Ihab Saad – Confined Spaces
AI: Summary ©
The speakers discuss OSHA standards and confined spaces in construction, including definition and permit requirements, internal configuration, access portals, and elevation. They provide four descriptions of the space and its characteristics for rescue procedures, emphasizing the importance of avoiding hazards like toxic gases and smoke and maintaining proper air handling. The speakers also discuss the roles of entry supervisors, the use of protective equipment, and communication procedures for attendance and entrance.
AI: Summary ©
Music. Hello again.
Today we're going to talk about confined spaces in construction.
So we're going to have an overview of OSHA standards and unconfined
and confined space hazards. So first of all, we're going to
identify what is considered a confined space, and then we're
going to talk about different responsibilities of different
personnel who might be involved with that confined space, and how
to have the maximum protection when we have to do some work
inside a confined space.
So the objectives are going to be to define the confined space,
define permit required confined spaces. OSHA standards on confined
space. And finally, understand what are the major hazards and how
to protect ourselves against these hazards in a confined space.
So the definition, first of all, a confined space, According to OSHA,
is a space that it has to meet all of these three conditions, it is
large enough to get into and work inside of. So if it's just a very
small space where no one can get into, it's not considered a
confined space in this in this case, number two, it has a
restricted means of entry or exit. Might have a small entry hole, for
example, in this case, would be a confined space, and it's not
designed for continuous occupancy. So for example, if you have a
small closet for storage of materials or equipment or
whatever, but it's that closet is large enough for someone to get
inside and work inside, then it would not be considered the
confined space, because the confined space is not designed for
continuous occupancy.
So when we talk about permit required confined space, not every
confined space is going to require a permit. So in order to qualify
as a permit, required confined space, or PRCs,
its space is gonna have to satisfy the first definition of being a
confined space, which we saw on the previous slide, and then it is
subject to unsafe atmospheres, toxic atmosphere or flammable
contents or oxygen deficient does not have enough oxygen for
sustainable breathing. So if it has any of these three conditions,
not all of them, just any of these, in addition to being a
confined space, then for someone to work inside that confined
space, they have to have a specific and special permit
exam. Examples? Well, basically, this lecture is going to talk
about the scope and application, the definitions, general
requirements, including the written plans. What are the permit
required confined spaces? What is the permit system? What is the
entry permit? What kind of training the employees have to be
subject to. What are the duties of the authorized entrance? Duties of
attendance? Notice the definitions here. We have something called
authorized entrant. We have something called attendant. We
have something called entry supervisors. So these are three
different positions or occupations. We're going to talk
about them in detail, and then we're going to talk about the
rescue and emergency services if someone loses consciousness inside
that confined space that requires a permit, and finally, employee
participation in that safety program.
This is related to Appendix A all of these are inside in your book,
in your code book, permit required confined space decision flow
chart. Appendix B, procedures for atmospheric testing. Appendix C,
examples of permit required confined space programs. Appendix
V, confined space pre entry checklist. What should you check
before someone enters a confined space requiring a permit? Appendix
E, sewer system entry and appendix F rescue team or rescue service
evaluation criteria.
So we're going to talk about some of the characteristics of a
confined space. First of all, the internal configuration. What may
make it even more difficult to work with? In addition to the
previous, previous conditions that we have mentioned. We're going to
talk about the elevation. We're going to talk about the portal
side size, which is the entry or exit portal, the way through which
you get in or out, and space access orientation.
So is it horizontal? Is it going to be vertical? And so on.
With the internal configuration, we have either an open confined
space or an obstructed confined space. An open confined space has
no obstacles within the space. Example is a water tank, water
tank, huge water tank, used for storage of water. It has a
limited.
Uh, entry port. It's not used or supposed to be for permanent
occupancy and so on. And the other option is, in this case, rescue is
less difficult, because, again, there are no obstacles that we
have to maneuver around. The other one would be an obstructed,
confined space, which has obstacles including baffles,
mixing blades, scaffolds on the inside of that space. In this
case, rescue is going to be much more difficult. To give you an
example here, if we have the drum of a transit mixer,
that's a definitely a confined space,
it is obstructed because it has baffles on the inside. It has the
blades that rotate the concrete inside that the drum. And it has a
limited portal. It's sloped. So again, access by itself is not
going to be idiot the easiest thing, so in this case, rescue is
definitely more difficult than the previous exam.
