Classified Receptacle

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rbalex

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In the interest of full disclosure, I don't have access to the latest API RP-500. But the 2002 edition doesn't consider the area inside the dike Division 1. See Figure 7.
 

don_resqcapt19

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Don -
I think you are stuck in fire-fighter mode. And I highly suspect you don't do work in these areas.

My first questions are:
Q1: What danger of fire?
Q2: What danger of inhalation hazard?

The area is sniffed clear and monitored - remember?

Here is an example: Cutting and welding inside of a tank yard - products with a flashpoint less than 100F. Yes, people actually do this stuff. I picked this one because it's somethng I did in a previous life - so it is not contrived.

Inside the tankyard, below the berm is DIV 1 - as I recall (API RP 500) Now, how do you suspose that one does this with a 1,000,000 gallons of Av-gas or Jet-B staring at you over your shoulder. The ppe consists of treated cotton fire resistant coveralls. Nomex gets ate up from the welding splatter - its useless. There are no escape bottles, or in-use SCBA - that's riduculus. Provided you bothered to read my posts, you already know how one does this safely - with a couple of extras:
Isolate and clean up the piping.
No tank loading while work is on-going - don't want any venting
Post a fire watch - with an extinguisher or two, and a shovel

Now that you are working up a good case of indignant righteousness - I have a couple of questions:
Q3: This ppe that you insist is needed for work in a C1D1 area (non-confined space), just what standard are you using to select the protection level?

Q4: Once a day the company sends the yardman to record the mechanical level gauges. Do you expect her to wear the same gear as the welded plumbers?

ice
I know what is done and that it is typically safely done, and I work in a plastics manufacturing plant every day, but the plant has very few Division 1 areas.
I just cannot justify putting anyone in a Division 1 area without the PPE that would be required for the product that required the classification. You cannot on one hand tell someone that under normal conditions that you can have a concentration at or above LEL and at the same time tell him to enter the area without protection from that product. I could even see the EPA looking at areas that are classified as Division 1 and saying...wait a minute...we have an emissions issue here.

I guess maybe my real point is that very few Class I, Division 1 areas are really that.

Also I misspoke when I used STEL in my previous comment... I should have used IDLH. This NIOSH document lists the IDLH levels for number of products. If the IDLH value has (LEL) after the value then the IDLH level has been set at 10% the LEL even if that concentration is not IDLH.
 

don_resqcapt19

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Don -
...
Q1: What danger of fire?
The classification tells me that we can be at or above LEL under normal operating conditions.
Q2: What danger of inhalation hazard?
See previous answer.

The area is sniffed clear and monitored - remember?
What level do you activate your flammable gas alarm at? Many set the meter alarm at 10% of LEL, but for a number of products you are already above IDLH at 10% of LEL.
Do you use a flammable gas detector that is specific for the product involved, or the generic one where you have to use a factor for the meter reading to get the percent of LEL for the actual product?
Here is an example: Cutting and welding inside of a tank yard - products with a flashpoint less than 100F. Yes, people actually do this stuff. I picked this one because it's something I did in a previous life - so it is not contrived.
Yes I am aware that is a common practice and that there is no practical way to avoid doing that, but if it is really a division 1 area, I don't think that type of work should be permitted.

...Q3: This ppe that you insist is needed for work in a C1D1 area (non-confined space), just what standard are you using to select the protection level?
It would have to be based on what protection is required for the product at a concentration at or above

Q4: Once a day the company sends the yardman to record the mechanical level gauges. Do you expect her to wear the same gear as the welded plumbers?
Other than the PPE that is specific for the welding task, yes the same level of PPE is required.
 

iceworm

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Yes I am aware that is a common practice and that there is no practical way to avoid doing that, but if it is really a division 1 area, I don't think that type of work should be permitted. ....
I see a disconnect between our two viewpoints.

I think when you say "Div 1", you mean, "a significant concentration of flammable vapor exists all the time". My translation of your posts essentially reflect work in the interior vapor space of a tank. And, no, one does not do that while the tank has flammable liquid in it. So the practice is to empty the tank, isolate, ventilate, clean. Then enter the tank for the work, The only practices and ppe are for confined space - not for D1 areas

When I say "Div 1", I mean, "a significant concentration of flammable vapor exists more often than 1 hour in 8000 hours" That leaves a lot of time the area is clear. One drains, isolates, cleans, ventilates. And since one might choose to not have all the equipment in the area locked out, post a fire watch and gas monitor.

rbalex - I did not look up the number of hours to diferentiate between D1 and D2. Please correct if available.

