Kohler says “no” to: Magic Eraser, Comet, Bar Keepers Friend, Zud, vinegar, etc…. for cleaning its porcelain enamel cast iron

IMPORTANT UPDATE:
If you are the owner of an older porcelain enamel bathtub or sinks, please see my May 2, 2016 story Understanding potential lead hazards in old porcelain enamel bathtubs and sinks and ceramic tile of any age; this article focuses on raising awareness around three other potential sources of lead dust exposure in your home – old porcelain enamel bathtubs and sinks and ceramic tile of any era, steps you can take to assess and, if required, address them, and makes it pretty clear why you should follow manufacturers’ care and cleaning recommendations relative to these products.

A note on terminology: I have seen the terms “Porcelain Enamel”, “Enamel”, and “Porcelain” each used to describe the top coating that is baked onto metal substrates on bathtubs, sinks and other products. As such, you may see the various terms used interchangeably on this blog by me and by others who are interviewed or commenting. To verify what types of products you have and what they are made of, do your own research including consulting with the original manufacturer or your own professionals.

I recently used a product called ROG1 to clean the dirty, slip-resistant bottom on my eight-year-old Kohler tub. I found ROG1 sold alongside another ROG product — ROG3, which is explicitly recommended on the Kohler website. The ROG1 worked well to lift off the dirt on my bathtub’s slip resistant bottom.  But, keep reading, because as you will see, ROG1 is not explicitly recommended by Kohler, so I went to try and dig deeper.

Readers’ comments, too, launched me into asking Kohler some more questions. ROG products are relatively expensive, and in their comments on my story (which I have now directed to this post so that readers can get this info from Kohler), a number of readers balked at the thought of the price. As alternatives, they began to recommend other, much less expensive products they said that they had used effectively to clean the porcelain enamel on their cast iron bathroom fixtures, including: Magic Eraser, Comet, Bar Keepers Friend, Zud, etc.. There also were mentions of baking soda, vinegar, etc..

Hmmmm. I was suspicious about using these products on the porcelain cast iron. I have used these products on various surfaces in the past, and sure, they can lift the dirt like nobody’s business. But I thought: If Kohler was not recommending these well-known cleaners, it might well be because they damage the finish on their porcelain cast iron bathroom and kitchen fixtures.

So I contacted Kohler and sure enough, they warn against using a number of these other cleansers because of testing and/or concerns that ingredients in them can harm Kohler’s shiny durable porcelain-enamel-on-cast-iron finish. Here is the text of our emails back and forth:

Pam to Kohler: In the comments section of my original story (now redirected here so that readers will see this entire discussion of Kohler-recommended products), a number of readers are saying how they use other products (not on your recommended list) including: Bar Keeper’s Friend, Zud, Magic Eraser, Comet, etc. My question to Kohler: Will these products ultimately etch the surface or destroy the high gloss on the cast iron or otherwise “damage” the cast iron finish?

Kohler PR responded:

Adam Horwitz, director of Kohler kitchen product marketing and cast iron development, tried to respond to the cleaning agents he saw in the comments:

Magic Eraser — Use sparingly only.  It can cause harm to the finish.  For example, you can use it to remove metal marks on a kitchen sink.  Another tip to remove marks from cast iron, scrub with a wine cork.  Not only will the sink get clean but you can enjoy a good bottle of wine.

Comet — Do not use.  It is an abrasive agent that will dull the finish over time.

Bar Keeper’s Friend — In our testing, we have found that Bar Keeper’s Friend can discolor the enamel when used over a period of time.

Zud — We have not tested Zud on our enamel.  However, we do see that it has similar ingredients to Bar Keeper’s Friend.

Pam to Kohler: What about home-made solutions using baking soda? What about vinegar?

Kohler PR responded:

Baking soda is fine since it is non-abrasive.  We have not specifically tested vinegar as a cleaning agent so we do not have data when it is used in a strong dose and left remaining on the sink.  Vinegar is acidic so it causes us some hesitation.  If homeowners are going to use it as cleaning agent, we recommend rinsing the area with water after use.

Pam to Kohler:  Why have you recommended the cleaning products you have recommended — and should owners of your cast iron fixtures avoid using anything but your recommended products and for what good reason?

Adam Horwitz, Kohler:

Kohler has done extensive testing of a variety of cleaning products and their effects on our cast iron products over time. We have listed the recommended cleaning products based on the results of this testing and advise that consumers avoid using other cleaners as they can dull or even damage the enamel coating on our cast iron products.

Pam keeps going, knowing she is probably being annoying and asks, “I’m curious about the active ingredients that are harmful”:

Kohler PR responds:

I am sure our development team could respond to a specific active ingredient question, but might not be able to address all active ingredients (there were many tests done, so the data is quite extensive).

