Protecting against industrial flash fires
Stringent standards and certification requirements pertain to clothing worn in flash fire hazard zones. Patricia Gleason guides us through the fine details.
OSHA AND NFPA
Options for industrial flame resistant protective clothing have expanded significantly since the United States’ Occupational Safety and Health Administration (OSHA) issued a memo requiring employers to provide flame resistant clothing in oil and gas well drilling, servicing and production related operations.
These types of industrial operations pose a potential threat of a flash fire, and appropriate protective clothing must be provided to keep employees safe.
While these fires can be brief, their consequences to workers with insufficient protection can be dangerous and result in severe burns or fatalities.
OSHA issued the ‘Enforcement Policy for Flame-Resistant Clothing in Oil and Gas Drilling, Well Servicing, and Production-Related Operations’ to clarify its policy for citing the OSHA general industry standard for personal protective equipment (PPE), 29 CFR 1910.132(a), for the failure to provide and use flame resistant protective clothing (FRPC) in oil and gas well drilling, servicing, and production related operations.
OSHA’s inspection history coupled with scientific evidence, worksite accident and injury data, and the publication of industry consensus standards, indicated a potential for flash fires during certain well drilling, servicing, and production related operations. Drilling contractors, well servicing contractors, and oil and gas companies employ thousands of workers in these operations.
In addition to inherent flash fire hazards, the industry has a history of burn related injuries and fatalities due to flash fires when engineering and administrative controls have failed.
While it is noted that the oil and gas industry has put forth significant efforts to reduce the risk of flash fire incidents, their occurrence is still a possibility, and with that are the resulting burn injuries and fatalities.
It has been documented that the use of FRPC greatly improves worker survival and chances for regaining quality of life after a flash fire. Wearing FRPC can reduce both the extent and severity of burn injuries to the body. OSHA has therefore concluded that employers are required to provide and ensure the use of FRPC during certain operations.
Flash fires
A flash fire is defined as a fire that spreads by means of a flame front rapidly through a diffuse fuel, such as dust, gas, or the vapours of an ignitable liquid, without the production of damaging pressure.
Ignition sources are present in several forms, including, but not limited to: electrical systems, handheld electrical tools, motors, generators, hot work activities and static electricity.
Servicing operations on oil or gas wells that are active or in production involve the accessing and extraction of oil and gas, and also present a potential for flash fires. Servicing operations also include work on inactive wells, such as stimulating, plugging, or capping.
Production related operations presenting potential for flash fires require the use of FRPC. These operations bring the well fluids to the surface, separate, store, gauge, and otherwise prepare the product for delivery. This phase occurs after a well has been drilled, completed, and placed into operation, or after it has been returned to operation following workover or servicing.
Engineering and administrative controls serve to reduce, but do not eliminate, the potential for flash fires occurring during drilling, well servicing, and production related operations.
Flammable liquids or gas could be released and migrate to ignition sources because of an inadequacy or failure in these engineering and administrative controls.
Employers should ensure the use of FRPC in oil and gas drilling, well servicing, or production related operations when there is a potential for flash fire hazards. To address the need for FRPC the National Fire Protection Association (NFPA) in the United States established a Technical Committee, made up of industry experts who developed the first US FRPC performance standards to address industrial flash fire protection fabrics and components in garments. The first standards were approved by the NFPA membership in 2001. Several revisions have occurred since that time.
These standards are now discussed in detail.
NFPA 2112
The NFPA 2112, Standard on Flame-Resistant Garments for Protection of Industrial Personnel Against Flash Fire, 2012 Edition, provides minimum requirements for the design, construction, evaluation and certification of flame resistant garments which are used by industrial personnel with the intent of such garments to provide a degree of protection to the wearer, and not contribute to a burn injury, during a short duration thermal exposure or accidental exposure to a flash fire.The minimum requirements also for flame resistant garments are intended to reduce the severity of potential burn injuries.
Users of the NFPA 2112 standard are advised to refer to NFPA 2113, Standard on Selection, Care, Use, and Maintenance of Flame Resistant Garments for Protection of Industrial Personnel against Flash Fire for conducting the appropriate hazard assessment to identify the in-use area’s minimum protection requirements.
NFPA 2112 establishes certain design requirements for hardware finishes, metal components and slide fastener tape which are used in garments.
For instance, any metal components or closure systems should not come in contact with the wearer’s body, hardware finishes should be free of rough spots, burs or sharp edges, and inherently flame resistant fibres should be used in the construction of slide fasteners.
Labelling and user information requirements specify what information should be placed on the label, and what warnings, information and instructions should be provided with each garment.
Additionally, as issues of proper fit are directly associated with the risk of injury, sizing charts indicating the range of key wearer measurements that are accommodated by each specific size of garment offered must be provided.
NFPA 2112 performance requirements are extensive and include conditioning for certain tests. Conditioning of a material may include certain washing and drying procedures, or dry cleaning. The standard requires fabrics to pass numerous tests such as heat transfer performance according to ASTM F 2700 to measure unsteady state heat transfer properties, and the ASTM F1930, a thermal manikin test involving a jet fuel fire at a specified heat flux, or fire intensity, and exposure time of three seconds. NFPA 2112 sets the performance requirement for ASTM F1930 at a maximum of 50 percent body burn of the total surface area or less to be compliant. Also, each flame resistant garment fabric layer should undergo a flame resistance test in accordance with ASTM D 6413.
There are additional requirements for thread, hardware, emblems and labels. The most recent edition of NFPA 2112 added definition and testing requirements for cold weather insulation materials to ensure that garments incorporating such insulation material are properly tested.
source: http://www.hsimagazine.com/article.php?article_id=968