Concerning gas detectors: One uses the type required for the job conditions. One gets the equipment required for the job. No different than any other vocation. Can they be hard to use or complicated? (complicated defined for this purpose as, "more than one button") Can be. So what? Welded plumbing in classified areas is specialized work. Electrical maintenance is classified areas is specialized work. One doesn't send out shoe clerks - one sends out trained techs.

I would agree...having an escape bottle would not be good enough...in my opinion, if you are in a Class I Division 1 area you need to be using PPE suitable for the hazard...not just have it available. In the case of flammable products that may also require PPE to protect you from fire as well as inhalation hazards.

QUOTE=don_resqcapt19;1491744] ... It would have to be based on what protection is required for the product at a concentration at or above ....[/QUOTE]

I'm stuck - I'm still asking: I know how to pick out ppe for arc-flash. I can pick out respiratory protection for hazardous atmospheres. So how do I pick out ppe clothing to walk through a Div 1 area like a pumphouse that won't have a hazardous atmosphere unless there is a seal leak? What document or standard do you reference?

ice
 

don_resqcapt19

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When I say "Div 1", I mean, "a significant concentration of flammable vapor exists more often than 1 hour in 8000 hours" That leaves a lot of time the area is clear. One drains, isolates, cleans, ventilates. And since one might choose to not have all the equipment in the area locked out, post a fire watch and gas monitor. ...
To me Division 1 means the flammable concentration can exist under normal operating conditions. Yes a lot of the time it is clear, but how fast can it change, how fast does the meter react, how fast can you run?

Concerning gas detectors: One uses the type required for the job conditions. One gets the equipment required for the job. No different than any other vocation. Can they be hard to use or complicated? (complicated defined for this purpose as, "more than one button") Can be. So what? Welded plumbing in classified areas is specialized work. Electrical maintenance is classified areas is specialized work. One doesn't send out shoe clerks - one sends out trained techs.
I know that where I am at the combusible gas detectors are not gas specific and that they alarm at 10% of LEL, but I also know that for many of the products here 10% of LEL is way above IDLH. They are calibrated for either propane or pentane, not sure which one, and those are not the flammable products that are used here. In there defense any hot work is shut down if there is any reading on the combustible gas detector, but you don't know that there is a reading unless you are looking at the display. The Division 1 areas are very limited at this plant and so it would be rare to be in such an area.
I'm stuck - I'm still asking: I know how to pick out ppe for arc-flash. I can pick out respiratory protection for hazardous atmospheres. So how do I pick out ppe clothing to walk through a Div 1 area like a pumphouse that won't have a hazardous atmosphere unless there is a seal leak? What document or standard do you reference?
ice
That is a good point. I forgot about the actual fire issue and was just thinking about the respiratory issue. I guess, I have to say that you cannot enter a Division 1 area. The only document is the definition of Division 1 and it says that a flammable concentration may exist under normal operating conditions. Based on that I don't see how an employeer can send an employee into the Division 1 area.

I understand that I am being unreasonable here, but I just don't like how the system works...
 

rbalex

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...
When I say "Div 1", I mean, "a significant concentration of flammable vapor exists more often than 1 hour in 8000 hours" That leaves a lot of time the area is clear. One drains, isolates, cleans, ventilates. And since one might choose to not have all the equipment in the area locked out, post a fire watch and gas monitor.

rbalex - I did not look up the number of hours to diferentiate between D1 and D2. Please correct if available.
?

The number of hours per year is neither an NFPA/NEC nor API concept; it is an IEC concept. You will note that it isn?t mentioned in either Section 500.5(B)(1), or Section 505.5(B)(1) or (2) - even in the FPN/INs. Unless it was snuck in in the latest API RP-505 [2011] it isn?t there either. If it is, it still isn't an NFPA/NEC concept.

When it was first proposed for RP-505 I kept it out because it is one of the fundamental differences between US domestic Divisions/Zones and IEC Zones. US Divisions/Zones are defined in terms of possibility; i.e., it could happen under the specified circumstances; i.e. under ?normal? or certain ?abnormal? operating conditions. The problem is normal is undefined. If I really needed to, I can show you Division 1 locations that are never hazardous in their ?normal? operating lifetimes. As an interesting aside, look up 500.8(B)(5) as ?normal? is applied to motors. (Technically, you can't start a motor in a classified location)

IEC Zones are defined in terms of probability ? that?s where the hours per year come in and even then they vary from jurisdiction to jurisdiction. Assuming a year is roughly 8000 hours, the most common is 1000 hrs/yr or more is Zone 0; 100 hrs/yr or more is Zone 1; 10 hrs/yr (or 1 depending on the jurisdiction) is Zone 2. A few (very few) IEC jurisdictions will say any probability is Zone 2, but that is rare.
 

iceworm

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I'm a little short on time - so my responses will be a bit brief.
In the interest of full disclosure, I don't have access to the latest API RP-500. But the 2002 edition doesn't consider the area inside the dike Division 1. See Figure 7.
Okay, I pulled my copy of API RP 500, 3rd edition, Dec 2012.

