Micro Water test specification

We have another corrective action in regards to testing our water source (to clean equpiment) for micro. The plan that we submitted was to send our water with a contract lab for micro. Our auditor wanted more information as to what our water spec would be. I tried looking for regulations and EPA if they have a criteria for water spec for cleaning. Is there anyone that can help me with this?

Thank you!

QAfood,

Please take a look @ http://water.epa.gov...nants/index.cfm. Generally, water used must be portable and at least be tested for total coliform, E.coli and total HPC. There are other of the EPA list that you may want to test for depending on the history of the water source. Also, if your water is supplied municipally you may want to get the annual quality reports.

QAFOOD -
Usually you can contact your local Health Dept office and obtain sample containers and then go back to them for shipping to your state Health Dept lab. Pricing is typically less than a contract lab. Only testing will be for potability, as SPL noted.
You might check with your state's Health Dept or look on their website. In Arkansas, all water source potablilty testing - which includes multiple samples per month - is posted on the department's web site. I have my QAMs print out the current ones once a quarter and drop in the file.
SPL also mentioned the annual water quality reports for municiple water sources. These are calendar year reports that are issued by July 1. Should be able to just ask the municiple water source office for a copy. These reports cover the comprehensive testing (physical, chemical, microbiological) that are conducted on the water source to meet EPA requirements.

Our water samples are tested by a University lab here in conjunction with the State. Their test is for coliforms, and the only acceptable criteria for their test standard is "Absent".

We have another corrective action in regards to testing our water source (to clean equpiment) for micro. The plan that we submitted was to send our water with a contract lab for micro. Our auditor wanted more information as to what our water spec would be. I tried looking for regulations and EPA if they have a criteria for water spec for cleaning. Is there anyone that can help me with this?

Thank you!

Hi there,

WHO have guidelines for water quality, a couple of example pages attached.

 WHO Drinking Water Guidelines page 122.pdf   181.08KB   105 downloads

 WHO Drinking Water Guidelines page 130.pdf   236.73KB   84 downloads

Are you extracting your own water? if not your supplier should provide a specification for the water they are supplying.

Normally you would monitor incoming water and at point of use, you would want coliforms to be absent in 100mL and TPC of < 100/mL in treated water (See below).

WHO guidelines describe these parameters the most commonly measured to assess microbial safety:

E. coli: Thermotolerant coliforms may provide a simpler surrogate.
Residual chlorine: Taste does not give a reliable indication of chlorine concentration. Chlorine content should be tested in the field with, for example, a colour comparator, generally used in the range of 0.2–1 mg/litre.
pH: It is necessary to know the pH of water, because more alkaline water requires a longer contact time or a higher free residual chlorine level at the end of the contact time for adequate disinfection.
Turbidity: Turbidity adversely affects the efficiency of disinfection.

Australian guidelines prescribe:

Thermotolerant coliforms (or E. coli) should not be detected in a minimum 100-mL sample of drinking-water.
Colony counts should only be used as an adjunct to routine monitoring for coliforms and thermotolerant coliforms (or alternatively E. coli). When a large number of organisms is detected, some form of remedial action is recommended, such as cleaning storage tanks or inspection and repair of the reticulation system.
The numbers should fall substantially during treatment processes. Generally, colony counts would be as follows in well-maintained supplies (using the Pour Plate technique with Plate Count Agar, at 35-37°C for 48 hours):
Disinfected supply <100 colony-forming units/mL
Undisinfected supply <500 colony-forming units/mL.

Regards,

Tony