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Audit of technical safety and material handling – Petrojarl Varg

During the period 23-25 March 2010, the Petroleum Safety Authority Norway (PSA) performed an audit of material handling and technical safety on the Petrojarl Varg facility. The audit identified one non-conformity relating to the offshore cranes, two non-conformities relating to the emergency shutdown system and six improvement items.


The audit activity is related to the PSA’s main priority, “Technical and operational barriers”, and is part of the PSA’s audit plan for 2010. The purpose of this focus is to highlight the fact that safety-critical barriers must be maintained in a comprehensive and consistent manner, so as to reduce the risk of major accidents as much as possible.

Technical safety comprises important parts of the technical barriers (safety functions), and safeguarding these is important to maintain an acceptable level of risk.

Objective
The objective of the audit activity was to confirm that Talisman Energy Norge AS plans, manages and performs its activities so that the operation and maintenance of Petrojarl Varg conforms to applicable regulations and recognised standards, including maintaining cooperation with Teekay.

Result
The audit of Petrojarl Varg was carried out as planned. The result shows that operations on the facility are managed in a satisfactory manner within the areas covered by this audit. The report contains one non-conformity relating to the offshore cranes, two non-conformities relating to the emergency shutdown system and six improvement items. Function tests were also performed on selected safety systems with satisfactory results.

Non-conformities

Lack of alarm in crane cabins on offshore cranes: Alarm for fire, smoke and gas in the machinery house is not installed in the crane cabin.
Basis:
Alarm for fire, smoke and gas in the machinery house is not installed in the crane cabin on the offshore cranes. As a compensating measure, the alarm is placed in the central control room. We do not find this adequate to meet the requirement in the NS EN 13852-1 standard, which reads “The cabin shall be provided with fire, smoke and gas alarms from detectors in the machinery house and air intakes.” In our assessment, the crane driver should be notified of dangers as soon as possible so he/she can get to safety.

Emergency shutdown system independence: The PSD and ESD systems for controlling the emergency shutdown valves (ESD valves) are not independent.
Basis:
Facilities shall have an emergency shutdown system to inhibit the development of hazardous and accident situations and limit the consequences of accidents, cf. Section 7 of the Facilities Regulations relating to safety functions. The system shall be able to perform its intended functions independent from other systems. Both ESD and PSD operate a common pilot valve for closing ESD valves. If the PSD system fails to close the ESD valve because of common pilot valve failure, the ESD system will not be able to close the valve either.

Securing hydraulic valve position for ESD valves: Valves in the hydraulic system for ESD valves are not secured in the correct position.
Basis:
If the isolation valve is incorrectly operated on common hydraulic return lines from the actuators to the ESD valves, all ESD valves will be inoperable by being locked in the open position. The guidelines to the Facilities Regulations recommend NORSOK S-001 for designing the emergency shutdown system: Manual valves in safety control circuits (e.g. hydraulic return and accumulator supply, means for valve travel time adjustment) shall be secured in correct position.

Improvement items

Systematic overview of safety-critical barriers: Personnel must be informed about which barriers are disabled or weakened.
Basis:
Section 2 of the Management Regulations requires that personnel be informed about which barriers are established and what function they perform. Furthermore, it shall be known which barriers are disabled or weakened. Teekay, which operates Petrojarl Varg, does not currently have a systematic tool available to management/installation manager to survey the status of safety-critical barriers. During the meeting with Talisman on 5 March 2010, we were informed that work was underway to create a suitable system.

Deficient labelling: Labelling of process safety valves and emergency shutdown valves.
Basis:
Random labelling checks of some PSVs and ESDVs uncovered deficient labelling. PSV valves on the second stage separator lacked “tag” labelling from the manufacturer, serial number, technical approval/certification etc. ESDV 004, produced water outlet on first stage valve lacked “tag” labelling.

Line gas detector test: We could not verify that the line gas detection system could perform its intended function at high gas levels.
Basis:
During function testing of line gas detectors, the facility lacked test equipment to test the detection system for high gas levels (5 LELm).

Lack of updates in operating manuals for offshore cranes: The operating manuals for the offshore cranes were not updated.
Basis:
Several copies of the operating manuals for the offshore cranes were stored in the document centre on board. The different copies had different revision dates ranging from 1997 to 2003. In one copy, the cranes’ “tugger winch” was shown as disconnected, while other copies did not show this notation. These winches were originally mounted on the cranes to help control loads. This system has been disconnected. According to the installation procedure – DOC.no. 9913-G-DP-002, rev. 5, item 8.1 relating to weather limitations on Petrojarl Varg, the cranes shall not be used when significant wave height exceeds 4.5 metres. This is not reflected in the load charts found in the operating manuals. We were also informed that some changes in the hydraulic systems had not been updated in the manuals.

Load charts were not updated: The load charts in the crane and load indicator do not reflect requirements in the local procedure relating to weather limitations.
Basis:
According to the installation procedure – DOC.no. 9913-G-DP-002, rev. 5, item 8.1 relating to weather limitations Petrojarl Varg, the cranes shall not be used when significant wave height exceeds 4.5 metres. Neither the load indicator nor the load charts, which are mounted on the wall in the crane cabin, had been updated to meet the requirements in the internal procedure. The load charts and load indicator stated the maximum wave height as 6 metres. According to the crane driver, loads are not lifted from supply ships when wave heights exceed 4 metres.

