METHOD STATEMENT FOR COATING OF STORAGE TANKS 1.
Method Statement
1.1.
Scope of work
1.2.
Field of Application
1.3.
Purpose
1.4.
References
1.5.
Plant and General Requirements
1.6.
Manpower & Key Personnel
1.7.
Materials
2.
General Work Methodology
2.1
Preparatory works
2.2
Work Procedure
2.3
Cleaning of Tanks
2.4
Coating application
2.5
Inspection & Testing
2.6
First Anniversary Inspection
3.
Health & Safety Control Measures
3.1.
Safety
3.2.
Risk Assessment
3.3.
Protective & Safety Equipment
4.
Environment Issues
4.1.
General Issues
4.2.
Mitigation Methods
5.
Quality Assurance / Control
6.
Appendices COSHH Assessment Form Risk Assessment
1.
Method Statement
1.1.
Scope of Work This method statement is applicable for Coating of Tanks. TES Painting Specification:-
Painting Standard: AWWA D 102 – 06 Painting System: •
Shell, Roof & Structural Steel – Exterior : ICS-1
•
Shell, Roof & Structural Steel – Interior : ICS-1
•
Bottom – Exterior: Inorganic Zinc Primer, 75 microns.
•
Bottom – Interior : ICS-1
Selection of Painting System: Surface Preparation: SSPC-SP 10/ NACE No.2 – Tank Internal Surfaces. SSPC-SP 10/ NACE No.6 – Tank External Surfaces. Painting Application method: •
Airless Spray
•
Brush for stripe coating of small areas.
Bottom Plate: – Exterior: 1 Coat of Jotun Brand – Resist 78 (Grey) – 75 microns. Shell, Roof & Structural’s:•
External Surfaces – 1 Coat of Jotun Brand – Penguard Primer Red – 50 microns, 1 Coat of Jotun Brand – Jotamastic 87 Aluminium – 200 microns.
•
Internal Surfaces – 2 Coats of Jotun Brand – Tankguard Storage 125 microns each (Light Red, Red) coat as per attached technical data sheet.
1.2.
Field of Application: Area of application shall be the chilled water requirement for the air conditioning.
1.3.
Purpose:
1.3.1
The Purpose of this Method statement is to define construction sequence intend to perform in relation to the Coating of TES Tanks
1.3.2
The Aim of the method statement is to set out the procedures, Precautions to be observed during surface preparation and painting of TES Tanks at site.
1.3.3
This method statement shall be read in conjunction with the applicable project specification, and relevant codes of Coating of Tanks.
1.4.
References
1.4.1
Approved Tank drawing.
1.1.3
Risk assessment
1.1.4
Paints MSDS
1.1.5
Paints data Sheet
1.1.6
ISO 8501-01
1.5.
Plant and General Requirements
1.5.1
Mobile Air Compressor.
1.5.2
Blasting Equipment
1.5.3
Airless Painting Equipment
1.5.4
50 Ton Mobile crane
1.5.5
Certified Lifting Tackles
1.5.6
3 Ton Chain block
1.5.7
Fire extinguisher
1.5.8
Electrical Extension board with Cables
1.5.9
Wooden blocks
1.5.10
Scaffolding with platform to work at heights.
1.5.11
Painting brush.
1.5.12
Grinding Machine (110 Volt)
1.5.13
Wire brush & emery sheets.
1.6.
Manpower & Key Personnel Key personnel in charge of Monitoring and Execution of Blasting and Painting activity:
1.6.1
Project Manager:
1.6.1.1
He shall be responsible for the overall management of the Construction and installation works of this contract.
1.6.1.2
Meet all the contractual requirements pertaining to this activity and Method statement.
1.6.1.3
Be the focal point for all communication and correspondence.
1.6.1.4
Ensure that effective systems to monitor and control the works are implemented, particularly in respect of safety and quality of the works.
