MEC&F Expert Engineers : OIL & GAS WELL DRILLING RISKS - HOT WORK, FIRE, AND EXPLOSIVE HAZARDS

Monday, November 10, 2014

OIL & GAS WELL DRILLING RISKS - HOT WORK, FIRE, AND EXPLOSIVE HAZARDS



OIL & GAS WELL DRILLING RISKS  - HOT WORK, FIRE, AND EXPLOSIVE HAZARDS










Workers performing hot work such as welding, cutting, brazing, soldering, and grinding are exposed to the risk of fires from ignition of flammable or combustible materials in the space, and from leaks of flammable gas into the space, from hot work equipment. 


Potential Hazard:

Getting burned by fires or explosions during hot work.



Possible Solutions:



The basic precautions for fire prevention are: 


Perform hot work in a safe location, or with fire hazards removed or covered. [29 CFR 1910.252(a)(1)(i)]


Use guards to confine the heat, sparks, and slag, and to protect the immovable fire hazards. [29 CFR 1910.252(a)(1)(ii)








Special Precautions: 


Do not perform hot work where flammable vapors or combustible materials exist. Work and equipment should be relocated outside of the hazardous areas, when possible. [29 CFR 1910.252(a)(1)(ii)]




Make suitable fire-extinguishing equipment immediately available in a state or readiness. Such equipment may consist of pails of water, buckets of sand, hose, or portable extinguishers dependent upon the nature and quantity of the combustible material exposed. [29 CFR 1910.252(a)(2)(ii)]


Assign additional personnel (fire watch) to guard against fire while hot work is being performed. Fire watchers are required whenever welding or cutting is performed in locations where anything greater than a minor fire might develop. [29 CFR 1910.252(a)(2)(iii)(A)]





Fire watchers shall:


Have fire-extinguishing equipment readily available and be trained in its use.

Be familiar with facilities for sounding an alarm in the event of a fire.


Watch for fires in all exposed areas, try to extinguish them only when obviously within the capacity of the equipment available, or otherwise sound the alarm.


Maintain the fire watch at least a half hour after completion of welding or cutting operations to detect and extinguish possible smoldering fires. 29 CFR 1910.252(a)(2)(iii)(B)





Potential Hazard: 


Getting burned by a flash fire or explosion that results from an accumulation of flammable gases, such as Methane or Hydrogen Sulfide, around the wellhead area.



Possible Solutions: 


Monitor the atmosphere with a gas detector. If a flammable or combustible gas exceeds 10 percent of the lower explosive level (LEL), the work must be stopped.


Identify the source of the gas and repair the leakage.






Additional References: 


OSHA Standards 


29 CFR 1910.106, Flammable and combustible liquids

29 CFR 1910.252, Welding, cutting, and brazing - general requirements

29 CFR 1910.253, Oxygen-fuel gas welding and cutting

29 CFR 1910.254, Arc welding and cutting

29 CFR 1910.255, Resistance welding



American Petroleum Institute (API)


Standards. American Petroleum Institute (API).

RP 54, Occupational Safety for Oil and Gas Well Drilling and Servicing Operations, (2007, March).

Publication 2201, Procedures for Welding Or Hot Tapping On Equipment Containing Flammables, (2003).



National Fire Protection Association


30, Flammable and Combustible Liquids Code, (2012).

51-B, Standard for Fire Prevention During Welding, Cutting, and Other Hot Work.




WELL SITE IGNITION SOURCES






There are a number of potential sources of ignition for flammable gases and liquids on the drill site. It is necessary to provide for a general ignition safety program which could pre-empt potential hazards of fire and explosion. 



Potential Hazard: 



Ignition and explosions of flammable gases or vapors from: 


Internal-combustion engine sparks

Open flames from any source

Smoking

Welding operations

Electric power tools

Two-way radios

Vehicles with catalytic converters

Portable generators







Possible Solutions: 


Provide spark arrestors for internal-combustion engines.


Post "NO SMOKING" signs wherever a flammable gas or vapor hazard exists.


Locate "spark producing" equipment or facilities well away from potential hazard areas.


Prohibit vehicles with catalytic converters from the immediate vicinity of the rig.


Prohibit open flames from the vicinity of the rig.






Additional Information: 


American Petroleum Institute (API).


RP 54, Recommended Practice for Occupational Safety for Oil and Gas Well Drilling and Servicing Operations, Wireline Service.


RP 500, 3rd Edition, Classification of Locations for Electrical Installations at Petroleum Facilities Classified as Class 1, Division 1 and Division 2.


RP 505, 2nd Edition, Classification of Locations for Electrical Installations at Petroleum Facilities Classified as Class 1, Zone 0, Zone 1 and Zone 2.



Accident Prevention Reference Guide. International Association of Drilling Contractors (IADC).


29 CFR 1910.106, Flammable and Combustible Liquids. OSHA Standard.

29 CFR 1910 Subpart S, Electrical. OSHA Standards.