Transcript Confined Space Entry - Environmental Health and Safety

Confined Spaces
“Non-Permit”
“Permit-Required”
ETSU Confined Spaces

Physical Plant’s Confined
Space Policy

Approved October 17, 2003
Confined Space Defined

The space is not designed for continuous
employee occupancy

The space is large enough to enter and
perform work

The space has limited
means of entry and exit
Confined Space Examples
● Tanks
● Vaults
● Manholes
● Pipes
● Boilers
● Tunnels
● Furnaces
● Bins
● Sewers
● Pits
● Hoppers
● Silos
Not Designed for Continuous
Worker Occupancy
• Most confined spaces are not designed to enter
and work in on a regular basis.
• The space encloses materials or processes.
• Occasional worker entry for inspection, repair,
cleanup, maintenance, etc.
Permit-Required Confined Space
A Permit-Required
Confined Space is
a confined space
that has one or
more of the
following
characteristics:
● Contains or has the potential to
contain a hazardous
atmosphere;
● Contains a material that has the
potential for engulfing an
entrant;
● Has an internal configuration
such that an entrant could
become trapped or asphyxiated;
or
● Contains any other serious
safety or health hazard.
Non-Permit Confined Space
● A non-permit confined space does not
contain or, with respect to atmospheric
hazards, have the potential to contain
any hazard capable of causing death of
serious physical harm.
● A permit-required confined space can
be reclassified as a non-permit space.
ENTRY by Entrant
● The act by which a
person passes through
an opening into a
permit-required confined
space.
● Occurs during work
activities when the
entrant’s body breaks
the plane of an opening
into the space
Categorizing the Work Space
• Space large enough to enter &;
• Limited or Restricted entry or exit &;
• Not designed for continuous worker
occupancy.
YES
NO Not a Confined Space
Confined Space
Hazardous Atmosphere
PermitRequired
Confined
Space
Or
YES
Engulfment Hazard
Or
Configuration Hazard
O
r recognized
Any other
serious hazard
NO
Non
PermitRequired
Space
Confined Space Entry
To reclassify a permit-required
confined space, a pre-entry
checklist shall be completed and
certified by an entry supervisor
prior to entry.
The checklist shall contain the date, the location of
the space, and the signature of the person
providing the certification.
Pre-Entry Procedures
Physical Plant employees
shall follow the pre-entry
procedures that establish
safe entry for our employees.
Pre-Entry Checklist
Unfavorable Natural Ventilation
• Lack of air movement in and out of the
space can create an atmosphere much
different than the outside atmosphere.
• Deadly gases can be trapped inside.
• Organic materials can decompose.
• May not be enough oxygen due to
presence of other gases or chemical
reactions such as rusting.
Confined Space Entry - Hazards
Manholes often remain
covered for long periods
of time. Poisonous
gases, such as
hydrogen sulfide
can accumulate inside of
manholes.
CH4
H2 S
Manholes may also
accumulate highly
flammable gases
such as methane.
Oxygen Deficient Atmospheres
19.5 %
15 - 19%
Minimum acceptable oxygen level.
Decreased ability to work strenuously.
Impair coordination. Early symptoms.
12-14%
Respiration increases. Poor judgment.
10-12%
8-10%
Respiration increases. Lips blue.
Mental failure. Fainting. Nausea
Unconsciousness. Vomiting.
6-8%
8 minutes - fatal, 6 minutes - 50% fatal
4-5 minutes - possible recovery.
4-6%
Coma in 40 seconds. Death
Oxygen Enriched Atmospheres
• Oxygen level above 21%.
• Causes flammable and combustible
materials to burn violently when
ignited.
• Never use pure oxygen to ventilate.
• Never store or place compressed
tanks in a confined space.
Flammable Atmospheres
• Critical Factors:



Oxygen content in the air.
Presence of a flammable gas, or vapor
Presence of dust (visibility of 5’ or less)
• Ignition Sources: (Hot Work Permit)