1.6.1.5
Directing of construction activities through Project Engineers.
1.6.1.6
Review overall progress of activities pertaining to this method statement and reporting to General Manager of Petron and communication with Client.
1.6.1.7
Take active participation in all QA/QC matters.
1.6.1.8
Coordinate with various agencies to reduce interface problems.
1.6.2
Blasting & Painting Manager He shall be overall responsible for the complete activity including, but not limited to:
1.6.2.1
Work planning and risk assessment at work place.
1.6.2.2
Directing of construction activities through Site supervisors and Foremen.
1.6.2.3
Material Take offs and ordering of bulk materials.
1.6.2.4
Manage manpower, equipments and materials for safe and timely completion of work.
1.6.2.5
Regular monitoring of work ensuring the qualification of personnel, equipment and material.
1.6.2.6
Ensure the quality of work as per the shop drawings / design drawings, Specification, Quality Procedure and coordinate with QA/QC Engineer to advice for the areas to be raised for inspection.
1.6.2.7
Reporting of any non conformance to QA/QC Engineer and to the project manager.
1.6.2.8
Stage inspection and notification to Client for Inspection.
1.6.2.9
Closing of non conformances issued by Client.
1.6.2.10
Ensuring that tool box talks are conducted regularly by supervisors.
1.6.2.11
Ensure that method statement is followed strictly and implemented at site.
1.6.3
Painting Supervisor
1.6.3.1
Conducting Tool Box talks to explain the work procedure and maintain safety guidelines.
1.6.3.2
Manage the Paint storage container and Paint material stored.
1.6.3.3
Plan and allocate blasters and painters, paint materials and tools.
1.6.3.4
Measure, Monitor and Maintain Relative Humidity Records.
1.6.3.5
Supervise the blasting and painting activities
1.6.3.6
Measure and Record WFT and DFT.
1.6.3.7
Ensure correct procedures, materials and documentation are applied in coordination with QA/QC Engineer.
1.6.4
QA/QC Engineer
1.6.4.1
QA/QC Engineer shall be overall responsible for QA/QC activities.
1.6.4.2
He shall be responsible for the execution of correct Blasting and Coating techniques and control with respect to this Method Statement and reference documents.
1.6.4.3
Witnessing all Checks / tests.
1.6.4.4
Maintaining records of calibration, inspection and testing equipment.
1.6.4.5
Documentation of test records and stage inspection.
1.6.4.6
Reporting and monitoring of non-conformance status.
1.6.4.7
Close out NCR’s if any.
1.6.5
Scaffolding Foreman & Scaffolding erectors Scaffolding Foreman will be trained and hold Scaffolding Certificate. He will be responsible for inspection, verification and Tagging all the scaffolding materials and supervise erection of scaffold. He shall conduct TBT for all scaffold erectors and monitor their erection activities.
1.6.6
Blaster Responsible for performing blasting operation; connect and check the integrity of connections of blasting hoses, nozzles; abrasives storage and handling; cleaning and clearing of spent abrasives. Report to Blasting and Painting Manager.
1.6.7
Painter Responsible for performing paint application as per paint manufacturer’s recommendations, Technical Data Sheets and this method statement. Maintain the Airless Spray machine and Spray Gun by thoroughly cleaning
before and after painting operation. Report to Blasting and Painting Manager.
1.6.8
Stand by man for Blaster / Painter Responsible for acting on the signals issued by Blaster/ Painter and operate the Air Compressor and Blasting/ Painting Equipment. He shall maintain visible contact with Blaster/ Painter at all times and shall not leave the site during operation.
1.7.
MATERIALS
1.7.1
Material Receipt
1.7.1.1
The materials received at site stores / Site shall be checked for manufacture’s details, as per delivery note and to ensure delivery is correct.
1.7.1.2
Verification of Quantity as per Delivery Notes, the Packing list and Test certificates shall be done by Stores personnel.
