Printing Press classification

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bgtronics

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Hi. I need to know what is a size of class1 div.1 area for industrial newspaper printing press. I have to install an equipment, wit the non explosion proof controller, witch has a cable of only 30'
 

eric7379

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Location
IL
Unless this is a gravure process (which I highly doubt because I have never seen/heard of a gravure newspaper press, but I may be wrong though!) how do you know that it is class 1, division 1?

Do you work for the printing company, or are you just installing equipment on/around the press? Is the entire press classified as class 1, division 1, or just certain areas of the press? If the entire press is class 1, division 1, you should consult with the company to find out where the boundary starts/ends, or if it is just a certain area of the press and where that boundary starts/ends. Maybe, to play it safe, they classified the entire pressroom as class 1, division 1?

Just off the top of my head, I can't think of an area around a press that would be class 1, division 1, unless it is a dedicated "room" where all of the solvents (blanket wash) are stored. The inks used on newspaper presses are typically soy based. The blanket wash that is typically used is somewhat flammable. The etch/fountain solution is non-flammable. There are lots of different chemicals that are used in the printing process.
 

rbalex

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Unless this is a gravure process (which I highly doubt because I have never seen/heard of a gravure newspaper press, but I may be wrong though!) how do you know that it is class 1, division 1?

Do you work for the printing company, or are you just installing equipment on/around the press? Is the entire press classified as class 1, division 1, or just certain areas of the press? If the entire press is class 1, division 1, you should consult with the company to find out where the boundary starts/ends, or if it is just a certain area of the press and where that boundary starts/ends. Maybe, to play it safe, they classified the entire pressroom as class 1, division 1?

Just off the top of my head, I can't think of an area around a press that would be class 1, division 1, unless it is a dedicated "room" where all of the solvents (blanket wash) are stored. The inks used on newspaper presses are typically soy based. The blanket wash that is typically used is somewhat flammable. The etch/fountain solution is non-flammable. There are lots of different chemicals that are used in the printing process.
Eric,

I'm extremely grateful you tackled this question. I?ve been trying to research it but just haven?t had the time without a bit more understanding of the overall process; i.e., knowing what else to look for.

In any case, I heartily endorse your response with one added comment: if there is a Division 1 there must also be a Division 2 unless the entire process is enclosed in un‑pierced enclosure. [500.5(A)(2)(3)]
 

sgunsel

Senior Member
There is no simple answer. Check out NFPA 34, which applies to printing operations as well as other finishing processes. Mostly depends on the presence of flammable liquids, including inks, other finishes, thinning agents, and cleaning materials. You may also have combustible residues from coating materials and combustible dusts from paper or other substrate.
 

rbalex

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There is no simple answer. Check out NFPA 34, which applies to printing operations as well as other finishing processes. Mostly depends on the presence of flammable liquids, including inks, other finishes, thinning agents, and cleaning materials. You may also have combustible residues from coating materials and combustible dusts from paper or other substrate.
sgunsel,

Thanks for your response too.

I'm pretty familiar with NFPA 34 and have never heard of it applying to printing processes. That's not to say it doesn't, but it doesn't seem to fall within the Scope statement (1.2) unless you consider it a roll coating process, but that doesn't seem consistent with the general process concept outlined in 9.7.1(3).

In any case, I'm grateful for your insight.

Obviously, if sufficient volatile material is involved, electrical area classification is warranted and subject to NFPA 30 among others. NFPA 30 has a broad Scope (1.1.1) and deals with a general and wide array of processes.

I still endorse Eric's response and suggest getting the manufacturer's input.

Edit Add: Remember the electrical area classification must be documented; hopefully by someone qualified to make the evaluations. [500.4(A)]
 
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sgunsel

Senior Member
rbalex,

NFPA 34 has always been considered applicable to printing. As you mentioned, printing is similar to roll coating. The next version will make this explicit.
 

rbalex

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... The next version will make this explicit.
sgunsel, thanks once again for pointing me in that direction.

