WELDING/HOT WORKS & HANDLING COMPRESSED GAS CYLINDERS- ADNOC

Refer to ADNOC HSE Standards, HSE-OS-ST07 and HSE-OS-ST14 for details and necessary compliance.  

Minimum Requirements  

Contractors shall implement the requirements of safe work procedures/instructions for welding and hot works as per the ADNOC HSE Standards / ADNOC Group relevant procedures and Permit to Work/WMS requirements.  

Contractors shall ensure that all cutting, welding and allied processes work shall be conducted under the conditions of ADNOC WMS/ Permit to Work Standards.   

Contractors shall ensure control measures, such as using appropriate ventilation and safety devices for the gas supply system, are effective means of controlling hazard at source. PPE used by the personnel shall be a supplement to the control measures.   

Contractors shall consider the use of habitats for Welding/Cutting activities in Hazardous classified areas. Welding habitats are designed to provide a safe and controlled work area where naked flame or hot work activities such as welding, grinding, cutting, can be carried out in classified hazardous areas without the need for a plant/production shutdown. In hazardous areas, based on the risk assessment, pressurized habitats must be used where applicable in line with ADNOC Group requirements.  

Welding habitats can be built into various shapes and around any facility/plant obstacle, to provide the required protection, while constantly supplied with pressurization/breathable air to prevent the ingress of explosive gases or vapours, which are likely to be present. 

Containment of welding habitat enclosures shall be arranged in a way that maintain the prevention of welding slag and welding/grinding sparks from escaping to the possible explosive environment.   

Only pressurized habitats systems that are third party certified to standards IEC60079-13 shall be operated within Zone 1 & 2 hazardous areas.  

Equipment and personnel involved in the hot works shall be certified and approved as per ADNOC Group requirements.  

Contractors shall ensure that a Fire watch is posted where there is a potential for fire or whenever any of the following conditions occur during the activity:   

▪ Proximity of combustible closer than radius of 35 feet (10.7 meters) to the point of activity    

▪ Openings within a radius of 35 feet (10.7 meters) which expose combustible material in adjacent area, 

including concealed spaces in walls, ceilings or floors    

▪ Proximity to hydrocarbon lines and equipment; and   

▪ Combustible material adjacent to the opposite side of metal partitions, walls, ceiling, or roofs, or in contact with pipes, and are likely to be ignited by conduction or radiation.  

Contractors shall ensure that any tank or vessel which has contained flammable products shall be cleaned and ventilated, or purged with an inert gas, and certified as 'gas free' before any welding or cutting work may be performed on it.  

Contractors shall ensure that Fire blankets and curtains are required to be listed, approved, or the equivalent for such use. As a minimum these shall comply with ANSI/FM 4950 [Ref. 3] or equivalent.   

Contractors shall ensure that fire protection, fire extinguishers and trained fire watch are provided at the work site based on the risk assessment, continuously monitors worksite conditions during job progress for changes hat could compromise the safety and ensure that appropriate warning signage is in place at the relevant worksite locations to inform of the danger and/or access restrictions.  

Fire watch shall be well trained in the use of different types of fire extinguishers.  

Fire Watch responsibilities  

▪ Understands the inherent hazards of the work site and cutting, welding and allied processes;   

▪ Ensures safe conditions are maintained during the activities;  

▪ Ensures to have fire-extinguishing equipment readily available and shall have undergone proper training to use it;  

▪ Ensures familiarity with the facilities and procedures for sounding an alarm in the event of a fire; and adheres to the roles and responsibilities.

Note: An additional fire watch shall be required to the areas that are hidden from the view of a single fire watch i.e. other side of partitions, walls, ceilings, etc. The following figure depicts the positioning of fire watch using 35 foot rule.

Contractors shall ensure that all cutting, welding and allied processes conducted in confined space areas shall comply with ADNOC Confined Space Standard .  