1.7.1.3
Details of the material receipt will be conveyed to Project Engineer and Quality Engineer.
1.7.1.4
Related Material information’s will be conveyed to Client and will be integrated with requirements and procedures of Client.
1.7.1.5
Respective Information’s will be conveyed to Project Engineer for arrangement of unloading, if necessary and issue of material.
1.7.1.6
Responsibility for this lies with Overall In charge of stores at site.
1.7.1.7
Site incoming material control procedure SE-BEN-01AP-PRO-00011 shall be followed.
1.7.2
Material Handling
1.7.2.1
Use hand gloves for shifting / unloading / loading / handling etc.
1.7.2.2
Offloading will be done with appropriate Handling Equipments of required capacity using a nylon sling, Belts.
1.7.3
Material Storage
1.7.3.1
Paints shall be stored in well ventilated air-conditioned Storage Container at temperature recommended in the manufacturer’s product data sheets with proper identification and fire extinguishers.
1.7.3.2
MSDS (as per Directive 1999/45/EC) shall be prominently displayed at the Storage Container.
1.7.3.3
In case of Spill, Contain and collect spillage with an electrically protected vacuum cleaner or by wet-brushing and place in container for disposal . Do not allow to enter drains or watercourses.
2.
General Work Methodology
2.1.
Preparatory Works
2.1.1
Place the blasting compressors (2 nos). Place one mobile wheel mounted compressor on firm base outside the tank. Place one compressor inside the tank on the bottom plate using 50T Crane (Roof Plate is not erected).
2.1.2.
Connect the blasting hoses and check the moisture separator and adjust the drain of moisture separator so that a constant clean and dry air is discharged at required pressure.
2.1.3.
Cover all nozzle faces with wooden blanks to protect from damage due to blasting.
2.1.4.
All personnel working shall be wearing PPE. Blaster shall wear brothering apparatus.
2.1.5.
Garnet shall be used as abrasive for cleaning (GMA Garnet – Australia).
2.1.6.
Abrasives for blasting shall be preserved only in its original bag packing and placed on wooden planks / pallets.
2.1.7.
The paints shall be stored in 20 ft. container fitted with air conditioner and fire extinguisher (CO2, Dry Powder, Water spray). MSDS (as per directive 1999/45/EC) for the paints shall be pasted on the storage container door.
2.1.8.
In Case of spill: Contain spillage with non-combustible, absorbent material like sand, earth, vermiculite and place in separate container for disposal. Do not allow to enter drains or water courses.
2.1.9.
Risk phrases : R 20 /22 –
Harmful by inhalation and if swallowed
R 34
-
Causes burns
R43
-
May cause sensitization by skin contact
R52/53 -
Harmful to aquatic organisms, may cause long-term adverse effects in the aquatic environment.
2.1.10.
Safety phrases : S23 – Do not breathe, vapor /spray S26 – In case of contact with eyes, rinse immediately with plenty of water and seek medical advice. S36/37/39 - Wear suitable protective clothing, gloves and eye / face protection. S45 – In case of accident or unwell, seek medical advice immediately (show label where possible) S51 – Use only in well ventilated areas.
2.1.11.
First aid measures : General :
Inhalation :
In all cases of doubt, or when symptoms persist, seek medical attention. Never give anything by mouth to an unconscious person Remove to fresh air. Keep person warm and at rest. If not breathing, if breathing is irregular or if respiratory arrest occurs, provide artificial respiration or oxygen by trained personnel. Give nothing by mouth. If unconscious, place in recovery position and seek medical advice.
Skin contact:
Eye contact:
Ingestion :
2.1.12.
Remove contaminated clothing and shoes. Wash skin thoroughly with soap and water or use recognized skin cleanser. Do not use solvents or thinners Check for and remove any contact lenses. Immediately flush eyes with running water for at least 15 minutes, keeping eyelids open. If swallowed, seek medical advice immediately and show the container or label. Keep person warm and at rest. Do not induce vomiting.
