Examples of Permit-Required Confined Space
- Example 1
- Workplace: Sewer entry
- Example 2
- Workplace: Meat and poultry rendering plants
- Example 3
- Workplace: Workplaces where tank cars, trucks, and
trailers, dry bulk tanks and trailers, railroad tank cars, and similar portable
tanks are fabricated or serviced
Workplace. Sewer entry.
Potential hazards. The employees could be exposed
to the following:
Presence of toxic gases.
Equal to or more than 10 ppm hydrogen sulfide measured as an 8-hour
time-weighted average. If the presence of other toxic contaminants is suspected,
specific monitoring programs will be developed. If the presence of other toxic contaminants is
suspected, specific monitoring
programs will be developed.
Presence of explosive/flammable gases.
Equal to or greater than 10% of the lower flammable limit
Oxygen Deficiency. A concentration of oxygen in the
atmosphere equal to or less than 19.5% by
A. ENTRY WITHOUT PERMIT/ATTENDANT
Certification. Confined spaces may be entered
without the need for a written permit or attendant
provided that the space can be maintained in a safe condition for entry by
alone, as provided in 1910.146(c)(5). All spaces shall be considered
spaces until the pre-entry procedures demonstrate otherwise. Any employee
required or permitted
to pre-check or enter an enclosed/confined space shall have successfully
completed, as a minimum,
the training as required by the following sections of these procedures.
A written copy of operating and rescue procedures as required by these procedures shall be at the
work site for the duration of the job. The Confined Space Pre-Entry Check
List must be completed by the LEAD WORKER before entry into a confined space.
This list verifies completion of items listed below. This check list shall be
kept at the job site for duration of the job. If circumstances dictate an
interruption in the work, the permit space must be re-evaluated and a new check
list must be completed.
Control of atmospheric and engulfment hazards.
Pumps and Lines. All pumps and lines which may
reasonably cause contaminants to flow into the
space shall be disconnected, blinded and locked out, or effectively isolated
by other means to
prevent development of dangerous air contamination or engulfment. Not all
laterals to sewers or
storm drains require blocking.
However, where experience or knowledge of industrial use
indicates there is a reasonable potential
for contamination of air or engulfment into an occupied sewer, then all
affected laterals shall be
blocked. If blocking and/or isolation requires entry into the space the
provisions for entry into a
permit-required confined space must be implemented.
Surveillance. The surrounding area shall be
surveyed to avoid hazards such as drifting vapors from
the tanks, piping, or sewers.
Testing. The atmosphere within the space will be
tested to determine whether dangerous air
contamination and/or oxygen deficiency exists. Detector tubes, alarm only
gas monitors and
explosion meters are examples of monitoring equipment that may be used to
test permit space
atmospheres. Testing shall be performed by the LEAD WORKER who has
the Gas Detector training for the monitor he will use. The minimum
parameters to be monitored are
oxygen deficiency, LFL, and hydrogen sulfide concentration. A written record
of the pre-entry test results shall be made and kept at the work site for the duration of the job.
The supervisor will certify
in writing, based upon the results of the pre-entry testing, that all
hazards have been eliminated. Affected employees shall be able to review the testing results. The most
hazardous conditions shall
govern when work is being performed in two adjoining, connecting spaces.
Entry Procedures. If there are no non-atmospheric
hazards present and if the pre-entry tests show
there is no dangerous air contamination and/or oxygen deficiency within the
space and there is no reason to believe that any is likely to develop, entry into and work within
may proceed. Continuous
testing of the atmosphere in the immediate vicinity of the workers within
the space shall be
accomplished. The workers will immediately leave the permit space when any
of the gas monitor
alarm set points are reached as defined. Workers will not return to the area
until a SUPERVISOR
who has completed the gas detector training has used a direct reading gas
detector to evaluate the
situation and has determined that it is safe to enter.
