Written By: Matthew Greer, Technical Writer, PSC Biotech®

People need their water to be clean, pure, and free from any threating microbes. This is even more imperative when it comes to pharmaceutical manufacturing, especially with injectable products.  Pharmaceutical grade waters must meet the requirements in their pharmacopoeia monograph, so how do you prove that for your Purified Water, Water for Injection, and other waters?  You have a program to regularly monitor, sample, and test the waters from your water systems.

Sampling collects samples that are uncontaminated by the sampling process from all the designated water system test points within a specific time frame. Sampling begins with getting the right containers for each test you want to perform.   

  • Pyrogen-free polystyrene tubes for Endotoxin
  • Sterile bottles for Bioburden
  • Clean tubes for Total Organic Carbon (TOC) and Conductivity
  • Sterile bottles containers including sodium thiosulfate tablets for coliforms
water testing

Generate your paperwork before collecting the water samples. Identify which outlets need to be sampled.  Prepare your sampling containers.

Label the sample containers.  Labels should contain the sample port identification, the analyst initials, the date of sampling, the time of sampling, and the type of testing that needs to be performed on the sample.

When you enter the area where the sample port is located, don the appropriate personal protective equipment (PPE) to collect the sample e.g., sterile gloves, long sleeve lab coat, safety glasses, heat resistant gloves, if needed.  Remember, Hot Water for Injection is HOT!  If you are wearing heat resistant gloves, wear a pair of sterile gloves over the heat resistant gloves to help maintain the integrity of your clean sample containers.


Collect your water samples according to your written, approved procedure.  Your sampling procedure shouldconsider how the water is used from that specific sample point.  For example, if the water will be used directly from the point of use without a hose, sampling must occur directly from the outlet using aseptic technique. Typically, the sample port is turned on and allowed to flush for at least one minute at full flow. Once the sample port is flushed, the samples are collected in the appropriately labeled containers. The lids should be held in a face down manner to help prevent microbial contamination and replaced on the filled sample container as soon as possible in an aseptic manner. 

Ensure the containers are labeled with the port number, time and date of collection, analyst initials, and analysis type.

Once sampling is done, the samples need to be submitted to your Quality Control laboratory and timely tested or properly stored according to USP <1231> and your written, approved procedures.  

Once you get the data, you use it to monitor your water systems.  Track and trend your data.  Analyze your data.  Verify your test results are below your Alert and Action levels.  Look for trends that predict problems with your pharmaceutical water systems. 

Alert your water users so that they are aware of the water system status, good or bad, every day.  You want your water users to know they can use your pharmaceutical grade water because you notify them that your waters meet their specifications and not guess that it is OK. 

If you have water questions, PSC® has answers and help.

PSC Biotech® has the resources and professionals available to ensure that your facility is up to cGMP standards when water testing.  It is our professional services mission and pleasure to assist your team with your water needs.  PSC® is your source for comprehensive services to keep your facility, systems, and processes in a “state of control”.  From training to validation, audit preparedness to equipment rentals and sales, PSC Biotech® has the people with the skills and tools to meet your needs.

Contact us today!