Are all R.O. machines being used required to have a product water diverter valve or does this apply only to R.O. machines manufactured after 8/2001. Thanks

Here's what AAMI RD 62 says:

"In addition, it is RECOMMENDED that when a reverse osmosis system is the last chemical purification process in the water treatment system, it includes a means to prevent patient exposure to unsafe product water, such as a diversion of product water to drain, in the event of a product water conductivity or rejection alarm."

This recommendation is in addition to, a requirement that:

1) The R.O. shall be shown to be capable at installation of meeting the requirments of the Table1 when tested with typical feed water of the user by the methods of (section) 5.2.2.

2) R.O. devices shall be equiped with on-line monitors that allow determination of rejection rate and product water conductivity. That the product water conductivity monitor be equiped with both audible and visual alarms, with the audible alarm "audible in the patient care area".

IF deionization is used as either the primary or final chemical purification process in the system it is REQUIRED that the quality be monitored continuously, with a minimum set point of 1 megohm resistivity at 25 degrees C. If the resisitivity falls below 1 megohm an audible alarm, audible in the patient care area shall activate and "product water stream SHALL be prevented from reaching any point of use, for example by being diverted to drain"

So the answer is that RD62 as of 8/2001 DOES NOT REQUIRE but does RECOMMEND that a product divert be employed if the R.O. is the last cheimical purification process, of the system. It DOES REQUIRE that a product divert or other means of preventing poor quality water from reaching any point of use, be employed if D.I. is the last process for treating the water in the system.


AAMI RD62 Water Treatment for Hemodialysis Applications (8/2001)

[This message has been edited by Dennis Todaro (edited 05-17-2002).]

Dennis,
Just a small point. The AAMI document RD-62 was published in August 1991 not 8/2002.
Thank you
Lee

Further clarification:
AAMI RD62 was published in April 2001 as a revision to RD5, 1992.

Thanks Lee and Mark,

Not to be-labor the point and just to clarify, obviously my listing of 8/2002 was a typo since it is only now May 2002.

Section RD62 of the 2001 Edition of AAMI Standards and Recommended Practices - Dialysis which I refered to, says APPROVED by ANSI 6 August 2001.

The fact is we are all correct. Some may find this boring but here's the history of this recommended practice:

RD5 "Hemodialysis Systems" was first approved and published in 1982 under the designation RD5:1981 (1981 being the year, the standard was developed by the committee, 1982 the year it was approved by ANSI)
RD5 was first revised in 1992 (RD5:1992, 2ed). In 1996 it was decided that to 'better serve the dialysis community' concentrates, water and equipment were separated into individual standards. RD61:2001 is the standard for Concentrates, RD62:2001 is the standard for water, these new standards supersede RD5. RD5:200X (which was still in draft as of my book's publication) will then be the standard solely for hemodialysis equipment.

The process of developing and revising standards is much akin to the procreation of elephants. Existing standards are reviewed every 5 years. The committee will start the process develop inumerable drafts for review and will then publish the standard. This final published standard is then submitted to ANSI the American National Standards Institute for approval.



[This message has been edited by Dennis Todaro (edited 05-17-2002).]

Back to Lifer's original question. After giving it some thought - while the AAMI standard does not require but only recommends that an RO have a product divert, the fact is that the AAMI Reuse Recommended Practice has been "incorporated by reference" into the Medicare Conditions of Coverage". The incorporation by reference allows for an automatic inclusion of revised standards within the COC without further action by congress. Under this concept the "Recommended Practice from AAMI" becomes a requirement under of the Conditions of Coverage.

Because the Recommended practice refers to the other standards, revisions to those standards also become requirements by virtue of the "incorporation by reference".

Therefore question then becomes if AAMI recommends something are we required to follow the recommendation. This is a matter of interpretation.

Dennis,
Thank you for the update on how CMS (formally HCFA) adopts a standard. If you look further into the subject you will learn that standards are for manufacturers and recommended practices are for users. The sections of RD-5 that was for the user, mainly the appendix B, is being removed.
The replacement for the user sections of RD-5 will be a new Recommended Practice, now under development, RD-52 Dialysate for Dialysis. This will address the users responsibilities toward water testing, dialysate testing and the general maintenance of the entire fluid system.
Since this is addressed to the user it is one to watch.

Just a little more history. It was found when RO use was first begun, that there was a natural equalization of solute from feed to permeate sides. Since the RO shuts down in the concentrated state, the permeate can actually be higher than the feed water. It was also found that due to the relaxed state of the permeate tube o'rings, bacteria can grow through into the permeate path.

To overcome this problem, it was normal to run RO machines 24/7 in critical applications. In large RO-DI systems the cycling of the RO caused loading which resulted in early exhaustion of the beds. In the late 70's, it was found that the permeate could be diverted during start-up and the loading was eliminated. Further results showed that the bacteria loading was also greatly reduced. Further revisions resulted when dialysis needed a safety check due to a faulty water softener (6-10,000 ppm Sodium entering the RO). Although a machine with high membrane pressure shut-down can catch the situation, the permeate has already gone way past AAMI Standards. The conductivity monitor was added into the game and has resulted in what we are currently seeing on RO machines.

Guess that's all from me.

Life is GOOD
Willie B