The second one is elevation. We have either non elevated or
elevated. If it's non elevated, Access Portal is less than four
feet above grade or above ground, above the level where you are
entering from. So even if it's on a suspended slab, it's less than
four feet above that slab, the surface of the slab, in this case,
again, rescue is less difficult, because no one has to jump in. You
can just
get in without much hardship. The other one is elevated. If the
Access Portal is four feet or more above the grade, you have to
remember that cutoff number, which is the four feet. So if the Access
Portal is four feet or more above the grade, then rescue is more
difficult. So if it has obstacles and it's elevated, that definitely
make it, makes it a double way.
The third one is the portal side. Okay. Size. The Portal size
unrestricted, is an opening of larger than 24 inches in the least
dimension. So if it's a rectangle, the shorter side is going to be 24
inches. If it's a circular port of entry, then it's going to be the
diameter that has to be at least 24 inches. Then in this case,
again, rescue is less difficult restricted an opening of 24 inches
or less in the least dimension. In this case, rescue is more
difficult. So again, we talked about the elevation, we talked
about the obstruction, and we talked about the portal size. The
fourth one is going to be the orientation, the space access
orientation, if it's horizontal, then most likely the portal is
going to be easier to access. Someone can even crawl in if the
portal is located on the side of the permit space, rescue is
normally less difficult. But if it's vertical, and the portal is
at the top of it, most likely is going to be more than four feet
high. So if the portal is located on the top or bottom of the permit
space, vertical portals may require special patient packaging
to rescue to extract the employee from that space. So result, rescue
is normally more difficult. So these are four descriptions or
characteristics of confined spaces that we have to take into
consideration when designing our program and our rescue procedures.
Here are some examples. This is a storage tank. Now, which
conditions are going to be here? If it has baffles on the inside,
then it's going to be obstructed, obviously, that's elevated, most
likely that's going to be more than four feet above ground. Well,
although the storage tank itself is horizontal, but the entry
portal is vertical, not horizontal. Now, depending on the
dimensions of that entry portal, the size, if this is less than 24
inches, that's going to make it even more difficult. Silo again,
although it is vertical, but the entry portal is horizontal. It
might or might not have baffles. So again,
it's going to have some of the limitations of a confined space.
And obviously a silo is not designed for permanent occupancy,
and there's going to be lack of oxygen inside silos. Many people
unfortunately get trapped inside and they die.
A pipeline, although it's open from both sides, but again, it
might be too long, something like a culvert here, for example.
Again, it's at we can't even say that it's at ground level, because
it's on water in this case, which makes even things even much more
difficult to access it and extract people from the inside. So again,
this is these are examples of confined spaces.
Now we have to learn about some toxic gasses and their weight and
their volume and their density, whether they are lighter than air.
They're gonna float to the top, or they are heavier than air, so
they're gonna sink to the bottom. So we have here, for example,
three killers, three toxic gasses. Gasses. One of them is methane,
which is lighter than air, so it's gonna accumulate close to the top
surface.
This is a manhole, for example,
carbon monoxide that's called the silent killer because it's
odorless, colorless and you can distinguish it. That's why,
unfortunately, even in residences, you might have the carbon monoxide
detector that can detect an increase in the concentration of
carbon monoxide, which deprives the air of its oxygen, trying to
become carbon dioxide. So the price the air of the oxygen,
that's why it's asphyxiating. And the third one is the hydrogen
sulfide, H, 2s which is heavier than air, and that sinks to the
bottom. So if you are in an environment that has methane,
crawl because the methane is going to move above if you are an
environment that has hydrogen sulfide, then stand up, because,
again, it's going to try to sink to the bottom. If you are an
environment that has carbon monoxide, definitely get out,
because it's going to be suspended in the middle, depending on the
height of that confined space.
Here, are, again, some examples of confined spaces. You kind of need
a ladder to access it, and that hopefully is going to be more than
24 inches in diameter.