Rescue. Arrangements for rescue services are not
required where there is no attendant. See the
rescue portion of section B, below, for instructions regarding rescue
planning where an entry permit
B. ENTRY PERMIT-REQUIRED
Permits Confined Space Entry Permit. All spaces
shall be considered permit-required
confined spaces until the pre-entry procedures demonstrate otherwise. Any
required or permitted to pre-check or enter a permit-required confined space
successfully completed, as a minimum, the training as required by the
following sections of
these procedures. A written copy of operating and rescue procedures as
required by these procedures shall be at the work site for the duration of the job. The
Confined Space Entry
Permit must be completed before approval can be given to enter a
space. This permit verifies completion of items listed below. This permit
shall be kept at the
job site for the duration of the job. If circumstances cause an interruption
in the work or a
change in the alarm conditions for which entry was approved, a new Confined
Permit must be completed.
Control of atmospheric and engulfment hazards.
Surveillance. The surrounding area shall be
surveyed to avoid hazards such as drifting
vapors from tanks, piping or sewers.
Testing. The confined space atmosphere shall be
tested to determine whether dangerous air
contamination and/or oxygen deficiency exists. A direct reading gas monitor
shall be used.
Testing shall be performed by the SUPERVISOR who has successfully completed
detector training for the monitor he will use. The minimum parameters to be
oxygen deficiency, LFL and hydrogen sulfide concentration. A written record
of the pre-entry test results shall be made and kept at the work site for the
duration of the job.
Affected employees shall be able to review the testing
results. The most hazardous
conditions shall govern when work is being performed in two adjoining,
Space Ventilation. Mechanical ventilation systems,
where applicable, shall be set at 10% outside air. When possible, open additional manholes to increase air
portable blowers to augment natural circulation if needed. After a suitable
repeat the testing. Entry may not begin until testing has demonstrated that
atmosphere has been eliminated.
Entry Procedures. The following procedure shall be
observed under any of the following
- Testing demonstrates the existence of dangerous or
deficient conditions and additional ventilation cannot reduce concentrations to safe levels;
- The atmosphere tests as safe but unsafe conditions can
reasonably be expected to develop;
- It is not feasible to provide for ready exit from
spaces equipped with automatic fire suppression systems and it is not practical or safe to deactivate such
- An emergency exists and it is not feasible to wait for
pre-entry procedures to take effect.
All personnel must be trained. A self contained breathing
apparatus shall be worn by any
person entering the space. At least one worker shall stand by the outside of
the space ready
to give assistance in case of emergency. The standby worker shall have a
breathing apparatus available for immediate use. There shall be at least one
worker within sight or call of the standby worker. Continuous powered
be maintained between the worker within the confined space and standby
If at any time there is any questionable action or
non-movement by the worker inside, a
verbal check will be made. If there is no response, the worker will be
Exception: If the worker is disabled due to falling
or impact, he/she shall not be removed
from the confined space unless there is immediate danger to his/her life.
department rescue personnel shall be notified immediately. The standby
worker may only
enter the confined space in case of an emergency (wearing the self contained
apparatus) and only after being relieved by another worker. Safety belt or
attached lifeline shall be used by all workers entering the space with the
free end of the line
secured outside the entry opening. The standby worker shall attempt to
remove a disabled
worker via this lifeline before entering the space.
When practical, these spaces shall be entered through side
openings - those within 3 ½ feet
(1.07 m) of the bottom. When entry must be through a top opening, the safety
belt shall be of
the harness type that suspends a person upright and a hoisting device or
shall be available for lifting workers out of the space.
In any situation where their use may endanger the worker,
use of a hoisting device or safety
belt and attached lifeline may be discontinued.
When dangerous air contamination is attributable to
flammable and/or explosive substances,
lighting and electrical equipment shall be Class 1, Division 1 rated per
Code and no ignition sources shall be introduced into the area.
Continuous gas monitoring shall be performed during all
confined space operations. If alarm
conditions change adversely, entry personnel shall exit the confined space
and a new
confined space permit issued.
Rescue. Rescue services must be notified of the
entry prior to the actual entry of the space.
Where immediate hazards to injured personnel are present, workers at the
implement emergency procedures to fit the situation.
Workplace. Meat and poultry rendering plants.