You are correct. Both Section 8.2, Fig 6, fixed roof, and Fig 7, floating roof, show the area inside the dike as D2. Read Note 1 about high filling rates and blending operations "may require extending the boundries of classified areas". Most of my clients treat the areas inside the dike as D1 for maintenance activities. Some show on the area classification drawings as D1, some do not.

The number of hours per year is neither an NFPA/NEC nor API concept; it is an IEC concept. You will note that it isn?t mentioned in either Section 500.5(B)(1), or Section 505.5(B)(1) or (2) - even in the FPN/INs. Unless it was snuck in in the latest API RP-505 [2011] it isn?t there either. If it is, it still isn't an NFPA/NEC concept.

When it was first proposed for RP-505 I kept it out because it is one of the fundamental differences between US domestic Divisions/Zones and IEC Zones. US Divisions/Zones are defined in terms of possibility; i.e., it could happen under the specified circumstances; i.e. under ?normal? or certain ?abnormal? operating conditions. The problem is normal is undefined. If I really needed to, I can show you Division 1 locations that are never hazardous in their ?normal? operating lifetimes. As an interesting aside, look up 500.8(B)(5) as ?normal? is applied to motors. (Technically, you can't start a motor in a classified location)

IEC Zones are defined in terms of probability ? that?s where the hours per year come in and even then they vary from jurisdiction to jurisdiction. Assuming a year is roughly 8000 hours, the most common is 1000 hrs/yr or more is Zone 0; 100 hrs/yr or more is Zone 1; 10 hrs/yr (or 1 depending on the jurisdiction) is Zone 2. A few (very few) IEC jurisdictions will say any probability is Zone 2, but that is rare.

I misquoted the concept of 1 hour in 8000.
6.2.3.2 Petroleum handling equipment does not fail frequently. Furthermore, the NEC requirements for electrical installations in Division 2 locations allow that a source of ignition may occur in the event of an electrical equipment failure. This also does not happen frequently. For example, assume that the electrical and petroleum handling equipment each fail at the rate of once every 8,000 hours (once per year). The probability that both types of equipment will fail during
the same hour is only one in 64 million. These assumed failure rates are deliberately high and the failures usually would occur during a time interval shorter than one hour. On a realistic basis, the probability of simultaneous failure is very remote; therefore, this consideration often justifies a Division 2 (versus Division 1) classification.​
The concept applies to considering simultaneous failures releasing flammable concentrations of vapor and and electrical failure providing ignition. Of course, when one is performing maintenance in an area with possible flammable vapor emmission, the ignition source is already there - the maintenance work.

ice
 

iceworm

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To me Division 1 means the flammable concentration can exist under normal operating conditions.
The key is "normal"
3.2.10.2 Class I, Division 1 location: A location in which ignitible concentrations of flammable gases or vapors are expected to exist under normal operating conditions or in which faulty operation of equipment or processes might simultaneously release flammable gases or vapors and also cause failure of electrical equipment. Reference Section 6.2.1 .l.a and NEC Article 500-5(a) for a more complete definition​
Area Classification is about electrical installations - not maintenance. However, one perhaps should consider the Area Classification as a guide when doing maintenance. Again the key is 'normal". All of my examples include (or should have included :)dunce: if I didn't) isolate, drain, clean, ventilate, monitor. Ah, (you say) but that is no longer D1. Well, no one is going to temporarly redline the area classification drawing. Consider the prework similar to energy isolation for electrical maintenance.

My new translation of your comments leads me to believe we are not at cross purposes. You are correct, no one should be going into a "normal" D1 area to do maintenance. My response is, "You're right. Clean up, isolate and ... Shutting down (lockout) tanking loading to prevent reliefs is usual. The area is still D1 because area classification is about electrical installations - not maintenance.