So here, for example, we have different people helping the
entrant,
the person who's going to work inside, and obviously they have
the proper breathing apparatus, like a scuba diving gear with
compressed air on their back, so and they have the gas mask and or
the oxygen mask and everything. So they can work inside the confined
space that has either noxious gasses or poisonous gasses or
flammable gasses or even lack of oxygen.
Some other precautions would include, for example, having a
ventilating fan and a trunk hose to keep bringing fresh renewing
the fresh air inside the confined space, if you're going to do any
welding inside the confined space, or if you're going to do any
painting which has some fumes that emanate from that paint. So in
this case, you need to refresh and renew the air inside that confined
space.
And we have either air purifying respirators,
which can either be a half mask that covers only the nose and
mouth, or it can be a full face piece that covers also the eyes,
which might be affected by the toxic fumes. So do not use in
oxygen deficient atmosphere, because that does not provide
oxygen. All it does is purify the existing air. So if the existing
air is deficient in oxygen, then these are going to be totally
useless, therefore do not use in oxygen deficient atmospheres.
On the other hand, air supplying respirators, these can be used in
oxygen deficient atmospheres because here it has the air either
attached through a hose to the tanks or carried on the back,
which is the self contained breathing apparatus, SCBA, scuba,
called scuba, basically, and here's the supplied air respirator
with auxiliary escape only SCBA. So there's going to be a tiny,
maybe they're going to be a tiny canister of oxygen just for the
escape, but otherwise it's going to be totally separate from the
person working inside the confined space.
Some things that you should know about the the atmosphere inside
the confined space, that there's a certain limit within which you
should not work with oxygen, 6%
by volume. In this case, it's going to be different, difficult
breathing. Death is going to happen in minutes
if it's less than 19 and a half percent
oxygen concentration, minimum for the safe entry. So do not enter
the confined space if the the oxygen concentration is less than
19 and a half percent, let's say 20%
23 and a half percent is fine. That's called oxygen enriched
at 16% oxygen concentration, you're gonna have impaired
judgment and heavy breathing at 14% is gonna be faulty judgment,
and rapid fatigue at 6% is going to be almost impossible to
breathe, and that's going to cause asphyxiation. So the safe range is
anywhere above 19 and a half, and this is the dangerous range with
its different danger limits.
Now, in order for an ignition to happen.
Ignition requires three different things. First of all, a flammable
atmosphere, which is going to result from air. These three
components, air, you have to have air to add to help the combustion
gas, vapor or dust, that's the combustible and source of ignition
that's going to cause a spark to ignite that combustible in the
presence of air. So this is the ignition triangle that we try to
avoid
forming these three conditions at the same time.
Now let's talk about the different responsibilities of people who are
going to be dealing with permit required confined spaces.
The first one is the authorized entrant, and that's going to be
authorized by the employer to enter a permit required confined
space. That's the definition authorized by the employer to
enter a permit, confined space, permit requiring confined space.
So that's the person who's going to work inside that confined
space.
All employees required to enter into confined spaces must be
instructed as to the nature of the hazard involved, the necessary
precautions to be taken and the use of protective and emergency
equipment required. So to become an authorized entrant, you have to
satisfy these three conditions. You have to know what are the
natures that what's the nature of the hazards involved, whether it's
oxygen deficiency or toxic fumes or whatever. You have to know what
are the necessary precautions to be taken, whether you have to work
at a certain level because the gas is going to sink to the bottom, or
what kind of protective equipment and you should have on you when
entering that confined space, and what are the different symptoms of
exposure to that hazard, and how You should leave that space
immediately.
So the duties of the authorized entrant is to know the hazards
regarding the space, know the signs or symptoms and consequences
of the exposure to hazardous atmosphere. So if you feel dizzy,
for example, or if you cannot breathe easily, that's a sign of
oxygen, oxygen deficiency, know how to use the equipment properly
and communicate with the attendant, which is the second
person here, to enable attendant to monitor the entrance status. So
the entrant has to satisfy all of these four conditions.
