Transcript Painting_1.ppt

Dipping And
Coating
Operations
Summary
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Rule developed to accomplish
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Rewrite former standards in plain language
Consolidate former requirements
Increase compliance options
Coverage and Definitions -1910.123
Does This Rule Apply to Me?
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When a dip tank contains a liquid other than water
When you use a liquid or vapors to:
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Clean or coat
Alter the surface
Change the characteristic
Draining or drying an object,dipped or coated
What Operations Are Covered?
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Paint dipping
Electroplating
Pickling
Quenching
Tanning
Degreasing
Operations Covered (Continued)
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Stripping
Cleaning
Roll coating
Flow coating
Curtain coating
What Operations Are Not Covered?
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An operation that only uses a molten material
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Alloy
Salt
How Are Terms Defined?
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Adjacent area
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Approved
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Any area within 20 feet of a vapor area that is not separated
by tight partitions
Designated equipment - listed/approved by a nationally
recognized testing laboratory
Autoignition temperature
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The minimum temperature required to cause self-sustained
combustion, independent of any other source of heat
Terms Defined (Continued)
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Combustible liquid
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A liquid with a flash point of 100 deg.F or >
Dip tank
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A container holding a liquid other than water and used for
dipping or coating
– An object may be immersed (or partially immersed) or it may be
suspended in a vapor area
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Flammable liquid
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A liquid with a flashpoint < 100 deg.F
Terms Defined (Continued)
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Flashpoint
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The minimum temperature where a liquid gives off a vapor
in sufficient concentration to ignite
Lower flammable limit (LFL)
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The lowest concentration of a material that will propagate a
flame
– Expressed as a % by volume of the material in air (or other oxidant)
Terms Defined (Continued)
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Vapor area
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Any tank, including drain boards, drying or conveying
equipment, and any surrounding area where the vapor
concentration > 25% of the LFL
You
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The employer, as defined by the occupational safety and
health act of 1970
General Requirements -1910.124
What Construction Requirements Apply to
Dip Tanks?
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Any container that must be strong enough to
withstand any expected load
What Ventilation Requirements Apply to
Vapor Areas?
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Keep airborne concentration < 25% of its LFL
Meet levels specified Subpart Z
Use of tank covers or floating materials
When You Use Mechanical Ventilation?
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Must conform with standards incorporated by
reference:
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ANSI
NFPA
ACGIH
Draw the flow of air into a hood or exhaust duct
Mechanical Ventilation (Continued)
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Tanks must have an independent exhaust system
unless the combination of substances being
removed will not cause a:
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Fire
Explosion
Chemical reaction
What Requirements Must I Follow to
Recirculate Exhaust Air?
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Can not recirculate exhaust air when substance
poses a health hazard to employees
> 25% the LFL
Recirculate Exhaust Air (Continued)
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Exhausted air recirculated using flammable or
combustible liquids is:
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Free of any solid particulate
Monitored by approved equipment
Sounds an alarm, automatically shuts down when
the vapor concentration > 25% the LFL
What Must I Do When I Use an Exhaust
Hood?
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Provide area with a volume of outside air that is at
least 90 % of the volume of the exhaust air
Outside air supply does not damage exhaust hoods
What Requirements Must I Follow When an
Employee Enters a Dip Tank?
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Meet the entry requirements for permit-required
confined spaces
What First-aid Procedures Must My
Employees Know?
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The first-aid procedures that are appropriate for the
operation
What Hygiene Facilities Must I Provide?
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Lockers or other storage space to prevent
contamination of employee's street clothes
Emergency shower and eye-wash station close to
the operation
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Can use water hose at least 4’ and at least 3/4” thick, a
quick-opening valve, and a pressure of 25 lbs. psi or <
At least one basin with a hot-water faucet for every 10
employees
What Treatment and First Aid Must I
Provide?
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A physician's approval before an employee with a sore,
burn, or other skin lesion that requires medical treatment
works in a vapor area
Treatment by a properly designated person of any small
skin abrasion, cut, rash, or open sore
Appropriate first-aid supplies located near the operation
Employees who work with chromic acid, periodic
examinations of exposed body parts, especially their
nostrils
What Must I Do Before an Employee
Cleans a Dip Tank?
