Tech Center

Gas chromatography: Not recommended for area monitoring of ethylene oxide in SPD departments

Our friends at Interscan have just posted a lengthy (ca. 1100 words), but informative technical brief on the pitfalls of using gas chromatography to monitor EtO in hospital settings.

The article, typical of the Knowledge Base content the company offers on its website, is pretty much non-commercial, while explaining key concepts in gas detection. Included in the piece is a detailed history of EtO exposure regulations, dating from 1968 to the present.

Give it a spin.

Techie stuff on the date of Easter

Many people have noticed that Easter is quite late this year. In fact, April 24 is almost as late as it can be. According to ecclesiastical rules, Easter can never occur before March 22 nor later than April 25.

For a detailed explanation on how the date of Easter is determined, surf over here.

For Baby Boomers who claim that they have cannot remember Easter being on April 24, you're right. The last time Easter occurred on this date was in 1859. However, in 1943, Easter fell on the latest date it possibly can: April 25. The next time that will occur will be in 2038.

As to early dates, check this out...

The last time Easter fell on March 22 was in 1818, and this will not occur again until 2285. Looks like we missed out.

The most accurate conversion utilities on the Web

Yes, they really are. I'm talking about the conversion utilities that apply to common units of measurement for gas concentration.

For some years, the good folks at Interscan have made available on their website downloadable Excel spreadsheets, to perform such conversions as parts-per-million to milligrams per cubic meter. Since these calculations take into account ALL necessary parameters (unlike most other web-based "converters") as well as maintain at least two decimal places, they truly are the most accurate on the Web.

Recently, Interscan updated the converters. They are now easy-to-use script based utilities, requiring only a few keystrokes. The conversions are made on the fly.

By way of background, Interscan also offers an informative Knowledge Base article on the stupidity of some of the alternative units of measurement.

Can technology keep up with regulatory zeal?

Our friends at Interscan have prepared a nifty PowerPoint presentation entitled "Issues with low concentration gas detection in ambient air."   (1.9 MB)

While this may seem like an arcane subject, it really shouldn't be. Virtually every industry is affected by regulatory agencies that set compliance levels, and keep lowering them, for the level of toxic compounds in ambient air. Yet, the pitfalls of attempting to measure these concentrations are not well publicized—at all.

Interscan details three areas of concern:

  • Calibration issues
  • Zero gas issues
  • Interference issues

The information presented is practical and easy-to-understand. What's more, unlike so many other authors of PowerPoint content, Interscan distributes the native file, rather than a pdf version.

I mention this because, as one who does PowerPoints himself, distributing only the pdf versions has always seemed ridiculous. With the pdf, you lose all the cool formatting, and that's at least half of what makes a good presentation. Years ago, this practice could be justified since it reduced the file size, but with today's broadband speeds, it is no longer appropriate.

Interscan offers additional PowerPoint shows for free download, as well.

Check them out.

Interscan's all new Arc-Max® looks like a winner

Interscan was the first company to realize the importance of data logging in the field of gas detection, coming out with its dosimeters way back in the early 1980s. This was followed by a complete data acquisition/archiving/reporting package called Arc-Max®, introduced a few years later.

When Windows arrived on the scene, Interscan revamped Arc-Max to be based on a SCADA (Supervisory Control and Data Acquisition) engine—for enhanced reliability and compatibility with sensors besides its own.

This latest version of Arc-Max is more user-friendly, and lends itself better to customization. Process and environmental sensors can be mixed and matched more readily, and the reporting features can be tweaked to give you exactly what you want.

Virtually all common communication protocols are supported, and the new system is easier to network.

Grab more information here.

EPA gets involved with ethylene oxide usage

Ethylene oxide (EtO) is an essential sterilant, used for all sorts of devices that can't take steam processing. For some years, it has been fashionable to pile on this compound. Yet, pesky data—tracing morbidity and mortality of EtO-exposed workers and comparing it to the non-exposed population—shows essentially no difference (beginning in the OSHA era).

Older EtO sterilizers were used in conjunction with separate aerators, so that workers had to unload the sterilizer and place the load into the aerator. Technically, this provided an additional exposure, compared to more modern sterilizers that have built-in aerators.

One would think that such practices would logically come under OSHA, but since ethylene oxide is considered a pesticide, EPA enters the picture.

Pesticides have to be registered and re-registered, so certain new guidelines for EtO came into effect on March 1, 2010, the most important of which is to prohibit the use of separate aerators. Or, to put it more positively, only single chamber sterilizers are now to be used.

The good news for EtO, though is that EPA also found that:

[T]he benefits of EtO use outweigh the occupational risks associated with its use provided that the risk mitigation measures outlined...are adopted and label amendments are made to reflect these measures.

Interscan has posted a Knowledge Base article on this matter, and I would encourage all in health care who might be affected by the new regs, to surf on over.

Ethylene oxide (EtO) techie stuff

Our newest Knowledge Base article gets into measurement ranges for EtO monitoring instrumentation. In so doing, we had to take a hard look at certain OSHA documents, as well as examine some literature references.

More often than you would think, references cited in a particular article don't necessarily support the contention being made. We link to a comprehensive report from 1989, and most of its content is still excellent. Too bad the authors who referenced it couldn't quote it properly.