Cookers and dryers are either batch or continuous in their
operation. Multiple batch
cookers are operated in parallel. When one unit of a multiple set is shut
down for repairs,
means are available to isolate that unit from the others which remain in
Cookers and dryers are horizontal,
cylindrical vessels equipped with a center, rotating shaft and agitator paddles
or discs. If the inner shell is jacketed, it is usually heated with steam at
pressures 150 psig (1034.25 kPa). The rotating shaft assembly of the
continuous cooker or dryer is also steam heated.
Potential Hazards. The recognized hazards
associated with cookers and dryers are the risk
that employees could be:
- Struck or caught by rotating
- Engulfed in raw material or
hot, recycled fat;
- Burned by steam from leaks into
the cooker/dryer steam jacket or the condenser duct system if steam valves are not
properly closed and locked out;
- Burned by contact with hot
metal surfaces, such as the agitator shaft assembly, or
inner shell of the cooker/dryer;
- Heat stress caused by warm
atmosphere inside cooker/dryer;
- Slipping and falling on grease
in the cooker/dryer;
- Electrically shocked by faulty
equipment taken into the cooker/dryer;
- Burned or overcome by fire or
products of combustion; or
- Overcome by fumes generated by
welding or cutting done on grease covered surfaces.
Permits. The supervisor in this case is always
present at the cooker/dryer or other permit
entry confined space when entry is made. The supervisor must follow the
procedures described in the entry permit in preparing for entry, and ensure
protective clothing, ventilating equipment and any other equipment required
by the permit
are at the entry site.
Control of hazards. Mechanical. Lock out main power
switch to agitator motor at main power
panel. Affix tag to the lock to inform others that a permit entry confined
space entry is in
Engulfment. Close all valves in the raw material
blow line. Secure each valve in its closed
position using chain and lock.
Attach a tag to the valve and chain warning that a permit
entry confined space entry is in
progress. The same procedure shall be used for securing the fat recycle
Burns and heat stress. Close steam supply valves to
jacket and secure with chains and tags.
Insert solid blank at flange in cooker vent line to condenser manifold duct
cooker/dryer by opening access door at discharge end and top center door to
ventilation throughout the entry. If faster cooling is needed, use a
portable ventilation fan to
increase ventilation. Cooling water may be circulated through the jacket to
outer and inner surface temperatures of cooker/dryers faster. Check air and
temperatures in cooker/dryer to assure they are within acceptable limits
before entering, or use proper protective clothing.
Fire and fume hazards. Careful site preparation,
such as cleaning the area within 4 inches
(Published by the Connecticut Department of Labor, Project Management
Office.16 cm) of all welding or torch cutting operations, and proper ventilation
are the preferred
controls. All welding and cutting operations shall be done in accordance
requirements of 29 CFR Part 19, Subpart Q, OSHA's welding standard. Proper
ventilation may be achieved by local exhaust ventilation, or the use of portable
ventilation fans, or a
combination of the two practices.
Electrical shock. Electrical equipment used in
cooker/dryers shall be in serviceable
Slips and falls. Remove residual grease before
Attendant. The supervisor shall be the attendant
for employees entering cooker/dryers.
Permit. The permit shall specify how isolation
shall be done and any other preparations
needed before making entry. This is especially important in parallel
cooker/dryers so that the entire operation need not be shot down to allow
safe entry into one
Rescue. When necessary, the attendant shall call
the fire department as previously arranged.
Workplace. Workplaces where tank cars, trucks, and
trailers, dry bulk tanks and trailers,
railroad tank cars, and similar portable tanks are fabricated or serviced.
Sources of hazards. In addition to the mechanical hazards arising from
the risks that an entrant would be injured due to contact with
components of the tank or the tools being used, there is also
the risk that a worker could be injured by breathing fumes from
the welding materials or mists or vapors from materials used to
coat the tank interior. In addition, many of these vapors and
mists are flammable, so the failure to properly ventilate a tank
could lead to fire or explosion.
During fabrication. These tanks and dry-bulk carriers are entered
repeatedly throughout the fabrication process. These products are not configured
identically, but the manufacturing processes by which they are made are very
Control of hazards
Welding. Local exhaust ventilation shall be used to
remove welding fumes once the tank or
carrier is completed to the point that workers may enter and exit only
through a manhole.
