SDS Sheets

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fifty60

fifty60

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I have encountered some SDS sheets that are pretty good and thorough, and I have also encountered SDS sheets that just seem to navigate to the most extreme protection measures. For example, a liquified petroleum product that has "Only use Explosion Proof Equipment".

It just seems like this is someone wanting to just cover their one selves by recommending the solution that is guaranteed to work.

This is great, but it adds a lot of expense that does not have to be there. That expense can actually take away from doing appropriate thing in other aspects of the installation.

There are other protection methods than Explosion Proof Equipment for Class I Div 1 areas. I have even seen the direction of explosion proof equipment in Class I Div 2 areas.

If an SDS says "use explosion proof equipment", am I still able to use other protection methods allowed by NFPA 70 (2017) and API RP 500? Or am I just stuck using the explosion proof equipment?
 
What do you mean by SDS? Usually when we say SDS here we mean separately distributed system.

Generally speaking you are correct that there are other means of protection from explosion in classified areas other than explosion-proof. However they may not be applicable to certain types of equipment. For instance you could not use intrinsically safe wiring techniques to protect motor power wiring.
 
fifty60 said:
If an SDS says "use explosion proof equipment", am I still able to use other protection methods allowed by NFPA 70 (2017) and API RP 500? Or am I just stuck using the explosion proof equipment?
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You might get different answers if you ask an inspector vs. your lawyer. Point being, it depends who you need to answer to.
 
For some reason the paper is titled an SDS and not MSDS. Is there a significant difference here?

I don't think there needs to be any separation between the lawyer and the inspector...the sheet here says "use explosion proof equipment in Class I Div 1 and use explosion proof equipment on spark generating equipment in Class I Div 2." (from memory, but accurate)

So I would not think that would mean you cannot use purged and pressurized equipment, since a certain purged/pressurized option equipment can reduce the Class I Div 1 to unclassified...

The point of my question is when the SDS for says something like this, should it be followed instead of pursuing different options? There really are not many very good options besides explosion proof in Class I Div 1, but there are other protection methods available. And they way it is worded for Class I Div 2 regarding "spark generating equipment" is kind of open ended...and kind of frustrating.

What I would rather see from an MSDS/SDS for is an explanation of the Hazardous area classification and the standards that were used to come to the conclusions. I don't need them to tell me what protection method to use, but an explanation of the area classification would be great...
 
From FedOSHA's perspective SDS and MSDS are functionally the same thing or have been since 2012. (https://www.osha.gov/Publications/OSHA3514.html) SO - If you want to complain about their content and purpose talk to your Senator or Representative. Complaining here is useless.

As far as, "...am I still able to use other protection methods allowed by NFPA 70 (2017) and API RP 500? Or am I just stuck using the explosion proof equipment?" Sure, you can explosionproof alternatives; however, if an accident should ever occur, failure to observe SDS instructions will essentially leave you without defense - even if it had nothing to do with the accident. (Fed and State OSHAs are peculiar that way)

A few other comments:
  • API RP 500 and NFPA 497 are only recommended practices. However, they are both ANSI sanctioned and enforceable under the various OSHA's general duty clause​ by virtue of being recognized industry safety standards.
  • Explosionproof equipment is often required in Class I, Division 2 by Article 501, Part III beginning with Section 501.100. See the various Sections 501.1xx(B). Often the Division 2 requirements will refer back to the Division 1 requirements. In a few cases the Division 1 and 2 requirements are virtually identical; e.g., Section 501.140.
 
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Thank you for that detailed explanation.

I am struggling with some of the terminology in the SDS: "In Division 2 locations, all spark-producing electricalequipment must be explosion-proof and rated Class 1, Group D"

Is "spark producing" the same as "arc producing"? For example, according to the SDS, would I be able to use hermetically sealed switches for relays? Relays are "arc" producing not "spark" producing......am I correct to differentiate between "arc" and "spark"?

Another MSDS I see says "Use explosion-proof electrical (ventilating, lighting and material handling)". What is exactly meant by "material handling"? Is it only equipment in direct contact with the hazardous material?
 
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fifty60 said:
Thank you for that detailed explanation.

I am struggling with some of the terminology in the SDS: "In Division 2 locations, all spark-producing electricalequipment must be explosion-proof and rated Class 1, Group D"

Is "spark producing" the same as "arc producing"? For example, according to the SDS, would I be able to use hermetically sealed switches for relays? Relays are "arc" producing not "spark" producing......am I correct to differentiate between "arc" and "spark"?