Pam checks Kohler’s list of recommended cleaners and realizes that Kohler has explicitly okayed ROG3, but not ROG1 (which is the ROG product Pam used on her tub.) (Sorry to keep referring to myself in the royal third person — I’m trying to ensure the Q&A flows.) She asks Kohler about this…

Kohler checks and says:

ROG 1 is a cream cleanser (containing a mild abrasive) that is designed to remove stubborn stains.  We have not tested this cleaner on our enamel, but after looking at the MSDS, it appears to be safe (no acid).  ROG III [sic] is a liquid cleaner that is designed to clean and maintain the slip guard surface.  ROG 3 is the product we recommend on the Kohler Care & Cleaning website.

Again — See see on Kohler’s website for care instructions.

However, Pam is not done yet. On the ROG website, ROG1 (the cream cleanser Pam used) was described as “Kohler recommended” — but it is not listed explicitly as such on the Kohler website. So, Pam reaches out to the owner of the ROG product line and we talk about why this product is missing from the Kohler list. Then Pam sends Kohler another email:

Pam to Kohler: Thank you. Alas, I am not done yet… I reached out to the inventor of ROG1 and ROG3 and asked him why ROG1 had not been tested by Kohler. He said that, yes, it had been tested by Kohler — in the 1990s. Specifically, he said he worked with a man named [not included here, but provided to Kohler]. The inventor said that ROG1 was tested and approved then. Can you check this out for me? I just want to be as thorough as possible.

Kohler PR responds:

Hello Pam,

That’s interesting. I went back and double-checked, and our team says that we would have to retest with our current standards and knowledge. A test from the 1990s may be different from our current process. However, we have no immediate plans to retest it.

Hope this helps.

And there’s more…

Update on the labeling of ROG1:

Note, that in my subsequent use of ROG1 I saw that the label said it contained “Sulfonic Acid” — even though the owner of these ROG products says on their website, and has said on this blog in comments, that there is no acid in their products. So, I sent an email to ask about this discrepancy. Here is the exchange, and the company’s response:

I wrote to Vince Vallone, owner of the company:

This is Pam from Retro Renovation. I was just using ROG1 and noticed that an ingredient listed on the label is “Sulfonic Acid”. However, I don’t see this listed on the MSDS [link no longer available] <– linked here. And you said this as a comment, “Yes Gina the ROG products are not caustic, no acids, many folks don’t realize the the grocery store and walmart caries many acid contained cleaners and will dull the bathtub over years, magic eraser has acid, 409 scrubbing bubbles and many more.”

 

Can you clarify?

Thank you, Pam

Hello Pam

 

Hope all is well and we appreciate your follow up.

 

 The ROG 1 cream contains no acids.

 

After your e-mail….

Well we researched this and found the mistake and figured out what went wrong with the labeling.

 

We many years ago manufactured a deck and hull cleaner similar to the ROG 1 but it was called BCD’s deck and hull cleaner product named ROG 9

 

The ROG 9 Deck and Hull cleaner for the yachting, and boating industry this product had the sulfonic acid in the proprietary mixture and our bottle printer who prints the data on the bottle left this acid statement on the ROG 1 label, by mistake we never caught it till you mentioned it. Thank you, your new name should be retro-thour-ough-. LOL.

 

The ROG 9 was an experimental cleaner we tried years ago the formulas was to clean exhaust fumes on the aft side of the boat from inboard engines exhaust marks from the diesel engines and worked great but it never took off as expected so we stopped production on this product. Both were created around the same time, as we also had Glass cleaner and deodorizers, we no longer make.

 

But leave it up to you with your great journalism to find this mistake. Again thank you, we have now taken steps to remove that error from all future ROG1 bottles.

Thank you for looking at our mistake and we have now taken steps to remove this on all the ROG 1 bottles.

Pam returns solidly to the first person. Are you still with me?

Repeating some key links:

• Kohler-recommended products: See Kohler’s page on the care and cleaning of their porcelain on cast iron sinks, tubs and shower bases here. <– This page includes their list of recommended products for cleaning cast iron — the glossy part, and the special slip-resistant bottoms.
• See Kohler’s concerns about using harsh cleaners or abrasives — take note of Kohler’s warnings about the other products discussed at the beginning of this story.
• Again: If you are the owner of an older porcelain enamel bathtub or sinks, please see my May 2, 2016 story Understanding potential lead hazards in old porcelain enamel bathtubs and sinks and ceramic tile of any age; this article focuses on raising awareness around three other potential sources of lead dust exposure in your home – old porcelain enamel bathtubs and sinks and ceramic tile of any era, steps you can take to assess and, if required, address them, and makes it pretty clear why you should follow manufacturers’ care and cleaning recommendations relative to these products..
  
• Please do to your own research — talk to your products’ manufacturers — so that you can make informed decisions about what cleaning products/processes to use!