Sampling Dangerous Materials

Perhaps use some kind of large syrenge type device?

They use a long plastic tube dipper with a valve designed to close when they push the dipper down against the bottom so they obtain a representative sample of the entire column. I am not sure that the small release that occurs during sampling of the materials you have described is of any concern, most of the acids are hazardous only in some quantity, and some of them like acetic acid are common in very large quantities just in household ingredients (e.g. Vinegar). The remediation of such releases of materials is frequently just an issue of diluting with water and/or reacting with a neutralizing agent like sodium bicarbonate, lime or other materials. The issue of spillage on the side of the tankers is a problem as they need to be clean for transport (becasue law enforcement should not be expected to comprehend the hazard from the material, they just know there is something hazardous staining the side of the trailer). The spillage frequently occurs from remenant drainge off the outside surface of the dippers, sometimes infrequently one is not closed fully or does not close properly but this type of spillage should be avoided by withdrawing the dipper over the access portslowly to observe for a leak before pulling it fully away from the opening.

Never done that before, but:

How about something like a high-tech turkey baster, suck up a small sample

and transfer it at the sampling point, while still over the manway.

Don't go "down a stair or loading rack and pour it to a container."

Yep, same concept, syringe/turkey baster. Simply a device to "suck" the fluid into its body, reducing/eliminating the possibility of a slosh/spill, while reducing possible outside contamination. Might I add it could be a cheap solution as well.

I cannot believe that this is the best way to sample. Why do they need the sample prior to hooking up and emptying car? Why not draw off sample from a separate sampling valve that you could attach to the cars unloading valve?

Hook up a flexible hose to tankcar unloading valve.

I'm presuming that this "sampler is wearing full PPE as required by MSDS sheets?

Oh, climbing up on car top, probably not...

here's recommendation for acrylic acidfrom MSDS sheet:

http://www.sciencelab.com/xMSDS-Acrylic_Acid-9922794

"Ensure that eyewash stations and safety showers are proximal to the

work-station location.

Personal Protection:

Face shield. Full suit. Vapor respirator. Be sure to use an approved/certified respirator or equivalent. Gloves.

Boots.

Personal Protection in Case of a Large Spill:

Splash goggles. Full suit. Vapor respirator. Boots. Gloves. A self contained breathing apparatus should be

used to avoid inhalation of the product. Suggested protective clothing might not be sufficient; consult a specialist

BEFORE handling this product."

end quote.

What you described would never be permitted in the plants where I used to work.

milo "there should be a sampling offtake valve available on plumbing once the car is hooked up; based on analysis the car could then be pumped, or the valve closed and the only disposal is the product conatined in the offtake hoses and pipes which you would purge to a waste tank for neutralization."

Try this - after reading MSDS and being prepared!

My concern about this type of sampler was reaction of chamical with the rope/wire/line.

I used these to collect samples of subsurface waters when doing lake water ecology studies back in the day. they are called kemmerer samplers

http://www.rickly.com/as/kemmerer.htm

Again. MSDS and shower eyewash concerns, also glovesand handling.

milo

That is one of the reasons for reading the msds first

YOU GOT THAT RIGHT!

milo

Thank you for all the thought full comments.

A few clarifications and reply:

The plant uses manufacturer's recommendations for sampling. Doing this for over 20 years without an incident. They recognize that does not make it the best way.

Existing procedures do include MSDS, required PPE for the job and when it is required, JTAs (Job Task Analysis) are up to date and annual training is well documented.

The turkey baster approach would replace a "cup on a six foot stick" with a device that would then need cleaning, storing and decontamination. It was considered and overwhelminggly rejected becaues of the additional risks, work and mechanical difficulty (and the lack of a third hand). It would be a big baster or a "sludge judge" device. They have been problematic, and the preferance is to keep it simple.

The reason for sampling is simple; quality control. Many samples are visually inspected and held until products are made, others have HPLC, GC, Refractive index or some other check done and compared against the CoA.

Yes, shipments have been rejected because of the incoming inspection process.