After your last post I looked up the ROP for the next edition of NFPA 34. It looks like the Technical Committee on Finishing Processes (TC) has taken it upon itself to make the document’s application to printing “explicit.” Of the 44 total Proposals, only one appears to have been made by an entity other than the TC itself. Basically, the TC rewrote the document on their own.

It also appears from Mr Haynack's abstention notes that several Printing Associations are opposed to the inclusion; I doubt the debate is over.

I can already see a lack of understanding of electrical area classification principles on the TC's part. It’s moderately surprising since the UL Alternate is also an Alternate member of both CMP 14 and the NFPA 497 TC. But it’s only moderately surprising since he deals primarily with the equipment (and in all fairness, he does it very well) and not the actual process of electrical area classification.
NOTE: Underline indicates new text; Red indicates deleted text.

34-21 Log #CP24 Final Action: Accept (6.2.2)
_______________________________________________________________
Submitter: Technical Committee on Finishing Processes,
Recommendation: Revise to read:
Open flames, spark-producing equipment or processes, and equipment whose exposed surfaces exceed the autoignition temperature of the flammable or combustible dipping or coating liquid being used shall not be located in the dipping or coating process area or in surrounding areas that are classified as Division 2 or Zone 2.
Substantiation: Only flammable and combustible liquids are intended to be covered by this requirement and the requirement applies to all processes within the scope of the standard.
Committee Meeting Action: Accept
Number Eligible to Vote: 27 Ballot Results: Affirmative: 22 Abstain: 1
Ballot Not Returned: 4 Jurasic, J., Korecky, M., McKnight, J., Murin, G.
Explanation of Abstention: HAYNACK, B.: See my Explanation of Abstention on Proposal 34-2 (Log #CP2).
_______________________________________________________________

34-23 Log #CP26 Final Action: Accept (6.4.2)
_______________________________________________________________
Submitter: Technical Committee on Finishing Processes,
Recommendation: Revise to read: Electrical wiring and electrical utilization equipment located within 1525 mm (5 ft) of a vapor source shall be suitable for Class I, Division 1 or Class I, Zone 1 locations. The space area inside a the dip tank, ink fountain, ink reservoir, or ink tank shall be classified as Class I, Division 1 or Class I, Zone 0, whichever is applicable.
Substantiation: Added text correlates with expansion of the standard to cover printing processes.
Committee Meeting Action: Accept
Number Eligible to Vote: 27
Ballot Results: Affirmative: 22 Abstain: 1
Ballot Not Returned: 4 Jurasic, J., Korecky, M., McKnight, J., Murin, G.
Explanation of Abstention: HAYNACK, B.: See my Explanation of Abstention on Proposal 34-2 (Log #CP2).
_____________________________
Proposal 34-21 Electrical area classification should NEVER be used for anything other than the selection of electrical equipment and installations.
Proposal 34-23 If they are going to specify a Division 1 or Zone 1 hazard radius from a potential source they are obligated by NFPA 70, Section 500.5(B)(2)(3) to define a Division 2 or Zone 2 radius as well.
 

eric7379

Member
Location
IL
I can certainly understand why printing associations would be opposed to this rule, at least with the language in which it is written, in my opinion. To just use the blanket term of "ink fountain" is entirely incorrect. Almost every single printing press in existence has an ink fountain. I am speaking about web offset printing presses.
However, that is where the similiarities stop. Every press is different. Different inks are used, depending on the application. Inks used in gravure printing are highly flammable. Inks used in newspaper printing are not flammable. Yes, some of the solvents that are used are flammable. Some of the solvents that are used have such a low VOC content that when a LEL test was being performed once on a dryer during commissioning that the concentration went down when an automatic blanket wash was done.

What will happen when a press no longer has an ink fountain?

http://www.gossinternational.com/cl...t_PDFs/LSE_DigiRail_and_Slow_Inker_DUR_EN.pdf

The above named system is catching on within the industry, and with the system, an ink fountain is not used. It is not a revervoir or a tank either. It feeds ink directly onto the rollers.

