Thursday, July 26, 2018

Case Study: The Musculoskeletal Transplant Foundation (MTF) Isolator

The Musculoskeletal Transplant Foundation (MTF) is the nation’s leading tissue bank. MTF designed and validated the use of isolators in the production of DBX Demineralized Bone Matrix (DBX) putty. DBX Putty is the combination of demineralized bone and sodium hyaluronate for use during surgical application. Since the DBX putty is introduced into the body, it must be produced and packaged under aseptic conditions and procedures. Aseptic technique refers to efforts to maintain a sterile field during a procedure to prevent infection. In order to maintain the highest aseptic techniques, it was decided to move the DBX Putty process to isolators for their ease of use in cleaning and decontamination. The process whether conducted in a clean room, biological safety cabinet, or an isolator is largely the same with the exception of the decontamination cycle.

In order for this process to be economically feasible, the decontamination cycle had to take less than 2 hours.  If the decontamination time exceeded 2 hours, then it would not be cost effective enough to warrant the change from clean room processing to isolation processing. The choice was between vapor phase hydrogen peroxide and chlorine dioxide gas. Both methods are registered with the US-EPA as sterilants, and both have been used in clean room environments and in isolators. The VPHP process produced varying amounts of condensation with potential for poor distribution and penetration abilities into gaps and small openings. Based on these limitations, chlorine dioxide, a true gas at room temperatures, was chosen due to its fast cycle times and evidence of its effectiveness.  With the reduced cycle times, MTF’s decision to move forward with isolators became feasible. The isolators eliminated the need for using 2.5 ISO 4 clean rooms and provided true aseptic processing.  The chlorine dioxide gas generator and isolators worked together to provide a simple and seamless systems integration.

To learn more about the Musculoskeletal Transplant Foundation’s selection, design, and validation of isolators for aseptic processing with chlorine dioxide gas, read Nick Barbu and Robert Zwick’s article in Pharmaceutical Engineering here.

Tuesday, July 17, 2018

Material Compatibility - Electronics

Material compatibility remains one of the largest question marks for those looking to use chlorine dioxide gas, and there’s a lot of conflicting information on the topic.  Chlorine dioxide gas cannot be stored and shipped, so it must be generated at the point of use.  The method of generation, and its resulting purity, has a great impact on the material compatibility of the chlorine dioxide gas product being used.  One of the first large scale decontamination projects utilizing chlorine dioxide gas was the oft referenced Hart Senate Building decon performed in November 2001.   It was performed by a company who previously used its CD gas technology for controlling odors in oil wells. As material compatibility was never an issue in this previous application, they used a less refined process of generation which contained acidic byproducts. When used in the Hart Senate Building, some material issues and corrosion occurred. ClorDiSys was established after this, and our chlorine dioxide gas is generated by passing a low concentration chlorine gas through a proprietary sodium chlorite cartridge to convert the chlorine gas into pure chlorine dioxide gas. Our process does not leave a residue and does not require any additional clean up once the gas has left the space.

ClorDiSys has done studies with electronics and found that they stand up well after multiple exposures. Computers have been exposed to the gas for over 25 cycles and have been fully functioning afterward. In fact, chlorine dioxide gas was chosen to decontaminate the inner chambers of a $3,000,000 Transmission Electron Microscope over hydrogen peroxide vapor because of its superior material compatibility as proven through manufacturer testing. The US Environmental Protection Agency (EPA) commissioned a study exposing computers to chlorine dioxide and hydrogen peroxide over the course of 6 months. Below are the test results showing chlorine dioxide had the lowest amount of failures.

Not all chlorine dioxide gas products are the same, and we understand the hesitation considering some of the information available regarding corrosion.  That’s why we offer free* material testing to give confidence that our chlorine dioxide gas will be safe on your materials and sensitive items.

* Testing is free for a reasonable amount of items.  Shipping not included

Friday, July 13, 2018

Ultraviolet Light in HVAC Systems

Mold, mildew, and dangerous diseases, such as Anthrax, Influenza, Measles, Smallpox, and Tuberculosis, are often spread through airborne transmission. Mold spores easily disperse, wreaking havoc in the new environments they land upon. A solution to continuously combat harmful organisms is the introduction of ultraviolet light disinfection. Ultraviolet light is divided into UV-A, UV-B and UV-C rays. It is the wavelengths in the UV-C spectrum, specifically 265 nm, that offers the greatest germicidal potential.  When a microorganism is exposed, the nuclei of the cells are altered due to photolytic processes. This process prevents further replication and causes cell death.

Ultraviolet light disinfection systems can be placed directly within HVAC ducts to both eliminate and prevent mold, mildew, and other organisms from forming and spreading.  Unlike HEPA filters that solely trap organisms, allowing them to flourish and possibly be re-released into the environment, UV-C kills organisms, eliminating that risk. Placing UV-C disinfection units within the HVAC system provides a continuous disinfection cycle with no harmful effect to anyone present in the space.  Units can be placed in the supply and the return to maximize the benefits.  Units placed in the return ducts have an even greater benefit, because the slower air velocity allows for additional exposure time. Ultraviolet light disinfection is an easy, hands-off, chemical-free way to reduce the risk of mold and mildew from developing and the spread of disease causing airborne organisms.

Attend the upcoming UV Light for Healthcare webinar on July 19th and UV Light for the Life Science and Pharmaceutical Industries on August 7th to learn more.

Thursday, July 5, 2018

Can Chlorine Dioxide be used with Organic Foods?

ClorDiSys is occasionally asked if chlorine dioxide can be used in organic foods or in organic processing facilities. The short answer is yes.  More specifically, according to 7 CFR part 205, SUBCHAPTER M—ORGANIC FOODS PRODUCTION ACT PROVISIONS, the use of chlorine dioxide is allowed, but it comes with some restrictions. Its use is permitted for Livestock Management Tools and Production Aids, for Processing Sanitizers and Cleaners, and for Crop Management Tools and Production Aids. The common restriction across all three applications is the residual chlorine levels in any final rinse water or water in direct contact with food products or animals. The water cannot exceed the maximum residual disinfectant limit under the Safe Drinking Water Act (0.8 mg/L or 800 ppb). Reference the label of the product you are using to establish proper use corresponding with such restrictions. Visit the websites below for additional information to see if your organic operation qualifies for chlorine dioxide usage.


Organic Materials Review Institute,

Title 7 Agriculture → Subtitle B → Chapter I → Subchapter M → Part 205—NATIONAL ORGANIC PROGRAM

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