Is it crucial that you have a reliable supply of pure or ultra-pure water in your laboratory?
During a recently yearly service of the Purific system pictured below, we found that it had been installed in 1998 and has been in operation ever since. That’s 24 years of service and counting.
We are passionate about what we do, and it is exhilarating when we see a Purific still supporting our customers core laboratory after all these years.
Concerned about service and reliability?…We’d love to talk.
Reverse Osmosis is a technology that is used to remove a large majority of contaminants from water by pushing the water under pressure through a semi-permeable membrane.
How does reverse osmosis work?
Reverse Osmosis works by using pressure on the feed side of the RO which forces the water across the semi-permeable RO membrane, leaving almost all (around 95% to 99%) of dissolved salts behind in the reject stream. The amount of pressure required depends on the salt concentration of the feed water. The more concentrated the feed water, the more pressure is required to overcome the osmotic pressure.
The purified water that passed through the RO membrane, is called permeate water. The water stream that carries the concentrated contaminants that did not pass through the RO membrane is called the reject.
For more in depth reading click here to read what puretecwater.com says about reverse osmosis.
A common problem labs have is that the filter housing (bowl) gets tightened too much when the Ion-Ex or 1 Micron filters are changed and the next time they need to be replaced it seems like it is impossible to loosen it.
When doing up the bowl make sure the O-ring is in place and has not fallen out, without the O-ring the filter housing can seize as there is little give in the head and it plastic on plastic.
Bowls should only be done up by hand. The seal is provided by the O-ring, so it should be replaced if it does not seal when don up hand tight. The black spanner is intended for for loosening the housings.
IMPORTANT: If the bowl is over tightened they can crack as the styrene material it is made from can be quite brittle.
Any organic molecule you break down you will find carbon in. Total organic carbons (TOC) is the amount of carbon found in an organic compound and can be used a indicator of water purity.
Water also has inorganic carbon (IC) but IC is not included in the TOC measurement. (TOC = TC – IC)
How does does TOC affect me as a pathologist?
This is where the importance of consistently pure water becomes essential. In pathology impure water can give false readings of samples, incorrect analysis and diagnosis of medical conditions and contaminate your analyser.
As a guide the following levels of TOC are what are acceptable in type 1,2 and 3 water as according to the American society for Testing and Materials (ASTM)
Type 1 2: <50 ppb of TOCs
Type 3 : <200 ppb of TOCs
Water quality parameters for ISO grades.
Perameter
Grade 1
Grade 2
Grade 3
pH value at 25oC
—
—
5.0-7.0
Conductivity (μS/cm) at 25oC, max
0.1
1.0
5.0
Oxidisable matter Oxygen content (mg/l), max
—
0.008
0.4
Absorbance at 254 nm and 1 cm optical path length, absorbance units, max
0.001
0.01
—
Residue after evaporation on heating at 110oC (mg/kg), max
—
1
2
Silica (SiO2) content (mg/l), max
0.01
0.02
—
American Society for Testing and Materials (ASTM) The ASTM uses D1193-06 and has four grades of water (see table below).
Water quality parameters for ASTM types.
Perameter
Type I*
Type II**
Type III***
Type IV
Conductivity (μS/cm) at 25oC, max
0.056
1.0
0.25
5.0
Resistivity (MΩ-cm) at 25oC, max
18.0
1.0
4.0
0.2
pH at 25oC
—
—
—
5.0–8.0
TOC (μg/l), max
50
50
200
No limit
Sodium (μg/l), max
1
5
10
50
Sodium (μg/l), max
3
3
500
No limit
Chloride (μg/l), max
1
5
10
50
*Requires use of 0.2 μm membrane filter; **Prepared by distillation; ***Requires the use of 0.45 μm membrane filter.
Buchanans Group Pty Ltd has recently completed the acquisition of Purific Industries with the purpose to continue its reliable service to pathology laboratories nationally and ensure its growth in the future.
Founder John Atkinson is staying on as a vital member of the team. Having many years of experience in water purification and the pathology industry and a passion for the industry, he will be maintaining a technical advisory and manufacturing role within the new entity.
Buchanans Group brings a team of energetic and passionate individuals whose collective purpose is to improve the lives of our clients, Staff, and suppliers. With pathology being central to the diagnosis and analysis of all diseases affecting humanity, our team is extremely pleased to be able to support the pathologists who advance medicine and preserving life.
We would value any feedback you could give us, as we are fully committed to ensuring the continuance of Purific’s reliability.