I certainly understand the intent of the change in the rule. I just think that it needs to be broken down further than what it is.
 

sgunsel

Senior Member
An area where a sufficient fire hazard exists to warrant special consideration for electrical equipment and wiring would also require control of open flames and other ignition sources.
 

rbalex

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An area where a sufficient fire hazard exists to warrant special consideration for electrical equipment and wiring would also require control of open flames and other ignition sources.
Possibly - but that just ain't the purpose of electrical area classification. See the basic Scope statement for the fundamental NFPA document on electrical area classification:
NFPA 497 Recommended Practice for the Classification of Flammable Liquids, Gases, or Vapors and of Hazardous (Classified) Locations for Electrical Installations in Chemical Process Areas:
...

1.1.2
This recommended practice provides information on specific flammable gases and vapors, flammable liquids, and combustible liquids, whose relevant combustion properties have been sufficiently identified to allow their classification into the groups established by NFPA 70, National Electrical Code? (NEC?), for proper selection of electrical equipment in hazardous (classified) locations. The tables of selected combustible materials contained in this document are not intended to be all-inclusive.

...

[RBA Note: underlines mine]
In my experience, whenever electrical area classification is used for any purpose other than selecting electrical equipment - it screws things up from unintended consequences.
 
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rbalex

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An area where a sufficient fire hazard exists to warrant special consideration for electrical equipment and wiring would also require control of open flames and other ignition sources.
Oh, Come on!! Someone hasn't jumped in and noted that "...open flames and other ignition sources" render a location unclassified in the first place?
 

sgunsel

Senior Member
The extent of classified areas depends on the fire hazards that may be present. If flammable vapors, only one possibility of several, are present then there are several guidelines in various NFPA standards to help make that determination. Once a significant fire hazard is established, precautions are necessary to prevent ignition. Electrical sparks and arcs from the electrical power distribution and usage system are not the only potential (!) sources of ignition. Ignition sources need not be permanent. Many fires are started by the use of portable welding and cutting torches or grinding equipment during repairs or modifications in a classified area without making the area safe. Electrical wiring is not the only possible source of high temperatures. Please remember that "NFPA" is the National Fire Protection Association, the NEC is only one of hundreds of NFPA standards.
 

rbalex

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The extent of classified areas depends on the fire hazards that may be present. If flammable vapors, only one possibility of several, are present then there are several guidelines in various NFPA standards to help make that determination. Once a significant fire hazard is established, precautions are necessary to prevent ignition. Electrical sparks and arcs from the electrical power distribution and usage system are not the only potential (!) sources of ignition. Ignition sources need not be permanent. Many fires are started by the use of portable welding and cutting torches or grinding equipment during repairs or modifications in a classified area without making the area safe. Electrical wiring is not the only possible source of high temperatures. Please remember that "NFPA" is the National Fire Protection Association, the NEC is only one of hundreds of NFPA standards.
Your first statement is simply incorrect. The extent of a classified location is based on the "fuel" side of the fire triangle; i.e., flammable materials and the environment’s effects, including geometry, air flows, ambient temperature, etc. on the flammability of the material – but not the ignition. Ignition sources are a separate side of the fire triangle. The third side is generally oxygen.

Since area classification “… in accordance with … NFPA 70, National Electrical Code” is specifically mentioned in NFPA 34, Sections 6.3.1 and 6.3.2 and there is nothing in any other Proposal that would differentiate NFPA 34 uses of “Divisions” and “Zones” it must be concluded that they are improperly used in Proposals 34-21 and 34-23. And as I mentioned in my previous post, other sources of ignition that are regularly used in a location are the basis for making a location “unclassified” in electrical area classification applications. [NFPA 497 Section 5.4 in general and 5.4.3 specifically] NFPA 497 is the most general NFPA document on classifying materials and determining the area classification of locations. I’ve noted many time’s before, that a “hot-work” permit temporarily “reclassifies” a location per NEC Section 500.4(A)(1).

Since Proposal 34-21 specifically defines a Division 1 or Zone 1 envelope around a source (which is fine by the way) they also need to define a Division 2 or Zone 2 envelope. Still not knowing the processes involved, I suspect the tanks and reservoirs are basically enclosed and Division 1 or Zone 0 is probably correct. I have no idea what a “fountain” is.

