For all surface preparation, cleaning, painting and coating or lining purposes, HSE Module Standard 32 (Blasting and Painting) and HSE Module Standard 25 (High Pressure Water Jetting) shall be used as a starting reference to identify all related hazards, assess their risks and put appropriate precautionary measures (and mitigations) into place to effectively manage the intended work.
Other corresponding HSE Modules Standards e.g. Module 02 (Personal Protective Equipment), Module 06 (Scaffolding and Access) and Module 07 (Confined Spaces), including all other known Best Practices and related HSE Safety Alerts shall also be considered for review and appropriate incorporation.
The following requirements, for effective and safe work execution during LIVE operations (SIMOPS) shall be adhered to:
1. Operations in HAC Zones shall be restricted as per Section 5.13.3 below
2. Normal dry abrasive and dry sweep blast cleaning operations shall be treated the same in terms of HSE/risk mitigation requirements
3. The organisation and set-up shall be clearly defined, with each party‟s roles, responsibilities and accountabilities clearly described and communicated
4. There shall be a concise scope of work description and work plan for each specific facility – this includes planning and scheduling (and revisions/updates)
5. There shall be clear communication of the scope of work and planning/scheduling/execution management between offshore and onshore operations/execution personnel
6. The facility shall have been inspected adequately and deemed safe to proceed with the required blast cleaning and painting work. All inspected and identified PARs (in particular INTERNAL corrosion), SARs and defects of concerns shall thus be clearly recorded and communicated to all parties involved
7. All other concurrent works (e.g. welding and cutting) within or near-by the same facility where the blast cleaning and painting work will be executed, must be clearly identified along with interfaces and controls
8. Daily regular and real-time work planning and progress reporting meetings shall be held on-site between the Operations and Executing parties, including the weekly-look-ahead plan/schedule.
5.13.1 High Pressure Water Jetting
HSE Module Standard 25 (High Pressure Water Jetting) shall be used as a starting reference guide to identify all related hazards, assess their risks and put appropriate precautionary measures (and mitigations) into place to effectively manage the intended work at any specific facility. If there are 5B hazards associated with the SIMOPS, the Emergency Escape arrangements must comply to DEM2 PSBR3.
Cleaning by high pressure water jetting, may be required prior to blast cleaning and painting activities, and in some cases before some welding activities. They are normally used to remove drilling muds, grease, oil contaminants and loose rusts from the work surfaces.
Prior to any platform cleaning operation, all unaffected areas are to be physically protected and masked to avoid injury to personnel and damage to sensitive equipment e.g. electrical and instrumentation equipment.
High pressure water jetting may be used with the inclusion of suitable detergents. Any detergents used shall be those approved by the company as “Safe to Use” and bio-degradable.
5.13.2 Blasting
Blast cleaning is normally done either with dry abrasive blast or wet abrasive blast methods.
HSE Module Standard 32 (Blasting and Painting) shall be used as a starting reference guide to identify all related hazards, assess their risks and put appropriate precautionary measures (and mitigations) into place to effectively manage the intended work at any specific facility.
With dry abrasive blast cleaning, the two most notable characteristics are the generation of hot sparks and airborne blast debris. With wet abrasive blast cleaning, the pressurised water entrained abrasives effectively eliminate the generation of any sparks and significantly reduces the airborne blast debris.
Blast cleaning is an aggressive process whereby the violent impacts of the abrasives onto the metal surface not only cleans away the rusts and paint coating but they actually „erode‟ away the metal itself.
Hence, a re-inspection and wall thickness measurements shall be carried out on all identified high-risk items within the work scope on the specific facility to ascertain that it is safe to proceed with actual blast cleaning work execution.
