left in the inert gas.

                   4.14.6   No person shall enter a vessel or confined space that shows a
                            positive reading on the explosivity meter.

            4.15   Toxicity Testing

                   4.15.1   No person shall work in an atmosphere containing toxic gas or vapor
                            in a concentration above the TLV without using appropriate
                            respiratory protection.

                   4.15.2   Specific written instructions, supplied with each container of tubes
                            that contains limitations of the tube performance, possible
                            interference by chemicals and an expiration date for that batch of
                            tubes, shall be followed.

                   4.15.3   Correct Chemical reaction tube/instrument shall be used when tests
                            for toxic substances are specified.

            4.16 Reliability of Test Equipment

                   4.16.1   All users of portable gas test equipment shall be trained in proper
                            use, care, inspection, calibration requirements and limitations of the

                   4.16.2   Only trained personnel shall carry out repairs and maintenance of
                            gas meters.

                   4.16.3   All instruments that are not operating properly (or out of calibration)
                            shall be tagged and sent for necessary repairs.

                   4.16.4   Weekly checks (as a minimum) shall be carried out by the users and
                            a record of these checks shall be kept in logbooks. The weekly
                            inspection shall include the following:

July 2001                                SABIC Safety Standard SF – 133 :                   Page 5 of 7
                                                   Gas Testing
                        Oxygen Meter:

                                                    Inspect squeeze bulb and hoses for
                                                    Calibrate
                                                    Test battery
                                                    Verify response in a known oxygen-deficient

                        Explosivity Meter:

                                                    Inspect squeeze bulb, filters and hoses for
                                                    Calibrate
                                                    Test batteries
                                                    Verify response in a known flammable

                   4.16.5     An external, independent calibration is necessary on a three monthly
                              basis to ensure correct performance of the unit. Preventative
                              maintenance shall also be carried out at this time.

                   4.16.6     This external independent check shall take place on or before the
                              DO NOT USE AFTER/CALIBRATION EXPIRY (Date) that is attached
                              to the instrument.

                   4.16.7     Instruments failing to recharge satisfactorily or calibrate through
                              normal adjustment shall be tagged and dispatched for repairs.

                   4.16.8     All new instruments shall be registered and identified. Any
                              instrument that becomes damaged or inoperative shall be sent for
                              repair or be taken out of service.

                   4.16.9     Instruction Manuals and Response Curve Booklets should be kept
                              with each user department units. Both publications should be used
                              as a first reference in the event of any questions as to the
                              instruments performance.

            4.17   Training

                   4.17.1     Training and qualification program shall be in place for Gas testers.
                              The program shall include classroom and field instruction with
                              testing on the operators’ comprehension of the material presented.
                              The training shall be completed prior to the employee using the
                              equipment without supervision.

July 2001                                 SABIC Safety Standard SF – 133 :                 Page 6 of 7
                                                    Gas Testing
            4.17.2   Training shall include a programmed instruction course on types of
                     gas meters used by the Affiliate its proper use, care, user
                     inspection/calibration, routine replacement of consumable parts
                     (batteries, filters, bulbs, hoses, carrying straps) and limitations. Also,
                     the training shall include the proper use, care, user
                     inspection/calibration, routine replacement of consumable parts
                     (batteries, filters, bulbs, hoses, carrying straps) and limitations.

            4.17.3   Gas meters operators shall pass a written test with a numerical
                     grade 80% or better. In addition to passing the written qualification
                     test, trainees will demonstrate, to the satisfaction of the instructor,
                     their ability to perform pre-operation checks, demonstrate proper
                     use, care, user inspection/calibration, routine replacement of
                     consumable parts (batteries, filters, bulbs, hoses, carrying straps)
                     and give it’s limitations.

            4.17.4   Gas testing Authorization card shall be issued to the qualified gas

            4.17.5   Each gas meter operator shall re-trained and re-qualified every two

            4.17.6   Training shall be documented.

July 2001                         SABIC Safety Standard SF – 133 :                    Page 7 of 7
                                            Gas Testing

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