Duties of the authorized entrance also include exit from space as
soon as possible, whenever an evacuation order is given by the
attendant, or an evacuation alarm is activated, which might respond
to oxygen, monocyte, for example, or the detection of a certain gas
or fume or smoke, symptoms are observed Regarding exposure to
hazardous substances, whether these are reflected through a
change in the color of the skin, for example, or something like
that.
So as we just mentioned, you exit from the space as soon as possible
when an evacuation order is given or an evacuation alarm is
activated, or symptoms are observed regarding exposure to
hazardous substances or other prohibitive, prohibitive condition
is detected. So for example, if there's a lack of visibility or or
something else that's going to be preventing you from working
properly, instead in that confined space,
going back to the definitions we learned about the entrant. So the
second position that we talk about is the attendant. The attendant is
a person stationed outside who monitors the authorized entrance
and performs certain other duties. So that's someone who basically is
there to keep an eye on the entrant and make sure that
everything is going fine inside that confined space.
And some of the duties of the attendance very similar to the
duties of the entrant, they should know the hazards regarding the
space, know the signs or symptoms and consequences of exposure to
the hazardous atmospheres, is aware of the behavior effects of
exposures to hazardous atmospheres, etc, and continuously
maintains an accurate count of authorized entrance, so you may
have one attendant for several entrance in the confined space,
you should be able to keep a constant
accurate count, count of them through visual connection or
verbal communication with them while they are in the confined
space.
The attendant has to remain outside the permit space during
entry, until relieved by others, because again, if they enter the
confined space, they become an entrant and not an attendant, and
they lose that capability of warning others about hazardous
atmosphere or environment inside that confined space.
Communicates with authorized entrance as necessary to to
monitor entrance status. So again, keeping a conversation with them
to make sure that they are still alert and everything and monitors
activities inside and outside space. So if there's something
that's going to block the entrance, for example, or the exit
from that confined space they should make, make sure that they
remove that obstacle, to make it clear for the entrance to be able
to get out if they need to
other duties,
order the entrant to exit if the attendant detects a prohibited
condition, or the attendant detects a behavior change in the
authorized entrant. They are not fully alert. Attendant detects a
situation out outside that could endanger the entrance. So again,
if there's a vehicle, for example, that's gonna come close by that
may block the the exit route for the entrance and the attendant can
can. Or if the attendant cannot perform his or her duties, if they
need to be on if they go to the restroom, for example, or
whatever, then if they cannot keep that constant communication and
contact with the entrance, they have to call for someone else to
take their place. Or if there's no one else to take their place, then
they have to order the entrance to exit until they find the
replacement for that attendant.
In case someone, some of the entrants are not feeling fine, or
there's a problem inside the confined space and they cannot get
out on their own, then the attendant is going to summon
rescue as soon as possible, whenever necessary. Warn the
authorized persons to stay clear the unauthorized warn the
unauthorized persons who are not supposed to be close to the
confined state, to stay clear to to make it easier to extract the
ones who are inside, if they need to be extracted, alert entrance,
if unauthorized persons enter and perform non entry rescues as
needed. So as we said before, they can perform rescue as long as they
do not get inside the confines phase and perform no duties that
might interfere with the attendance primary duties. So when
they are an attendant, that's all they do. They're not doing
anything else to keep full attention on those who are inside
the confined space,
the third position is the entry supervisor, and that's an even
higher position. So we have we talked about the entrant, we
talked about the attendant, and the third one is the entry
supervisor. The entry supervisor determines if entry conditions are
acceptable, oversees the entry operations, the whole schedule,
the whole scenario of the operation, and terminates entry as
required. If there's any condition that makes work inside the
confined space hazardous, they would terminate the entry an entry
supervisor may also serve as an attendant or as an authorized
entrant. So there can be a dual role in this case, but if they're
going to act as an attendant, then that's all they can do. They do
not do any other positions. So the attendant will have the authority
of the entry supervisor. And if there's an authorized, authorized
entrant that has this power to end the entry whenever needed. Then
again, they can assume that responsibility.
The duties of the entry supervisors, very similar to the
previous ones, know the hazardous, the hazards regarding the space,
verifies that the permits completed are completed properly.