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Drain the tank, open the cleanout doors
Ventilate and clear any pockets where hazardous
vapors may have accumulated
What Must I Do to Inspect and Maintain My
Dipping or Coating Operation?
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Inspect hoods and ductwork of ventilation system
for corrosion or damage:
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At least quarterly during operation
Prior to operation after a prolonged shutdown
Ensure that the airflow is adequate:
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At least quarterly during operation
Prior to operation after a prolonged shutdown
Inspect and Maintain (Continued)
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Periodically inspect all equipment
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Covers
Drains
Overflow piping
Electrical
Fire-extinguishing systems
Promptly correct any deficiencies
Inspect and Maintain (Continued)
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Provide mechanical ventilation or respirators to
protect employees from exposure to toxic
substances during
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Welding
Burning
Open-flame work
Clean solvents and vapors before permitting
welding, burning, or open-flames
Additional Requirements for Flammable
or Combustible Liquids - 1910.125
Flammable or Combustible Liquids
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Must comply 1910.123, 124, 125, and126
Must comply if:
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Flashpoint of flammable or combustible liquid is 200 deg. F
or >
Liquid is heated as part of the operation
Heated object is placed in the liquid
What Type of Construction Material Must Be
Used in Making My Dip Tank?
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Noncombustible material
When Must I Provide Overflow Piping?
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Properly trapped overflow piping that discharges to
a safe location for:
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A capacity > 150 gallons
A liquid surface area > 10 feet
Overflow Piping (Continued)
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Overflow piping is at least 3” in diameter and has sufficient
capacity to prevent the tank from overflowing
Piping connections on drains and overflow pipes allow
ready access to the interior of the pipe for inspection and
cleaning
Bottom of the overflow connection is at least 6” below the
top of the tank
When Must I Provide a Bottom Drain?
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For tanks that contain > 500 gallons of liquid,
unless:
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The tank is equipped with an automatic closing cover
The viscosity of the liquid at normal atmospheric
temperature does not allow the liquid to flow or be pumped
easily
Bottom Drain (Continued)
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Must ensure that the bottom drain:
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Will empty the dip tank during a fire
– Has pipes that permit the contents to be removed in 5 minutes
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Is properly trapped
Discharges to a safe location
Bottom Drain (Continued
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Must be capable of manual and automatic operation
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Manual operations must be from a safe and accessible
location
Must ensure that automatic pumps are used when
gravity flow from the bottom drain is impractical
When Must My Conveyor System Shut
Down Automatically?
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If a conveyor system is used, the system must shut
down automatically:
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If there is a fire
If the ventilation rate drops below requirements
What Ignition and Fuel Sources Must Be
Controlled?
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In each vapor area and any adjacent area:
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All electrical wiring and equipment conform requirements
of Subpart S
– Except as permitted in 1910.126
– There are no flames, spark-producing devices, or other surfaces that
are hot enough to ignite vapors
Ignition and Fuel Sources (Continued)
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Portable container used to add liquid to the tank is
electrically bonded and grounded
Heating systems used in a drying operation that
could cause ignition:
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Is installed in accordance with NFPA
Has adequate mechanical ventilation that operates before
and during drying operation
Ignition and Fuel Sources (Continued)
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Shuts down automatically if any ventilating fan fails to
maintain adequate ventilation
All vapor areas are free of combustible debris
Rags and other contaminated material placed in approved
waste cans immediately after use
Waste can contents are properly disposed of at the end of
each shift
Post "no smoking" sign near each tank
What Fire Protection Must I Provide?
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Required for:
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Any tank with a capacity of at least 150 gallons or a liquid
surface area of at least 4’
Any hardening or tempering tank with a capacity of at least
500 gallons or a liquid surface area of at least 25’
Fire Protection (Continued)
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For vapor areas, you must provide:
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Manual fire extinguishers for flammable and combustible
liquid fires
Automatic fire-extinguishing system, Subpart L
Fire Protection (Continued)
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May substitute a cover that is closed by an
approved automatic device for the automatic fireextinguishing system if the cover:
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Can also be activated manually
Is noncombustible or tin-clad, with the enclosing metal
applied with locked joints
Is kept closed when the tank is not in use
To What Temperature May I Heat a Liquid in
a Dip Tank?