As a general aside all NFPA documents that refer to Class and Division or Zone area classification ultimately are referencing NFPA 70, the NEC.

Having classified locations for well over 40 years in myriads of applications (petrochemical, chemical, mining, pulp&paper, wastewater, etc) I am well aware there are other considerations – but none that you raised with respect to Class, Division or Zones. Nevertheless, this was one reason I sincerely appreciated both your and eric’s responses – I still don’t know it all and hope to continue learning. Rest assured, I intend to comment on these Proposals to assist the TC is developing a proper set of rules. I’ll let the Printing Associations raise objections to the overall changes, if necessary.
 

gadfly56

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Location
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Professional Engineer, Fire & Life Safety
Not to mention static electricity and resulting discharges that are always present in high speed printing.

Heck, even our engineering plotter has a "tinsel string" across the front to drain away the static charge, and it's about as far from high-speed as you can get!
 

sgunsel

Senior Member
Rbalex, sounds to me like we agree for the most part. My "first" statement is not any different from yours. If a fuel (vapor, gas, or solid) is present in a combustible concentration, we have a fire hazard. Oxygen will be present except in a controlled atmosphere.

Controlling all ignition sources is essential to preventing fire. Static electricity and all other ignition sources must also be addressed in classified areas. The hazard remains long after the electrician leaves. Static electricity discharges can clearly cause ignition.

I agree that if the hazard is removed, the classification changes.
 

rbalex

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Rbalex, sounds to me like we agree for the most part. My "first" statement is not any different from yours. If a fuel (vapor, gas, or solid) is present in a combustible concentration, we have a fire hazard. Oxygen will be present except in a controlled atmosphere.

Controlling all ignition sources is essential to preventing fire. Static electricity and all other ignition sources must also be addressed in classified areas. The hazard remains long after the electrician leaves. Static electricity discharges can clearly cause ignition.

I agree that if the hazard is removed, the classification changes.
We?re almost together on this; but let me explain why I cited NFPA 497, 5.4.3:

5.4 Unclassified Locations
?
5.4.3 Open flames and hot surfaces associated with the operation of certain equipment, such as boilers and fired heaters, provide inherent thermal ignition sources. Electrical classification is not appropriate in the immediate vicinity of these facilities. However, it is prudent to avoid installing electrical equipment that could be a primary ignition source for potential leak sources in pumps, valves, and so forth, or in waste product and fuel feed lines.
?
Within the common context of the fire triangle when all three sides are immediately or commonly present and the ?ignition? side is not an electrical source, the general principals of electrical classification would not classify the immediate location. The revised NFPA 34 uses electrical classification improperly. This is not to say the danger isn?t there or that precautions are improper, simply that the way they are being defined is.

I noticed I can?t comment on NFPA 34 this time around since the cut-off date was last September. The ROC indicates they have covered one of my objections though; they defined the Division 2 envelopes. However, they now erroneously called for motors to be listed. For Class I, Division 2 and Zone 2, there is no such listing unless they go all the way to Division 1 motors. (I may object to it as ?new material? though)
 

rbalex

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Sorry, we got carried away.

Sorry, we got carried away.

Thanks. For couple of days I?m reading your comments, and, nothing!

Where is the answer?
The attached, graphic appears to be what will be included in the next NFPA 34 Edition. I don't know how (or if) it applies to your installation. It does follow fairly common principals:
  1. A source will have a 5' Division 1 envelope above and horizonal to it.
  2. The Division 1 envelope continues to grade from any extreme horizonal measurement from a source
  3. Beyond the Division 1 envelope is an additional 3' Division 2 envelope in all directions to any non-pierced barrier.
  4. The Division 2 envelope extends an additional 20' beyond the extreme Division 1 envelope and 3' above grade.
The diagram will probably not show up in the NEC until 2014, if ever. I reiterate that you should contact the manufacturer to identify the "sources" or have someone qualified to make the judgment.
 
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