Operating manual for emergency operation of offshore cranes is in English: A Norwegian operating manual for emergency operation of offshore cranes should be placed in the engine room where the emergency operation is controlled from.
Basis:
The operating manual for emergency operation of offshore cranes is in English. Since the personnel who will carry out the emergency operation are Norwegian, delays or errors in valve operation could easily occur in a stressful situation. The different valves to be operated are spread around the engine room and the system seems somewhat complex.

Other comments

Control room verification: The PSA verified some routines and systems in the central control room. We have some comments on our observations:

Pre-check:
A system called “pre-check” had been established for daily logging of irregularities across three systems: ‘marine systems’, ‘process systems’ and ‘ESD/F&G systems’. A report is compiled daily of equipment reporting more than four error events. If errors are reported from the SAS system, they are corrected immediately.

Log inhibition:
A practical log had been established for connection and disconnection of safety systems. There were relatively few standing alarms.

Meeting with E&I supervisor and maintenance manager: The PSA has the following summary of the discussion with the E&I supervisor and maintenance manager:

Spot checks in the maintenance system:
The PSA requested documentation of performed maintenance on a few safety-critical systems. For safety-critical valves, six valves were defined. These had documented annual leak tests and closure time tests. Results from capacity tests of fire pumps were also presented.

Performance requirements and performed maintenance were also documented for other safety systems.

Undesirable incidents/gas leaks: Lately, the PSA has received several notifications of gas leaks from Petrojarl Varg.

Most of these have involved small/diffuse gas leaks. Despite their size, the PSA expects the operator to take them seriously to avoid escalation. We understand there is a “safety committee” on the Petrojarl Varg which works on accidental hydrocarbon leaks. Additionally, all leaks are investigated extensively.

In many cases, vibrations have caused gas leaks. Pipe systems exposed to vibrations have been analysed and reinforced. This has improved matters, and the work will continue.

Function testing safety systems
Several function tests were performed on safety systems in connection with the audit. Apart from the comment concerning line gas detection, all systems performed satisfactorily.

Offshore cranes' lifting capacity
Section 70 of the Facilities Regulations relating to lifting appliances and lifting gear and appurtenant guidelines refer to NS EN 13852-1 as the standard. Pursuant to Item 5.3.3 Power requirements, the crane’s motor capacity shall be sufficient to maintain full lifting speed and 50 per cent speed during luffing or slewing (whichever requires the most force). Following observation of lifting speed and luffing on crane no. 1, we question if the motor capacity is sufficient to meet the standard’s requirements. Any capacity or speed measurements were not verified during the audit.

Placement of manual emergency release handle
The manual switch/handle for emergency release of lifting wire was placed on the wall of the crane cabin. The causes the crane driver to stretch to reach it and it is thus not optimally placed considering rapid response. The handle’s design will also contribute to a delayed response as compared with a push button. Cf. Section 20 of the Facilities Regulations relating to man-machine interface and information presentation.

Crane access consists of stairs, angled and vertical ladders
The crane access consists of partial stairs and angled and vertical ladders. Pursuant to Section 12 of the Facilities Regulations, relating to handling of materials and transport routes, access and evacuation routes, there shall be a stair or ramp where access to different levels is used daily. The guidelines to the regulations reference, in this case, Norsok Standard S -002N
rev. 4, Chapters 5.1, 5.2.1. and Annex B.

Measurement of offshore crane conformity
TK has performed a measurement of conformity on the offshore cranes in relation to requirements in DNV Technical Report Nr. 07-BGN-4960,rev. 03, Guide for part-implementation of EN 13852-1 on existing offshore cranes on mobile offshore units. The result is listed in the received list of non-conformities Synergi 27674 – derogation application no. 72. The list consists of eight registered non-conformities, whereof two are “red” (non-conformities which must be corrected, according to the guide), three are “yellow” (non-conformities to be evaluated/compensated, according to the guide) and three are “green” (non-conformities normally accepted without compensating measures, according to the guide).

The “red” non-conformities, which are: 1) Crane 2 does not have a camera and 2) The cranes are designed for a maximum “out of service” wind speed of 50 metres/second, are deemed acceptable by the company; based on the fact that Crane 2 is rarely used and that the facility turns with the weather so that the jibs will always be shielded from/with the wind in strong winds.

The company deems the three “yellow” non-conformities to be acceptable:

1) Lack of wind gauge in crane cabin is compensated with wind speed being available from the control room.

2) The crane cabins lack vertical bars (for protecting the cabin’s front window). This is partially compensated by the installation of horizontal bars.

3) Alarm for fire, smoke and gas in the machinery house is not installed in the crane cabin. As a compensating measure, the alarm is placed in the central control room. Our assessment is that this does not adequately fulfil the requirement in the NS EN 13852-1 standard, which reads “The cabin shall be provided with fire, smoke and gas alarms from detectors in the machinery house and air intakes.” In our assessment, the crane driver should be notified of dangers as soon as possible so he/she can get to safety. Se item 5.1.1 Lack of alarm in crane cabin.

We agree with the company’s assessment of the other “red”, “yellow” and “green” non-conformities.