To me Division 1 means the flammable concentration can exist under normal operating conditions. Yes a lot of the time it is clear, but how fast can it change, how fast does the meter react, how fast can you run? ...
Yes, occasionally things do head for the toilet. You never run - well, unless the fire is licking at one's rear.:blink::sick: Set down the tools. Walk quickly out. Hit the stop switch on the welding machine, which hopefully is on top of the dike, or the other side of the dike.

... The only document is the definition of Division 1 and it says that a flammable concentration may exist under normal operating conditions. Based on that I don't see how an employeer can send an employee into the Division 1 area. ...
In the case where flammable vapors are there all the time - you're right. However, in the example of the tankyard operator gathering readings: She verifies no tank loading, takes a monitor, verifies clear, walks in and gets the readings.

...I understand that I am being unreasonable here, ...
I'm okay with that as long as you aren't the one with the gun and the badge.

...I just don't like how the system works...
Fortunatly for me, the crews I've been around knew how to do the work safely regardless of the system.

ice
 

don_resqcapt19

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...Area Classification is about electrical installations - not maintenance. However, one perhaps should consider the Area Classification as a guide when doing maintenance. Again the key is 'normal".
That is part of my issue. Yes I am aware that the purpose of the area classification is electrical, but once it is classified it is telling me that there is a hazard and that hazard applies to everything.
All of my examples include (or should have included :)dunce: if I didn't) isolate, drain, clean, ventilate, monitor. Ah, (you say) but that is no longer D1. Well, no one is going to temporarly redline the area classification drawing. Consider the prework similar to energy isolation for electrical maintenance.My new translation of your comments leads me to believe we are not at cross purposes. You are correct, no one should be going into a "normal" D1 area to do maintenance. My response is, "You're right. Clean up, isolate and ... Shutting down (lockout) tanking loading to prevent reliefs is usual. The area is still D1 because area classification is about electrical installations - not maintenance. ...
That was not clear and while you have not changed the classification on paper, it has been changed. I am aware of work being done in an area where only the specific equipment was "made safe" and the was other equipment in the area that was not made safe...they were still working in a real division 1 location.


Yes, occasionally things do head for the toilet. You never run - well, unless the fire is licking at one's rear.:blink::sick: Set down the tools. Walk quickly out. Hit the stop switch on the welding machine, which hopefully is on top of the dike, or the other side of the dike.

In the case where flammable vapors are there all the time - you're right. However, in the example of the tankyard operator gathering readings: She verifies no tank loading, takes a monitor, verifies clear, walks in and gets the readings.
I would not permit that entry into the Division 1 area.


m okay with that as long as you aren't the one with the gun and the badge.
I would shake things up if I was.



Fortunatly for me, the crews I've been around knew how to do the work safely regardless of the system.

ice
The way you have described it, I think they have worked safely, but that is not always the case, not even sure it is the norm.
 

rbalex

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As mentioned, I don’t have access to the latest API RP-500 document [2012] but I’m sure it has a scope statement similar to:
1 Scope
1.1 PURPOSE
1.1.1
The purpose of this recommended practice is to provide guidelines for classifying locations Class I, Division l and Class I, Division 2 at petroleum facilities for the selection and installation of electrical equipment. Basic definitions given in the 1996 edition of NFPA 70, the National Electrical Code (NEC), have been followed in developing this recommended practice. This publication is only a guide and requires the application of sound engineering judgment.

1.1.2 Electrical installations in areas where flammable liquids, gases, or vapors are produced, processed, stored or otherwise handled can be suitably designed if the locations of potential sources of release and accumulation are clearly defined. Once a location has been classified, requirements for electrical equipment and associated wiring should be determined from applicable publications.
Applicable publications may include NFPA 70 (NEC) or API RP 14F. Reference Section 2 for publications for other possible applications.
1.2 SCOPE
1.2.1
This document applies to the classification of locations for both temporarily and permanently installed electrical equipment. It is intended to be applied where there may be a risk of ignition due to the presence of flammable gas or vapor, mixed with air, under normal atmospheric conditions. Normal atmospheric conditions are defined as conditions that vary above and below reference levels of 101.3 kPa (14.7 psia) and 20?C (68?F) provided that the variations have a negligible effect on the explosion properties of the flammable materials.
The following items are beyond the scope of this document:
a. Piping systems used for odorized natural gas used as fuel for cooking, heating, air conditioning, laundry and similar appliances;
b. catastrophes such as well blowouts or process vessel ruptures. Such extreme conditions require emergency measures at the time of occurrence;
c. the suitability of locations for the placement of non-electrical equipment; and
d. classification of locations containing combustible dust, ignitible fibers, or flyings.