All cutting, welding and allied processes conducted in confined space areas shall comply with ADNOC Confined Space Standards. In addition to HSE-OS-ST08, the following safety precautions shall be taken when involved in cutting, welding and allied processes in confined space:

  ▪ When the activity is required over or adjacent to a confined space, personnel shall be briefed on confined space entry permit requirements, hazards associated with the confined space, and shall not enter the confined space without compliance with HSE-OS-ST08;  

▪ Gas cylinders shall not be taken into a confined space, except for air cylinders used for respiratory protection.;  

▪ Fire blankets and curtains are required to be listed, approved, or the equivalent for such use. As a minimum these shall comply with ANSI/FM 4950 [Ref. 3] or equivalent.  

The general requirements of ADNOC Personal Protective Equipment Standards shall be applicable 

Handling, Storage, Use & Disposal of Compressed Gas Cylinders  .   

Minimum Requirements  

Contractors shall ensure proper handling, storage, use and disposal of gas cylinders by implementing necessary precautions while working in camps, work sites etc. 

Contractors shall ensure that Gas cylinders shall be certified and color-coded in accordance with ADNOC Group requirements. Colour code shall be as per the international colour code system such as BS EN 1089- 3.   

Contractors shall pay particular attention to the storage, handling and use of gas cylinders. When in use, gas cylinders shall be secured in trolleys or baskets or secured to a firm support with chains or clamps.  

Contractors shall ensure that the storage of gas bottles must be segregated (toxic, inert, inflammable) and separated as per the distances specified in ADNOC Group requirements. To prevent any fire in case of gas leak, flash back arrestor must be installed in the fuel and oxygen cylinder regulators..  

Contractors shall ensure that Combustible gas cylinders shall be stored away from any possible ignition sources.   

Contractors shall ensure that Cylinder cages shall be tested and certified periodically as per the ADNOC Group requirements.

Contractors shall ensure that compressed gas cylinders shall be handled and used only by properly trained and competent persons. The required training shall be planned and arranged in line with the requirements of this Standards and delivered by ADNOC Group approved training providers. 

Contractors shall ensure that Drivers shall be trained, and their competence demonstrated with regard to the safe transportation of cylinders and this shall include measures to be taken in case of emergency. Similarly, training shall be planned and arranged for delivery by ADNOC Group approved training providers.  

Contractors shall ensure that all compressed gas cylinders received from the requested supplier shall bee checked, documented and inspected.  Cylinders, regulators, fittings and pipe-work shall be regularly inspted and tested.Records of inspection and testing shall be kept and maintained. 

Contractors shall verify supplier documents such as Quality Check (QC) documents (Hydro test/ valid inspection certificates, Safety Device certificate, gas purity Quality Assurance (QA) etc.   

Contractors shall ensure colour code as per the ADNOC HSE Standards and Flashback devices shall be fitted both the regulator and torch end of the oxygen / fuel gas systems.    

 The following requirements shall be taken under consideration for the procurement of compressed gas cylinders and its accessories:  

▪ Any gas cylinder procurement order shall have an approved specification for container as well as Safety Data Sheet (SDS) for the content;  

▪ All gas cylinders shall have a valid test certificate indicating that the cylinder has been tested and has adequate validity time left for inspection and testing; with respect to international standards or their equivalents few of which are mentioned below :  

▪ BS EN 1803 (latest edition) - Transportable gas cylinders - periodic inspection and testing of welded carbon steel gas cylinders (replaced BS 5430 Part-II);  

▪ BS EN 1968 (latest edition) - Transportable gas cylinders - periodic inspection and testing of seamless steel gas cylinders (replaced BS 5430 Part-I);  

▪ BS EN ISO 13769: (latest edition) - Gas cylinders Stamp marking;  

▪ BS EN 1089-3: (latest edition) - Transportable Gas Cylinders - Gas Cylinder identification (excluding LPG) Part 3 Colour coding;  

▪ BS EN ISO 7225: (latest edition) - Gas cylinders - Precautionary labels;  

▪ NFPA-10 - Standards for Portable Fire Extinguishers; and  

▪ ISO 6406-(latest edition) Gas cylinders - Seamless steel gas cylinders – Periodic inspection and testing.