All tests required for the permit are completed and all procedure
and equipment are in place before endorsing the permit and allowing
entry to begin
and terminates the entry and cancels the permit as required if
any of these conditions are violated,
verifies rescue services are available. That's that should be
before the entry removes unauthorized people from the area
and determines whenever responsibility for a permit is
transferred, that entry operations remain consistent, consistent with
the terms of the entry permit that were issued in the first place. So
yeah, another definition is about hot work permit. What kind of work
is going to be considered as hot work? The employees written
authorization to perform operations capable of providing a
source of ignition. So if there's going to be something causing a
spark, for example, whether it's grinding or welding or any other
operation that's going to result in some sparks that can cause
ignition, then it's going to be considered a hot work environment
that requires a hot work permit.
Engulfing is the capture of a person by liquid or finely divided
or flowable, like a powder, solid.
Substance that could smother or crush a person. So if someone's
working inside a silo, for example, a grain silo being
engulfed by the grains, that's a that can smother by deprivation of
oxygen or crush due to the pressure of that huge amount of
grains, it can kill a person.
Entry is when a person passes through an opening into a permit
required confined space. The entry includes the ensuing work
activities in that space.
Entry permit, or just permit, in this case, is a document provided
by the employer to control the entry into permit space.
A permit required confined space. Is a confined space as we
described it before. A program means for controlling the entry
into the confined space and for protecting employees from the
hazards so we need. The ultimate goal is to protect the employees
who are working inside that confined space,
as we mentioned before. Oxygen deficient atmosphere is an
atmosphere with less than 19 and a half percent oxygen by volume.
Oxygen enriched atmosphere is an atmosphere with more than 23 and a
half percent oxygen by volume. You should remember these two numbers.
Hazardous atmosphere is one that may cause employees to be injured,
killed, incapacitated, or impaired again, through lack of oxygen or
something like that, from one or more of the following causes.
First, flammable gas, vapor or mist, in excess of 10% of its
lower flammable limit. When we talk about a flammable gas or
vapor or mist, it can only ignite within a certain range. The bottom
line of that range is called the lower flammable limit, below which
it's too lean to ignite and the upper
flammable limit beyond which it's too rich to ignite so it does not,
does not have enough oxygen or enough air to help with the
ignition, but anywhere in between the LFL and the UFL, the lower
flammable limit and The upper flammable limit. This is a
dangerous situation.
Another condition here is
that causes a hazardous atmosphere is combustible dust at a
concentration that meets or exceeds its LFL. Again, if it's at
the lower flammable limit or more, that's dangerous.
Oxygen concentrations below 19 and a half or above 23 and a half,
and any other dangerous atmospheric condition like carbon
monoxide or
H 2s you
so what is got? What kind of information is going to be
included on the entry permit? And this is going to be found under
1910, one of 140, 6f,
in the code book the permit is going to identify the permit space
to be entered. The purpose of the entry, date and duration of the
entry, for how long people can work on the inside, identification
of the authorized entrance. Who are they by name, identification
of the attendance again, who are they by name,
identification and of and signature of the supervisor, the
entry supervisor, who, as we mentioned before, could be either
an entrant or an attendant. Hazards of the permit space to be
entered, whether it's going to be
poisonous gasses or nauseous gasses, or lack of oxygen or
flammable mist or vapor, or whatever controlled measures taken
to isolate hazard what kind of protective equipment, for example,
acceptable entry conditions, whether it's going to be during
the day or at night or things like that, results of initial and
periodic atmospheric monitoring. So we're going to keep monitoring
the atmosphere to make sure that the conditions do not change, thus
it necessitating someone to get outside, or the use of additional
protective equipment and rescue and emergency services available
if someone is hurt on the inside, how can we extract them, and what
kind of medical attention are they going to need?
Communication procedures between attendance and entrance, whether
it's going to be just voice or visual contact, or what other kind
of contact equipment, PPE, alarm system, etc. PPE stands for person
protective equipment, of course, alarm system etc, required for
entry and rescue operations and any other necessary information
and other required permits, like if it's going to be considered a
hot.