Fix heavy duty exhaust fans on shell man holes S05 (24”), S06/36”), S08 (16”) and S10 (16”) for ventilation during blasting and painting.
2.1.13.
Lay scaffolding all around the tank shell both inside and outside at 750mm away from the shell. Lay wooden working platforms at every 2 mtr level and ladders for access to blaster / painter all around the shell.
2.1.14.
The entire outside of the tank shell scaffolding will be laid with green knitted cloth to contain and prevent blasting dust / paint vapor to spread around the worker.
2.1.15.
The top of the shell (Roof not fitted during tank shell blasting and painting) will also be laid with green knitted cloth to prevent dust spreading to the atmosphere.
2.2. 2.2.1
Work Procedure After completion of erection of tank bottom plate, shells and nozzles, blasting of tank internal and external by 2 independent groups shall be carried out.
2.2.2
Thorough cleaning of tank internal to remove construction debris to the performed before start of work. All weld slag, weld spatters and tack welds shall be removed by chipping / wire brushing and or grinding.
2.2.3
Internal surfaces shall be blast cleaned in compliance with SSPC-SP10/NACE No.2 and external surfaces in compliance with SSPC-SP10/NACE No.6(as per contract specification) or according to Paint Manufacturer’s recommendations.
2.2.4
The blasting and painting shall be performed in stages as detailed below : •
One group of blaster & painter can cover 70 to 100 sq.mtr surface area in one day shift.
•
Blaster and Painter will be assisted by stand by Man for controlling the air compressor regulator for open/modulation/shut off.
•
Blasted surface shall be painted within a maximum period of 6 hours. In case the waiting period exceeds, the surface shall be examined. Sweep blasting to be performed to remove any deposits surfaces.
•
Blasting shall not be performed where the relative humidity is more than 85%
• 2.2.5
RH shall be monitored and recorded at regular intervals.
The roof with structures shall be blast cleaned and painted on ground before erection. The welding area between roof & shell shall not be painted and masked with masking tape. This area shall be blast cleaned and painted after erection and welding.
2.2.6
There shall be at least 6” of overlap on either side of weld area. This overlap area will be sweep blasted to crate rough surface (not complete blasting) for adhesion of paint.
2.2.7
The abrasives after blasting will be collected manually from the work area and packed in the same bag as supplied and disposed off through Trucks from Muscat Municipality according to local regulations.
2.3
Cleaning of Tanks
2.3.1
Remove all visible oil, grease, dirt, dust and other contaminants from inside and outside the tank by high pressure jet washer.
2.3.2
Surface imperfections such as sharp fins, sharp edges, weld spatter, or burning slag should be removed by grinding / chipping / wire brushing.
2.3.3
Perform Blasting to SSPC-SP-10/NACE No.2 by using Dry abrasive blasting using compressed air, blast nozzles and abrasives.
2.3.4
Blasting shall not be performed if one or more of the following conditions exist:
2.3.5
Relative humidity is greater than 85%
2.3.6
There is a risk of any of the above condition during the blast cleaning
2.3.7
Spent abrasives, dust and loose residues shall be removed from prepared surfaces and thoroughly cleaned by brush or by compressed air.
2.3.8
Visually Inspect the entire surface to comply with the degree of cleaning specified i.e. Near White Metal Blast Cleaned Surface according to SSPCSP10/NACE No.2.
2.4
Coating Application
2.4.1
The Coating shall not be applied when the metal surface temperature is less than 3˚C above the dew point.
2.4.2
The minimum temperature and temperature of paint should be above 10˚C/50˚F.
2.4.3
Surface should be clean and dry.
2.4.4
Relative humidity of the air max 85%.
2.4.5
All weld joints and corners shall be given a stripe coat by brush prior to spray coating applications.
2.4.6
Recoating intervals shall be as given in the manufacturer’s data sheet.
