Hot
Work/Welding General Safety and Health
Hot work is any work that
involves burning, welding, using fire- or spark-producing tools, or that
produces a source of ignition. Welding and cutting operations are common to
drilling and servicing operations.
Test for
flammable gases in the work area before starting any hot work. Potentially
hazardous areas include, but are not limited to, well heads, fuel tanks, mud tanks, tank batteries, gas separators, oil treaters, or
confined spaces where gases can accumulate.
Hazards
may include and/or be related to the following:
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.
§ Use guards to confine
the heat, sparks, and slag, and to protect the immovable fire hazards.
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.
§ 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.
§ 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.
o Fire watchers shall:
o Have
fire-extinguishing equipment readily available and be trained in its use.
o Be familiar with
facilities for sounding an alarm in the event of a fire.
o 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.
o Maintain the fire
watch at least a half hour after completion of welding or cutting operations to
detect and extinguish possible smouldering fires.
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.
Welding, Cutting and Brazing
All hot work is potentially hazardous and a hazard assessment should
be performed to determine where the hazards exist.
Potential Hazard:
§ Injury and illness
caused by hot work (such as, welding fumes, UV light, sparks, noise, or skin
injury).
Possible Solutions:
§ Inspect the work area
to ensure that all fuel and ignition sources are isolated by shielding,
clearing the area, lockout/tagout, soaking flammable material with water.
§ Wear appropriate
personal protective equipment, such as face shield, leather welder's vest, and
gauntlet gloves. Use cotton or denim clothing.
§ Provide UV shielding
for arc welding where practical.
§ Inspect welding and
cutting equipment before use (arc or gas welding/burning).
§ Leak test gas
torches, gauges, and hoses.
§ Review the hot work
permit if available.
§ Ensure the
availability of adequate fire watch/fire protection equipment.
§ Ensure adequate
ventilation from toxic welding and cutting fumes.
Special Hazard:
§ Accumulation of toxic
gases within a confined space.
§ A hazardous
atmosphere exists in oxygen-deficient (atmospheric concentration of less than
19.5 percent) or oxygen-enriched (atmospheric concentration of more than 23.5
percent).
Possible Solutions:
§ Ventilate toxic metal
fumes mechanically, if entering a confined space, such as inside of a mud
tank, water tank, oil tanks, hoppers, sump, pit or cellar.
§ Use a written permit
system to document authorization to enter, the work to be performed, and the
results of the gas monitoring where there is a potential for toxic, flammable,
or oxygen-deficient atmosphere. Both a hot work and confined entry permit may
be required for welding, cutting or brazing within a confined space.
Cylinder Storage
Potential Hazard:
§ Falling or rolling
injuries from improper gas cylinder storage
Possible Solutions:
§ Ensure cylinders are
properly stored in an upright position and chained in separate racks.
§ Store full and empty
cylinders separately.
Potential Hazard:
§ Valve opening or
break off, exposing workers to toxic fumes and flammable gas, caused by
improper gas cylinder storage
Possible Solutions:
§ Store cylinder
properly.
§ Always remove gauges
and regulators, and install protective valve caps before transporting.
Potential Hazard:
§ Gas cylinders causing
fires or explosions
Possible Solutions:
§ Store cylinders in a
dry, well-ventilated location.
§ Avoid storing
flammable substances in the same area as gas cylinders.
§ Avoid storing
cylinders of oxygen within 20 feet of cylinders containing flammable gases.
§ Store all cylinders
upright and chained in separate racks.
§ Store full and empty
cylinders separately.
Grinding
Potential Hazard:
§ Grinding (that
results in sparks, noise, eye and skin injury from flying metal filings,
grinding wheel pieces, etc.).
§ Having fingers or
hands caught in the grinding wheel, resulting in amputation.
§ Being struck by
portable grinder.
Possible Solutions:
§ Wear appropriate
personal protective equipment, such as face shield. Use cotton or denim
clothing.
§ Inspect grinding
equipment before use.
§ Review the hot work
permit if available.
§ Ensure the
availability of adequate fire watch/fire protection equipment.
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:
o Internal-combustion
engine sparks
o Open flames from any
source
o Smoking
o Welding operations
o Electric power tools
o Two-way radios
o Vehicles with
catalytic converters
o 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 References:
§ OSHA Standards
o 29 CFR 1910.106,
Flammable and combustible liquids
o 29 CFR 1910.252,
Welding, cutting, and brazing - general requirements
o 29 CFR 1910.253,
Oxygen-fuel gas welding and cutting
o 29 CFR 1910.254,
Arc welding and cutting
o 29 CFR 1910.255,
Resistance welding
§ American Petroleum
Institute (API)
o RP 54, Occupational Safety
for Oil and Gas Well Drilling and Servicing Operations, (2007, March).
o Publication 2201, Procedures for
Welding Or Hot Tapping On Equipment Containing Flammables, (2003).
§ National Fire
Protection Association
o 30, Flammable and
Combustible Liquids Code, (2012).
o 51-B, Standard for Fire
Prevention During Welding, Cutting, and Other Hot Work.
§ International
Association of Drilling Contractors (IADC)
o Hot Work Hazard
Recognition
§ ANSI Z49.1-67
Safety in Welding and Cutting, American National Standards Institute.
§ AWS Z49.1-88, Safety in Welding and Cutting and Applied
Processes, American Welding Society.
§ American Petroleum
Institute (API).
o RP 54, Recommended
Practice for Occupational Safety for Oil and Gas Well Drilling and Servicing
Operations, Wireline Service.
o RP 500, 3rd Edition,
Classification of Locations for Electrical Installations at Petroleum
Facilities Classified as Class 1, Division 1 and Division 2.
o 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 Standard.