A few points:


1. Electrical area classification is “…for classifying locations Class I, Division l and Class I, Division 2 at petroleum facilities for the selection and installation of electrical equipment.” [1.1.1]
2. It is NOT for “…catastrophes such as well blowouts or process vessel ruptures. Such extreme conditions require emergency measures at the time of occurrence …” [1.2.1 b]
3. It is NOT for selecting “…the suitability of locations for the placement of non-electrical equipment.,,” [1.2.1 c]
4. It is NOT for selecting toxic PPE (I know it doesn’t say that specifically, but I guarantee it was never in the SOEE’s discussions) [Corollary to 1.1.1 which limits it to “... the selection and installation of electrical equipment …]

BTW NFPA 497/499 have similar scope statements.

My primary objection is when using electrical area classification for anything other than for the selection and installation of electrical equipment it usually ends up with the “other” affected parties wanting to reclassify locations. I’ve had structural engineers wanting to use it for determining fireproofing, piping/mechanical engineers wanting to use it for the placement of non-electrical equipment; civil engineers wanting to use it for the permissive use of automobile traffic (“OK- If you can just get the process engineers to train the gases and vapors to stop at the curb”); and now Don wants to use it for toxic PPE ;)

Each of the above requires a separate employee hazard or process analysis – you just can’t use the electrical area classification document as a catchall.

BTW NEC Section 500.4(A) requires “proper documentation”; effectively, a hot work permit or confined space permit is a temporary reclassification documentation for the activity involved.
 
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iceworm

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...All of my examples include (or should have included :)dunce: if I didn't) isolate, drain, clean, ventilate, monitor. ...

...That was not clear ....

... Get a meter, check %LEL, ventilate till clear, shut down process if needed. No exceptions. ...

... When I was doing this for a living, one would take a %LEL meter, sniff the area, if clear, go to work, meter stays running right next to the tech. ...

... What one could defend is not putting anyone in harm's way by providing continuous monitoring. The trick is not being able to work while the %LEL is up, but monitoring and not working if the %LEL is up - rather ventilate, clear, then work (if the %LEL is up). ...

... . Provided you bothered to read my posts, you already know how one does this safely - with a couple of extras:
Isolate and clean up the piping.
No tank loading while work is on-going - don't want any venting
Post a fire watch - with an extinguisher or two, and a shovel

... So the practice is to empty the tank, isolate, ventilate, clean. ...

... One drains, isolates, cleans, ventilates. And since one might choose to not have all the equipment in the area locked out, post a fire watch and gas monitor.

Don -
You certainly have a interesting perspective on making a concept clear.

Perhaps you could consider reading posts before replying.

ice
 

don_resqcapt19

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Don -
You certainly have a interesting perspective on making a concept clear.

Perhaps you could consider reading posts before replying.

ice
I have read them and re-read them...the first one that makes it clear to me as how you do things is post 48. Some of the others imply, but do not make it clear to me.
 

iceworm

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...Area Classification is about electrical installations - not maintenance. ...

... 1. Electrical area classification is “…for classifying locations Class I, Division l and Class I, Division 2 at petroleum facilities for the selection and installation of electrical equipment.” [1.1.1] ....

... Yes I am aware that the purpose of the area classification is electrical, but once it is classified it is telling me that there is a hazard and that hazard applies to everything. ....

... My primary objection is when using electrical area classification for anything other than for the selection and installation of electrical equipment it usually ends up with the “other” affected parties wanting to reclassify locations. I’ve had structural engineers wanting to use it for determining fireproofing, piping/mechanical engineers wanting to use it for the placement of non-electrical equipment; civil engineers wanting to use it for the permissive use of automobile traffic (“OK- If you can just get the process engineers to train the gases and vapors to stop at the curb”); and now Don wants to use it for toxic PPE ;) ....

Well, since you know area classification applies to electrical, then you also know it does not apply to everything.

... I would not permit that entry into the Division 1 area.

I would shake things up if I was. ....

These statements are not a reasoned argument. You not liking it makes no difference as to whether the practices are safe. Paraphrasing rb, a separate hazrdous analysis is needed for hazardous atmosphere - area classification is not a catchall.

ice
 

don_resqcapt19

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Well, since you know area classification applies to electrical, then you also know it does not apply to everything.



These statements are not a reasoned argument. You not liking it makes no difference as to whether the practices are safe. Paraphrasing rb, a separate hazrdous analysis is needed for hazardous atmosphere - area classification is not a catchall.

ice
We are not going to agree on these issues, so I see no need for me to comment.
 
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