2.4.7
Airless spray pumps shall be use by paint manufacturer’s recommended fluid pressure at spray tip between 1400 p.si. to 2100p.s.i. for coating application.
2.4.8
All equipments for coating application shall be thoroughly cleaned before and after use with the manufacturer’s recommended tool cleaner/thinner.
2.4.9
Surface Preparation & Painting shall be carried out after completion of all applicable NDT.
2.4.10
All 2 component Paints shall be mixed thoroughly with a portable Electrical Stirrer.
2.4.11
The mixing ratio for the paints used on this tank are listed below:-
Resist 78:Mixing ratio (volume) 9:2,6 Mixing Comp. A is a liquid and Comp. B is dry zinc dust. Consists of 9 litres Comp. A and 18.5 kg/2,6L Jotun Zinc 100, Comp B or 18,5 kg/2,6 litres Jotun Zinc 100 ASTM D520 Type II, Comp B. Pour the zinc dust slowly into the liquid during mechanical mixing. The Comp. A must be well shaken before use. Stir until lump free and pass through a 60 mesh sieve. Pot life (23°C) 8 hours.(Reduced at higher temp.) Pressure at nozzle 10 MPa (100 kp/cm², 1400 psi) Nozzle tip 0.46-0.58 mm (0.018-0.023") Penguard Primer:Mixing ratio (volume) 4:1 Mixing 4 parts Penguard Primer Comp. A (base) to be mixed thoroughly with 1 part Penguard, Comp. B (curing agent). Induction time 30 minutes Pot life (23°C) 8 hours. (Reduced at higher temp.) Pressure at nozzle 15 MPa (150 kp/cm², 2100 psi) Nozzle tip 0.46 - 0.58 mm (0.018-0.023") Jotamastic 87 Aluminium:Mixing ratio (volume) Std Comp. B: 5,5:1 Mixing 5.5 parts Comp. A ( base) to be mixed thoroughly with 1 part Jotamastic 87, Std Comp. B (curing agent) Induction time 10 minutes. Pot life (23°C) Std Comp. B: 1½ hours Pressure at nozzle 15 MPa (150 kp/cm², 2100 psi). Nozzle tip 0.53 - 0.79 mm (0.021-0.031")
Tankguard Storage:-
Mixing ratio (volume) 6,5:1 Mixing 6,5 parts Comp. A (base) to be mixed thoroughly with 1 part Comp. B (curing agent) Induction time 20 minutes. Pot life (23°C) 4 hours (Reduced at higher temp.) Pressure at nozzle 15 MPa (150 kp/cm², 2100 psi) Nozzle tip 0.46-0.69 mm (0.018-0.027") 2.5
Inspection and Testing
2.5.1
The Painting System shall be inspected as per related specification & SSPC-PA2.
2.5.2
The dry film thickness shall be within the minimum and maximum limits allowed
2.5.3
Generally free of application related defects such as sags, drips, dry spray or foreign matter in the approved coating system.
2.5.4
Areas with blisters, cracks, pores or below the minimum dry film thickness shall be repaired.
2.5.5
Uniform in appearance.
2.5.6
All coated Tank shall be holiday tested according to AWWA D102- 06,Sec. A.8.3 : The Standard does not require holiday testing for inside nonimmersed surfaces above the TCL (Top Capacity Level) and other nonimmersion surfaces. Low Voltage Wet Sponge Tester with Voltages ranging from 5 t0 90 V DC shall be used and Holiday Testing performed according to NACE Standard RP0188-99;
Item
No.
21038
“Standard
Recommended
Practice
Discontinuity (Holiday) Testing of New Protective Coatings on Conductive Substrates”.