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Must maintain the temperature of the liquid:
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Below the liquid's boiling point
At least 100 deg. F below the liquid's autoignition
temperature
Additional Requirements for Special Dipping
and Coating Operations - 1910.126
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In addition to the requirements in 1910.123 -125,
must comply with any requirement that applies to
your operation
What Additional Requirements Apply to
Hardening or Tempering Tanks?
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Must ensure that hardening or tempering tanks:
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Are located as far as practicable from furnaces
Are on noncombustible flooring
Have noncombustible hoods and vents for venting to the
outside
– Vent ducts must be treated as flues and kept away from combustible
materials, particularly roofs
Hardening or Tempering (Continued)
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Must equip each tank with an alarm that will sound
if the temperature of the liquid comes within 50 deg.
F of its flashpoint (the alarm set point)
When practicable, provide each tank with a limit
switch to shut down the conveyor supplying work to
the tank
Hardening or Tempering (Continued)
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If the temperature of the liquid can exceed the alarm
set point, equip the tank with a circulating cooling
system
If the tank has a bottom drain, it may be combined
with the oil-circulating system
Must not use air under pressure when filling the
tank or agitate liquid
What Additional Requirements Apply to
Flow Coating?
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Must use a direct low-pressure pumping system or
a 10-gallon or < gravity tank to supply the paint for
flow coating
In case of fire, an approved heat-actuated device
must shut down the pumping system
Must ensure that the piping is substantial and
rigidly supported
What Additional Requirements Apply to Roll
Coating, Roll Spreading, or Impregnating?
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When using a flammable or combustible liquid with
a flashpoint < 140 deg. F, prevent static electricity
by:
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Bonding and grounding all metallic parts (including
rotating parts)
Installing static collectors
Maintaining a conductive atmosphere (for example, one
with a high relative humidity)
What Additional Requirements Apply to
Vapor Degreasing Tanks?
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Must ensure that the condenser or vapor-level
thermostat keeps the vapor level at least 36” or 1/2half the tank width, whichever is less, below the top
of the tank
Vapor Degreasing (Continued)
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When gas as fuel is used to heat the tank liquid,
prevent solvent vapors from entering the air-fuel
mixture
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Make the combustion chamber airtight (except for the flue
opening)
Flue must be made of corrosion-resistant material
It must extend to the outside
Must install a draft diverter if mechanical exhaust is used
on the flue
Vapor Degreasing (Continued)
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Must not allow the temperature of the heating
element to cause a solvent or mixture to decompose
or to generate excessive amount of vapor
What Additional Requirements Apply to
Cyanide Tanks?
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Cyanide tanks must have a dike or other safeguard
to prevent cyanide from mixing with an acid if a dip
tank fails
Additional Requirements For Spray
Cleaning And Degreasing Tanks?
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If you spray a liquid in the air over an open-surface
cleaning or degreasing tank, control the spraying
by:
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Enclosing the spraying operation
Using mechanical ventilation to provide enough inward air
velocity to prevent the spray from leaving the vapor area
What Additional Requirements Apply to
Electrostatic Paint Detearing?
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Must use only approved electrostatic equipment in
paint-detearing operations
Electrodes must be substantial, rigidly supported,
permanently located, and effectively insulated from
ground by nonporous, noncombustible, clean, dry
insulators
Must use conveyors to support any goods being
paint deteared
Electrostatic Paint (Continued)
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Must ensure that material being electrostatically
deteared are not manually handled
Must maintain a minimum distance of twice the
sparking distance between material being
electrostatically deteared and the electrodes or
conductors of the electrostatic equipment
Minimum distance must be displayed near the
equipment
Electrostatic Paint (Continued)
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Must ensure that the electrostatic equipment has
automatic controls that immediately disconnect the
power supply to the high-voltage transformer and
signal the operator if:
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Ventilation or the conveyors fail to operate
Material being electrostatically deteared come within twice
the sparking distance of the electrodes or conductors of
the equipment
A ground occurs anywhere in the high-voltage system
Electrostatic Paint (Continued)
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Must use fences, rails, or guards, made of
conducting material and adequately grounded, to
separate paint-detearing operations from storage
areas and from personnel
Electrostatic Paint (Continued)
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To protect paint-detearing operations from fire,
must have:
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Automatic sprinklers
An automatic fire-extinguishing system conforming to the
requirements of Subpart L
To collect paint deposits:
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Provide drip plates and screens
Clean these plates and screens in a safe location