The following requirements, for effective and safe blasting work during LIVE operations (SIMOPS) shall be adhered to:
1. The facility instrument air system shall not be used as an air supply source for the breathing medium of the blaster personnel nor to purge any erected blast cleaning habitats nor to provide the compressed air supply for the blast cleaning and spray painting operations
2. Prior to start of the actual blast cleaning work, all items within the agreed scope of work on the specific facility shall have passed the mandatory pre-inspection integrity verification checks and all identified areas of concerns e.g. PARs and SARs shall have been properly communicated to all involved parties and clearly labelled on that facility. Of particular concern is the ever vigilant focus that is essential to be implemented over corroded small bore piping networks and systems
3. Insulation flanged joints shall be properly masked prior to blast cleaning. In particular the soft non-metallic washers on the stud bolts and the phenolic gaskets are to be properly protected. Upon completion of the blast cleaning and painting application, proper integrity and electrical isolation checks on these flanged joints shall be executed and verified
4. Reinstatement of cathodic protection electrical cables to each pipeline risers shall be done and electrically verified upon completion of the blast cleaning and painting activities. This is to ensure the individual subsea pipeline remains under effective cathodic protection against external corrosion
5. All safeguarding and sensitive equipment e.g. pressure and temperature gauges (not including portable fire extinguishers) shall be properly masked and protected against any damages from the blast cleaning and painting activities
6. The actual number of blast cleaning nozzles/personnel per specific facility shall be individually assessed and shall largely depend on the complexity of the working areas and safe monitoring considerations. This item shall be clearly recorded within the specific PTW assessed and issued for that facility
7. Piping Contact Point and Pipe Support structural areas – surface preparation and cleaning of rusted areas within these specific locations shall only be executed when proper inspections has been done and concluded that it is safe to proceed
8. All rotating equipment and critical components shall be adequately protected and masked to prevent any detrimental ingress of airborne blast cleaning debris
9. Where the blast cleaning has exposed any areas of integrity concerns on the facility, the work shall stop immediately and the Operations Area Authority shall be immediately informed of the exposed concerns
10. Where dry blast cleaning is carried out in the vicinity of accommodation units, air quality checks within the units shall be conducted upon commencement of and periodically during the blast-cleaning program. If air quality falls below acceptable levels (HSE) the accommodation units shall be de-manned or blast cleaning shall cease
11. Static electricity is identified as a potential ignition source. To minimise the build-up of static electricity several precautionary measures are to be strictly implemented:
a. Effective earthing and grounding of the work facilities and the blast cleaning/painting equipment and personnel PPE
b. All the blast cleaning hoses shall be conductive. Conductivity tests and earth grounding between blasting nozzles and the structures shall be carried out at the commencement of the work and at daily shift interval
c. All damaged hoses and equipment or fittings shall be identified, removed from any use on-site and recorded properly before being disposed from workon-site
12. Structural integrity of all the drip pans and supporting structures (whether corroded or not) shall be prior inspected to ensure safe to work on prior to start of actual work
13. Large drip pans and blast cleaning activities, accumulations of waste material may build up creating a weight problem and blockage concerns, the following to be done:
a. Disconnect the drain line system and install proper isolation plugs b. Install an isolation plug in the sump end of the line
c. Divert the drain of the drip pan over the side
d. Continuously flush with water/frequently clean the drip pan to avoid any solid debris build-up and stoppage/plugging problems
e. Drip pans must be cleaned properly prior to reconnection to the sump.
5.13.3 PTW Restrictions for Surface Preparation, Cleaning and Painting
Work permits for surface preparation, cleaning and painting SIMOPS activities shall be restricted as follows:
At night or in low light conditions, no blast cleaning (dry abrasive or wet abrasive or high pressure water jetting) or hand/power tool surface preparation shall be allowed
For Gas Compression areas, dry abrasive blast cleaning shall not be allowed due to the concerns with sparks generation, ignition sources and detrimental ingestion of airborne blast debris into the turbines‟ intake. Therefore:
- Only wet abrasive blast cleaning or high pressure water jet cleaning shall be allowed
- Small scale/spot hand tool surface preparation may be considered if it can be demonstrated to be safe to execute
Piping Contact Point and Pipe Support structural areas – surface preparation and cleaning of rusted areas within these specific locations shall only be executed when proper inspections has been done and concluded that it is safe to proceed
Structural Staircase, Stair Tread and Drip Pans – adequate integrity pre-inspections shall be verified to be safe on such corroded items before allowing any blast cleaning or painting work to proceed on-site
Hand/power tool surface preparation by hammer chipping shall not be allowed
During spray painting application, it must be noted that flammable chemical solvents within the liquid paint are liberated. Thus adequate ventilation, identification and elimination of all ignition sources (including static electricity) are paramount for safe work.
The following additional restrictions shall be applied for work in hazardous areas (HAC Zones):
In Zone 0, no surface preparation or cleaning or painting shall be allowed. All work shall only be done during Shutdown Mode
In Zone 1, dry abrasive blast cleaning shall not be allowed
- Wet abrasive blast cleaning or high pressure water jet cleaning or hand tool surface preparation may be considered if it can be demonstrated to be safe to execute
In Zone 1, any surface preparation/cleaning and painting to be considered and assessed shall be limited to only small spot areas within that specific facility. The painting shall be by brush application only.
Table 18. SUMMARY OF RESTRICTIONS ON BLAST CLEANING IN HACZONES
Activity Zone 0 Zone 1 Zone 2
Dry Abrasive Blast Cleaning No No Yes
Wet Abrasive Blast Cleaning No Yes, provided that:
1. Remaining wall thickness is adequate 2. Adequate PTW controls e.g. continuous gas
detection
3. Rope access or Abseiling method not allowed.
Yes
High Pressure Water Jet Cleaning
No Yes, provided that:
1. Remaining wall thickness is adequate 2. Adequate PTW controls e.g. continuous gas
detection
3. Rope access or Abseiling method not allowed.
Yes
Hand or Power Tool Surface Preparation
No Yes, provided that:
1. Remaining wall thickness is adequate 2. Adequate PTW controls e.g. continuous gas
detection
3. Limited only to small spot areas 4. No hammer chipping
5. Rope access or Abseiling method not allowed.
Yes
Any surface preparation or Blast Cleaning during low light or night conditions
No No No