Sparking or electric tool
Welding / cutting operations
Smoking
Hydrogen Sulfide
• Decomposition of materials. Human waste.
• Rotten egg odor at low concentrations.
• Possibly no warning at high concentrations.
PPM
Effect
Time
10 ppm
50 - 100
200 - 300
500 -700
>1000
Permissible Exposure Level
Mild Irritation - eyes, throat
Significant Irritation
Unconsciousness, Death
Unconsciousness, Death
8 Hours
1 Hour
1 Hour
1/2 - 1 Hour
Minutes
Carbon Monoxide
• Odorless, Colorless Gas.
• Combustion By-Product.
• Quickly collapse at high concentrations.
PPM
50
200
600
1000-2000
1000-2000
1000-2000
2000-2500
Effect
Permissible Exposure Level
Slight headache, discomfort
Headache, discomfort
Confusion, nausea, headache
Tendency to stagger
Slight heart palpitation
Unconsciousness
Time
8 Hours
3 Hours
1 Hour
2 Hours
1 1/2 Hours
30 Min.
30 Min.
Confined Space Entry - Hazards
If concentrations of
gases and vapors
are found to be at
harmful levels, the
??
confined space must
be ventilated before
O2
entry.
Fresh Air
Fresh outside
air is blown into
the space to dilute
and remove
contaminants, and
??
supply oxygen.
??
??
O2
O2
O2
Testing The Atmosphere
•
•
Verify presence of safe work
atmosphere.
Test at various depths of a confined
space.
Top,
Middle, Bottom
Always test the
air at various levels
to be sure that the
entire space is safe.
Good air near the
opening does NOT
mean there is good
air at the bottom!
• Methane is lighter than air.
• Carbon Monoxide is the
same as air.
• Hydrogen Sulfide is
heavier than air.
Emergency Procedures
Should conditions develop which require extrication, and the
entrant cannot get out of the confined space on their own,
the attendant must call for emergency assistance at once!
Call
911
CAUTION
Opening in Ground
Keep Out !
BARRIERS and
SIGNS must be
placed around any
openings to protect
the entrants and
passers-by.
Contractor Confined Space Entry
• Contractors must follow their own established
confined space entry procedure.
• A joint entry by ETSU employees and contractors
will be coordinated by an ETSU entry supervisor.
• Contractors must supply their own air monitors.
• Contractors are required to contact a Physical
Plant representative at the completion of an entry
to discuss any hazards confronted during the entry.
Ventilation
• First option to correct problems.
• Must be aware of hazards you are trying to
correct in the confined space.
• Air intake in a safe location to draw fresh air
only.
• Continuous ventilation whenever possible.
• Retest the confined space before entry.
Isolation
• Locking and tagging out electrical sources.
• Blanking and bleeding pneumatic and
hydraulic lines.
• Disconnecting mechanical drives and shafts.
• Securing mechanical parts.
• Blanking sewer and water flow.
• Locking and tagging out shutoff valves.
Respirators
• Air-Purifying Respirators



Filter dangerous substances from the air.
Must know the type and amount of
hazardous substance present in the
confined space.
NEVER use with oxygen deficiency!
• Air-Supplying Respirators

Deliver a safe supply of breathing air from
a tank or an uncontaminated area nearby.
Entrant Responsibilities





Know the hazards of the space.
Proper use of equipment in space.
Communicate with the attendant.
Places his/her lockout/tagout device on
isolation point(s) before entry
Alert the attendant whenever
they recognize a dangerous situation.
 Detect a prohibited condition

Entrant Responsibilities

Exit from the space as quickly as possible
whenever:
An order to evacuate is given by the
attendant or entry supervisor
 The entrant recognizes any warning signs of
exposure or a dangerous situation
 The entrant detects a prohibited condition.
 The multi-gas detector alarms

Attendant Responsibilities




Knows the hazards that might be faced
during entry
Aware of possible behavioral effects of
hazard exposure to the entrant
Maintains a count of entrants in the space
Remains outside the permit space during
entry operations
Attendant Responsibilities




Communicates with the entrants and
alerts if evacuation is needed.
Monitors activities inside and outside the
space determining if it is safe.
Performs non-entry rescue (tripod, nonentry retrieval device)
Summon rescue services if person needs
assistance to escape space (911)
Entry Supervisor Responsibilities




Knows the hazards that may be faced during
entry, including mode, signs or symptoms, and
consequences of exposure.
Verifies that the appropriate entries have been
made on the permit.
Verifies that all tests specified by the permit
have been conducted
Verifies that all procedures and equipment
specified by the permit are in place before
approving the permit and allowing entry
Entry Supervisor Responsibilities

Terminates the entry and cancels the
permit as required when:
The entry operations have been completed
 A condition that is not allowed under the
entry permit arises in or near the space
(Note: The employer shall retain the permit for
at least 1 year. Entry supervisor turn in
permits to Health & Safety at the Physical
Plant.)

Entry Supervisor Responsibilities



Verifies that rescue services are available
Removes unauthorized individuals who
attempt to enter the permit space
Verifies that acceptable entry conditions
are maintained during entry and that all
requirements of the permit are met.
Summary

Confined spaces are
generally classified
into two categories
 Permit Required
•

Have the potential
to contain serious
safety and health
hazards
Non Permit
Required
Summary

Some common confined
space hazards include:




Atmospheric hazards
Moving parts
Tight spaces
Engulfment hazards
Summary

The Company’s “entry permit system” is
designed to ensure that confined space
hazards are controlled during the entry
process
Summary

The entry supervisor
makes sure all entry
procedures are
followed as outlined
on the entry permit
Summary


The standby attendant
acts as the eyes and
ears of the entry
process, monitoring
conditions both inside
and outside the space
The standby attendant
may not enter the
confined space during
a rescue
Summary


The confined space
entrants are the only ones
authorized to enter a
confined space
Entrants must know all
potential hazards, maintain
communications with the
attendant and immediately
exit the space when
instructed to evacuate
Summary


Each member of the entry
team has a specific role to
play in the entry process
By following the
requirements of the entry
permit system, the entry
team is able to work
safely in confined spaces