(Follow the requirements of 29 CFR 19Published by the Connecticut Department
of Labor, Project Management Office, Subpart Q, OSHA's welding standard at all times). Welding gas tanks may never be brought into a tank or carrier that
is a permit entry
Application of interior coatings/linings.
Atmospheric hazards shall be controlled by forced air
ventilation sufficient to keep the atmosphere concentration of flammable
Published by the Connecticut Department of Labor, Project Management Office%
of the lower flammable limit (LFL) (or lower explosive limit (LEL), whichever
term is used locally). The appropriate respirators are provided and shall be
used in addition to providing forced ventilation if the forced ventilation does
acceptable respiratory conditions.
Permits. Because of the repetitive nature of the
entries in these operations, an "Area Entry
Permit" will be issued for a 1 month period to cover those production areas
where tanks are
fabricated to the point that entry and exit are made using manholes.
Authorization. Only the area supervisor may
authorize an employee to enter a tank within
the permit area. The area supervisor must determine that conditions in the
tank trailer, dry
bulk trailer or truck, etc. meet permit requirements before authorizing
Attendant. The area supervisor shall designate an
employee to maintain communication by
employer specified means with employees working in tanks to ensure their
attendant may not enter any permit entry confined space to rescue an entrant
or for any
other reason, unless authorized by the rescue procedure and, and even then,
only after calling
the rescue team and being relieved by an attendant or by another worker.
Communications and observation. Communications
between attendant and entrant(s) shall be maintained throughout entry. Methods of communication that may be
specified by the
permit include voice, voice powered radio, tapping or rapping codes on tank
tugs on a rope, and the attendant's observation that work activities such as
grinding, welding, spraying, etc., which require deliberate operator control
normally. These activities often generate so much noise that the necessary
protection makes communication by voice difficult.
Rescue procedures. Acceptable rescue procedures
include entry by a team of
employee-rescuers, use of public emergency services, and procedures for
tank. The area permit specifies which procedures are available, the area
the final decision based on circumstances. (Certain injuries may make it
necessary to breach
the tank to remove a person rather than risk additional injury by removal
existing manhole). However, the supervisor must ensure that no breaching
for rescue would violate terms of the entry permit. For instance, if the
tank must be
breached by cutting with a torch, the tank surfaces to be cut must be free
of volatile or
combustible coatings within 4 inches (.16 cm) of the cutting line and
within the tank must be below the LFL.
Retrieval line and harnesses. The retrieval lines
and harnesses generally required under
this standard are usually impractical for use in tanks because the internal
configuration of the
tanks and their interior baffles and other structures would prevent rescuers
from hauling out
injured entrants. However, unless the rescue procedure calls for breaching
the tank for
rescue, the rescue team shall be trained in the use of retrieval lines and
removing injured employees through manholes.
Sources of hazards. In addition to facing the potential hazards
encountered in fabrication or
manufacturing, tanks or trailers which have been in service may contain
dangerous materials, whether left over from the transportation of hazardous
Repair or service of "used" tanks and bulk trailers
generated by chemical or bacterial action on residues of non-hazardous
Control of atmospheric hazards. A "used" tank shall
be brought into areas where tank entry
is authorized only after the tank has been emptied, cleansed (without
employee entry) of any
residues, and purged of any potential atmospheric hazards.
Welding. In addition to tank cleaning for control
of atmospheric hazards, coating and surface
materials shall be removed 4 inches (.16 cm) or more from any surface area where
welding or other torch work will be done and care taken that the atmosphere within
the tank remains
well below the LFL. (Follow the requirements of 29 CFR 19, Subpart Q, OSHA's
welding standard, at all times).
Permits. An entry permit valid for up to 1 year
shall be issued prior to authorization of entry
into used tank trailers, dry bulk trailers or trucks. In addition to the
requirement, this permit shall require the employee safeguards specified for
fabrication or construction permit areas.
Authorization. Only the area supervisor may
authorize an employee to enter a tank trailer,
dry bulk trailer or truck within the permit area. The area supervisor must
determine that the
entry permit requirements have been met before authorizing entry.
April 27, 2018