2.6
First Anniversary Inspection:The Interior and Exterior surfaces shall be inspected within one year after coating work has been completed as per AWWA D102-06.Remedial Work. Any location where layers of coating have peeled off, bubbled, or cracked, and any location where rusting is evident, shall be considered to be a failure of the coating system. Rust stains emanating from inaccessible areas, such as un-welded roof plate lap joints and where roof plate lap cross supporting members, are acceptable as the rust stains do not affect the integrity of the coating surface. Repairs shall be made at points where failures are observed by
removing the deteriorated coating, cleaning
the surface, and recoating with the same coating system. The manufacturer’s cure time requirements for coating repair shall be observed. If the area of failures exceeds 25 percent of the area of
a
portion of the tank surface, then for that portion, the entire coating system shall be removed and that section recoated. For purposes of determining the need for complete recoating, the following separate area, and any individual accessories not specifically identified, shall each be considered differently:
3 3.1
3.1.1
Health and Safety Control Measures Safety
Safety risk assessment shall be performed for every job or task, which has the potential for harm.
3.1.2
Ensure Personal Protective Equipment (PPE) is available with all the workers involved in the installation / erection work.
3.1.3
All required equipment and tools should be checked before start of work for suitability and integrity.
3.1.4
Necessary permit to work to be obtained as per the site requirement.
3.2
Risk Assessment In addition to their safety induction received at their arrival on site, all workers will have a toolbox meeting and briefed about the risks of their specific work task, prior to start of works. A relevant risk assessment is attached.
3.3 3.3.1
Protective & Safety Equipment Safety helmet, safety boots, Dust masks, safety glass , hand gloves and Breathing Apparatus for Blasters.
3.3.2
3.4
Fire Extinguishers
Environment Issues In general Environmental issues arising from the construction activities covered in the scope of this Method Statement are mainly:
3.5
General issues
3.5.1
Dust and paint spray COSHH Essentials: * the process and task(s) being carried out; * the chemical(s) used and whether a solid or liquid; * the Risk phrases that appear on the safety data sheet; * the dustiness of the chemical if a solid or the volatility if a liquid; * how often the task is carried out and how long it takes; * how much of the chemical is used. COSHH Essentials then worked out the control measures needed Skin or eye contact
COSHH essentials: Harm via skin or eye contact Control approach S Supplementary advice Direct contact – handling, immersion; ■ splashes and dust or spray settling on the skin; and ■ touching contaminated surfaces, including work clothing. Skin contact is almost inevitable. Once the hands are contaminated, contamination spreads to other parts of the skin or into the mouth by touching or scratching. Exposure control • Reduce the chance of contact with skin or eyes: • segregate clean and dirty areas to reduce the spread of contamination; • provide smooth, impervious, easily cleaned surfaces; • launder work clothing regularly; • provide clean washrooms. • tell workers about the risk and about good personal hygiene; • check skin for dryness or soreness regularly; • clean the workroom regularly; • provide eye protection where there are splash risks; and • plan how to deal with spillages swiftly and safely. • Workers should wash their hands before and after eating, drinking, • smoking, using the lavatory or applying cosmetics. Ex
Types of PPE • chemical protective gloves; • coveralls; • protective footwear; • face or eye shields; • respiratory protective equipment (RPE).
3.6
Mitigation Measures
3.6.1
The Blasters and Painters will receive tool box talk in order to avoid excessive exposure to Dust and Fumes
3.6.2
Appropriate Dust / Fume Masks; Face shield shall be used.
3.6.3
General House keeping rules for all operatives shall be observed.
3.6.4
Noise level shall be monitored to assess the impact to operatives involved into this construction activity directly and shall be provided earplugs if necessary.
3.6.5
Proper care shall be taken to ensure that paint spill is avoided.
4
Quality Assurance / Control
4.1
Ensure availability of latest “Approved for Construction” drawings and specifications.
4.2
Ensure Check and hold points are followed as per ITP.
4.3
Works execution inspection and Tests shall be monitored, witnessed and recorded according to the inspection and Test Plan
5
Appendices
5.1
COSHH Assessment
5.2
Risk Assessment