 Standards to be followed for the accessories.

Inspection of Compressed Gas Cylinders:  

All compressed gas cylinders received from the requested supplier shall be checked, documented and inspected. Cylinders, regulators, fittings and pipe-work shall be regularly inspected and tested. Records of inspection and testing shall be kept and maintained.  

The physical condition of the cylinders shall be as follows:  

▪ Supplier shall ensure the required Quality Check (QC) documents (Hydro test/ valid inspection 

certificates, Safety Device certificate, gas purity Quality Assurance (QA) etc.) are provided  

▪ Personnel shall check the physical condition (Visual Inspection) and identification of received 

cylinders including the Hydro test date which shall not be less than a year to expire; and 

 ▪ Cylinders are to be rejected where the absence of labels and colour coding (unknown contents), dents,

cuts or gouges, cracks, laminations, folds and excessive wear. 

 

USE OF COMPRESSED GAS CYLINDERS 

 

Labelling and Colour Coding 

 

(i) Label  

Each individual gas cylinder shall have a label which identifies its contents, it also provides basic safety information on the hazard(s) associated with the product. The label is the primary method of identifying the contents. It is the responsibility of the person filling the gas cylinder to affix a label. The labelling of the compressed gas cylinder shall be in line with BS EN 1089-3, Transportable Gas Cylinders. Gas cylinder identification (excluding LPG), Color coding. 

  (ii) Colour Codes  

Colour coding shall be applied to the shoulder, or curved part, at the top of the cylinder. Colours are chosen based on the properties of content in accordance with the hazard of the gas filled. Some specific gases and gas mixtures are assigned colours relevant to the gas or gas mixture. Instead of the hazard colour, other colours may be assigned based on the components of a gas mixture.  

Colour coding for Specific Single Gases-The following gases shall be identified by specific colours rather than the colour system defined above.   

▪ Flammable gases. For example - Acetylene: Maroon  

▪ Oxidizing gases. For example - Oxygen: White, Nitrous oxide: Blue  

▪ Inert gases. For example - Argon: Dark Green, Nitrogen: Black  

Contractor shall ensure that the storage areas for compressed gas cylinders shall be cool dry, well ventilated and equipped with compartments, or dividing walls of 1.5 meters (5 feet) high which have a fire resistance of 30 minutes. 

Contractor shall ensure that compressed gas cylinders shall not be stored in an enclosed space or the place where the humidity is high, e.g. a vessel hold, unless the storage space is equipped with an oxygen enrichment and deficiency detection system that activates visual and audible alarms both inside and outside the storage area.

Contractor shall ensure that oxygen cylinders and fuel gas cylinders are stored separately. Separate oxygen from fuel gas cylinders by at least 6.1 m (20 ft.), or by a wall at least 1.5 m (5 ft.) high with a minimum half hour fire resistance.   

Contractor shall ensure that Hydro test shall be conducted by a qualified testing facility. For cylinders used in self- contained breathing underwater breathing apparatus in addition to the full retest period of 5 years, an internal visual inspection needs to be performed every 2, 5 years.

Contractor shall ensure the following while transporting compressed Gas Cylinders. 

  

▪ Compressed gas cylinders shall only be transported in properly constructed racks or baskets in which 

the cylinders are vertical and securely fastened by chain or similar means. When not racked, cylinders 

shall be secured in an upright position to prevent toppling.   

▪ Compressed gas cylinders shall only be transported in open vehicles or containers.  

▪ The labelling of the compressed gas cylinder shall be in line with BS EN 1089-3  

▪ Transportable Gas Cylinders. Gas cylinder identification (excluding LPG), Colour coding  

▪ Each cylinder shall be hydrostatically tested at the frequency specified in the Table 7.5.6 below which is in line with European Standards BS EN 1968 (latest edition) .