Some trucks and cars do have a sample nozzle procedure at the unloalding tubing. This is used when there is a vapor recovery system (glacial acetic acid for one) These sound good but in practice generate 3-5 gallons of waste before the piping between the internal and external valve is filled and purged. Where do you pour 20 pounds of glacial acetic acid, without contaminating the area with acid vapors requiring evryone downwind to wear respirators?

Our concern remains walking sown stairs with open container and the "chain of custody" path with container contamination and sample cup spilling.

If you don't know how it should be done, you shouldn't perform this task!

Hire a qualified industrial chemist for a day and avoid an accident.

An engineer's must know when he is not qualified to do the work. Especially when it is safety related.

You cannot just try anything and see what you can learn from it.

Are the cars unloading from the top or the bottom?

Rail cars are unloaded from the top. Tank trucks are unloaded from the bottom. It is policy to not pressure unload any bulk delivery. All product is pumped out. The only deviation is the railcar's unloading pump will not pull enough vacuum to pull out the top of the car to prime them. A slight pressure pad is used to push liquid up to the rack and into the pump suction this primes the pump and it can pump out.

My initial thought of using a bottoms valve didn't pan out when I googled it. Does the following make sense to you?

For caustic, one supplier recommends lowering a small-necked bottle into the tank car or truck and rapidly lowering and then raising the bottle through the tank contents to get a representative sample. I would imagine it is similar for other chemicals as well.

http://www.pollardwater.com/pages_product/SafetyAcidCaustic%20Sampler.asp

Take a lid up with you and once sampled, disassemble the sampler and cap the sample. Wash everything with water and then you can take the closed container back down the stairs for analysis. Obviously, PPE is requried for this operation.

Dipping or using the bottoms valve are not recommended since it doesn't take a sample through the gradient of the tank.

Paddler,

I have used a device in the past to sample from vessels, that looks like this:

It holds a sample bottle at the bottom of a telescoping (stainless steel) pole, with a separate rod being connected to the bottle's lid, so that the bottle could be opened and sealed "remotely", at whatever depth the sample was desired to be drawn from.

Check out benmeadows.com for this device.

(They call it a "sub surface grab sampler")

This company also sell a simpler device, that holds an open sample bottle at the end of a telescoping pole.

(They call it a "swing sampler")

I have used a similar, (homemade) device to "grab" sample the contents of frac tanks from the manway, as well as cooling tower water for legionella.

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In your application, this would probably be an improvement over walking around with a open-topped teflon "dipper"; however you will still need to address the decon/safe handling of the pole, which will be literally dripping with caustic/corrosive liquids after each use.

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Just my $0.02...

Thank you Betamachine and Jman.

I can understand your responses very well.

A little feedback is in the case of 45-50 % caustic my experience is that because of the very high density, contaminates are either floating on top or in the rag layer or settled on the bottom as solids. My understanding of day tank circulation at most caustic suppliers gives me confidence the container is usually homogeneous. If you ever look into a tank car before unloading you would understand the floating crud issue.

Although Acetic acid (in a very dilute form) is vinegar, our application is "pure". It freezes at 61 Degrees F, the vapors flammable and very irritating over large areas with a small spill. The heat of dilution is significant if water is added. I am always concerned someone thinks this is vinegar and not respect it.

My concern is not extracting the sample from the shipping container as much what is accepted practice for handling the residue, drips, collected wastes applying the label and hand off to the lab.

We have tried (and sometimes use) the jar dippers shown in one post. One of the problems with the dippers is the limited size of the collection bottles. We retain many samples for six months in shelving and racks that accept certain size jars. Dipper jars need a separate step to pour to the right jar, under a hood with PPE and another disposal problem, potential exposure and adds a step to the workload.

Thanks again for the response,

Paddler

Hello Paddler,

You may find this helpful

http://www.osha.gov/dts/osta/otm/otm_ii/otm_ii_4.html

I am still looking for help on this.

I understand your worry, as any test of a potentially dangerous substance, done on a regular basis, can get sloppy and taken for granted?

I think you should make sure there is a different large pipette or syringe used for each liquid substance, and these should be clearly marked.

Take care..................

20 years & no problems - how lucky can you get - you must be due for one.

Sounds like the blind are leading the blind again! - I give up