Another MSDS I see says "Use explosion-proof electrical (ventilating, lighting and material handling)". What is exactly meant by "material handling"? Is it only equipment in direct contact with the hazardous material?
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It's mentioned several times elsewhere but the easiest Section to cite is 501.15(A)(1) Where, "The enclosure contains apparatus, such as switches, circuit breakers, fuses, relays, or resistors, that may produce arcs, sparks, or temperatures that exceed 80 percent of the autoignition temperature, in Celsius, of the gas or vapor involved in normal operation." There are similar statements throughout Articles 500 through 503. Other Articles generally back reference to the same. When I teach a class I usually refer to them as arcing, sparking or high temperatures (ASH).

Via Exceptions, Section 501.15(A)(1) then describes potential alternate protection techniques.

With regard to the specific equipment mentioned it is usually best to enquire what is meant from the SDS author or the products manufacturer. Such manufacturers will NOT tell you how to classify a location though; that is left up to those qualified to do so.
 
OK, it seems to me that using a protection method for relays and switches such as IS or hermetically sealed as describe in the exception to 501.15(A) would then make them not fall under the "spark" producing.

It is just kind strange to me how to interpret the method. It seems like they are saying use the EP equipment as the protection method, but if other protection methods are used you can use the other protection method. It just does not explicitly say that. But a hermetically sealed pressure switch would no longer be arc producing....it makes sense, but the wording was a little hard to digest.

One SDS I am looking at give the EP equipment recommendation for Class 1 Div I, and the "arc" producing requirement for Class I Div 2. But the other SDS for a different LPG only says use EP for "lighting, ventilating, and material handeling" equipment.

The second SDS does not mention hazardous area classification. So it seems difficult to use something like Annex D of API RP 500 to set up Div 1 and Div 2 around equipment based off of Mass Release Rate, etc. Using that SDS alone it says if you are using the substance, use EP equipment.
 
From what I am able to find, "material handling" refers to material transportation an not machine process control. Does material handling refer to process control equipment like pressure switches and other instruments involved in a process like filling a vehicle? Or does it only apply to actual transport of the hazardous material?
 
I just cited Section 501.15(A)(1) as an example where the various potential ignition sources were listed together; HOWEVER, the Exceptions only apply as to whether or not the enclosure in question is required to be sealed in Division 1; it is still required to be explosionproof per Section 501.10(A)(3). Section 501.15(B)(1) refers back to 501.15(A)(1) where the enclosure is required to be explosionproof.

I don't know if I can resolve you SDS misgivings. I can only observe that you seem to want them to be more than they are intended to be. I would recommend you read and absorb the link I shared earlier: https://www.osha.gov/Publications/OSHA3514.html
 
Thank you very much for the OSHA link. There is only one SDS sheet that I am unclear on, and it is for a LPG. The SDS says "Use explosion-proof electrical (ventilating, lighting and material handling) equipment.”

This SDS does not mention any Hazardous Areas in this statement, and does not make any differentiation between Div 1 and Div 2. It just says “Use explosion-proof electrical (ventilating, lighting and material handling) equipment.”

With that information, do you think it would be correct to then set my Div 1 Hazardous area and Div 2 boundary using Annex D of API RP 500? Would I still be able to use Intrinsically Safe wiring as a protection method in the Div 1 location, even though the SDS fails to mention that as being acceptable? I would think it would be ridiculous if the SDS limits me from using other protection methods like intrinsic safety installed to the control drawings...
 
I can only say that wiring methods must be consistent with the electrical area classification.

As I read the OSHA brief, it does not appear that the SDS you are referring to is consistent with the format as laid out. The preamble says an SDS must conform to the format or be reissued. The OSHA brief mentions Section 16 of a conforming SDS must have the date of its publication.
 
Do you think the "material handling" mentioned here only refers to the physical handling of the hazardous material, and not meant to refer to the electrical and electronic equipment involved in a process that uses the material....like filling or evacuating a vehicle with the hazardous material?
 
rbalex said:
..As I read the OSHA brief, it does not appear that the SDS you are referring to is consistent with the format as laid out. The preamble says an SDS must conform to the format or be reissued. The OSHA brief mentions Section 16 of a conforming SDS must have the date of its publication.
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It appears compliance is not possible, as the product violates SDS standards, regardless of interpretations on process or transport.

Perhaps the Op should look for another product, with a compliant SDS format.
 
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