Method Statement For LPG Systems Work Installation, Testing & Commissioning

This mechanical method statement provides the details of site wide installation of LPG works for the project. Method statement also outlines the quality procedures for LPG works for the project.

In addition this method statement is made to make the technicians aware of their exposure to the safety risk identified and explain them how to eliminate or to reduce the risk in their specific activity.

Required Tools:

• Pressure Gauge
• Marker pen / chalk
• Ladder, lifelines and accessories
• Hack saw, Pipe cutting machine
• Spanner, Standard Tool kit
• Manual Setting tools
• Hammer Drill
• Welding machine
• Cutting set c/w Cylinders
• Measurement Tape
• Spirit level

PRE WORK CHECK UP:

A check should be made whether drawings are approved by Consultant and authorization is given for the commencement of the piping erection work.

A clear designated area will be allocated for the storage of the pipes, elbows, and other fittings and accessories onsite for the execution of LPG works.

Necessary PPE personnel protective equipment (Hand gloves, safety goggles, dust masks etc.) will be issued to all the operative staffs prior to start of installation works. All personnel need to be safety inducted by main contractor safety officer before commencing work.

Permit to work must be obtained from main contractor before start of any activity onsite and risk assessment made for each activity. Hot work permit should be obtained separately for soldering of copper pipes.

All the material used for the LPG services should be checked for their compliance with the standard and the specifications as mentioned in the Consultant approved material submittals.

All the material delivered to the site should be visually inspected and checked if all complies with the specification. All the pipes are to be stacked in proper racks and the fittings, flanges, clamps and other accessories are to be stored in separate area.

A copy of the approved drawings is to be given to the foreman and technicians onsite prior to the commencement of work.

The site engineer should check the site for the completion of civil works and the portion of the area cleared for installation of sleeves within the concrete.

PVC Containment in Wall / Concrete:

• Building work drawings should be produced according to the required containment for LPG leak detection system.
• All the required containment sleeves to be provided at the site according to the design & dimensions in the drawings.
• Layout for electrical containment to be provided.

Underground Pipe Installations

• After leveling of the ground level, marking has to be made for the excavation for the LPG pipes sleeve. The invert level of excavation is to be given to the surveyor to maintain the required level.
• After excavation the surface is again compacted and 200mm ground to be filled with fine dune sand before laying of the pipes.
• Pipes should be laid according to the invert level as specified in the drawing.
• Ends of pipes shall be brazed with brass adapter coupler to connect the same to isolation valve.
• After laying the LPG pipes, it should be checked for any leakage by dry nitrogen gas. The testing should be at least 1.5 times the working pressure of the pipes for LPG services.
• Pressure/Purging test to be witnessed by Consultant, Calibrated Pressure gauges used for monitoring pressure to be provided with calibration certificate. Pressure testing shall be carried our on partial batches.
• If there is no leak during the pressure test, clearance should be given to the civil contractor.

Above ground pipes Installation Method

• All the pipe routing should be marked and support marking should be done.
• Drilling for the anchor fasteners as per the location of the support have to be carried out.
• All the threaded rods to be installed and part of the pipe clamp to be erected along with the threaded rods.
• All the pipes. Isolating valves and other accessories are to be installed as per the approved drawings.
• Pressure test to the complete pipe system to be carried out to 1.5 times the working pressure. If the pressure testing is successfully completed, then clearance is given to the contractor.
• Pressure test to be witnessed by Consultant, Pressure gauges used for monitoring pressure to be provided with calibration chart.

Installation of Regulator, Solenoid Valve & Other Accessories

• The Gas Regulator, Solenoid Valve & other accessories shall be installed after the completion of all the civil works in gas room.
• The Gas leak sensor & emergency manual shut off switch for Gas detection system shall be installed after completing all tiling work for kitchen area by the civil contractor.
• Final connection of the Gas equipment with auto safety valve shall be done after fixing the gas equipment.
• After fixing the Gas System accessories, check the functioning of installed accessories.
• Seal the joints between fittings and the tiles properly with silicon.
• After completion of the tests, the area can be handed over to the other services after Consultant approval.

Safety Control Measures            

• Prevention of falling materials from height, this would involve toe boards on scaffolding etc.
• All workers to wear appropriate PPE for the task, i.e. goggles, mask, gloves etc. The foreman should provide all the necessary PPE and implement the wearing of it.
• Electrical power tools will be approved, double insulated or grounded to avoid electrical shock.
• Fire extinguishers are to be placed within reaching distance any works that is within risk of a fire.
• Plant and equipment will have third party inspection certificates and be inspected prior to use.
• All personnel entering the site will wear the appropriate PPE.

Emergency Arrangements

• The Health & Safety officer will be responsible for coordinating the emergency procedure. If there is an emergency the Health & Safety officer will be notified immediately.
• The Health & Safety officer will then notify the relevant emergency services if required

• The Health & Safety officer will notify the Safety Advisor of the emergency, if the site nurse is required he will be notified, the Safety Advisor will attend the emergency and take control of the emergency.
• The required notification, investigation and reporting of the incident will be conducted in accordance with the site HSE Plan.

Testing and Commissioning Procedure for LPG System

Testing and Commissioning – Mechanical

• Prior to commencing the commissioning (Installing the Cylinder) of the gas system the following checks shall be ensured.
• The installation and related pressure tests of the under screed copper pipe and above ground copper pipes along with all the fittings should be pressure tested with Nitrogen / Air.

• The pressure testing after fitting all the accessories and complete copper piping installation and brazing completely then we have to do the pressure testing at 1.5 times of working pressure.

• Complete system should be tested at 1.5 times of working pressure with Nitrogen / Air before commissioning with cylinders.

• Confirm that the safety links and accessories related to the fire protection and fire alarm system are tested, approved and put under operation (As per requirement of Client / Consultant).

• Ensure that the entire above are approved by the Consultant

Testing and Commissioning – Electrical

Following checks shall be performed to ensure proper installation and wiring techniques.

Sensors in Kitchen shall be installed at 300 mm from the FFL, as per the standard practice and in such a place where there is easy access of fresh air.

Buzzer and Emergency switch shall be installed near the exit door as per the standard practice.

Solenoid valve to be interlinked with Gas Detector and Emergency Switch.

Power supply (230 V AC) to be given at the point of Gas Detector.

If there is any gas leak inside the kitchen, Gas Detector will give Buzzer and certain level of gas leak the solenoid will cut off and gas flow will be stopped from cylinder room.

Wiring shall be done through proper conduits, and shall be connected through proper connectors and shall be marked with the numbering ferrule etc.

No color coding is required as FP 200, Firetek cable will be used.