Thanks to everyone who responded. I've learned a lot. Below is an email I got from one of the manufacturers of a Krypton PID lamp which explains things nicely. I understand that UV in this band known as VUV or Vacuum Ultraviolet is quickly absorbed in air so unless you are very close to the window there is no hazardous UV present. Since the window in the PID requires frequent cleaning we will interlock the enclosure to power down the lamp during that operation. The other areas of concerns mentioned by many of you we will also keep in mind and deal with. Thanks again for your help. The Other Brian ------ Dear Brian,
first of all I would like to know, whether you are intending to use a DC or a RF PID lamp, since general safety precautions are a bit different. Secondly we always recommend not to look directly into UV sources, although regarding the UV-output of Krypton PID lamps there are little safety concerns. The overall UV-intensity emitted by a PID lamp is very low. The bulb consists of a glass that actually blocks the VUV-lines used for the ionization process. So, the light emitted through the bulb is mainly in the visible and not harmful. The window consists of MgF2 and is actually transmitting deep UV light. However, the VUV-lines of Krypton between 117 - 180 nm are absorbed in air within a few millimeters. So, in instrument designs there are usually no UV hazards to be considered. Little gaps and holes don't cause a problem. However, you should take care in the instrument design that no UV degradable materials like polymers are in the proximity (< 5 mm) of the MgF2 window, since they may suffer under UV irradiation. The emitted UV intensity can be measured by appropriate calibrated UV meters. However, these devices are rather expensive, so it is the cheaper option to enclose the UV lamp into a housing that no UV light can escape. If you have any further questions please don't hesitate to contact me. Best regards, ------ -----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of Oglesbee, Robert A Sent: Tuesday, August 06, 2013 1:59 PM To: [email protected] Subject: RE: [PSES] Krypton Photoionisation Detector Lamps Depending on the lamp and setup they also produce enough ozone that you need to use them in a well-ventilated space... Rob Oglesbee (765) 494-5234 Senior Instrumentation Specialist Jonathan Amy Facility for Chemical Instrumentation -----Original Message----- From: John Woodgate [mailto:[email protected]] Sent: Tuesday, August 06, 2013 11:53 AM To: [email protected] Subject: Re: [PSES] Krypton Photoionisation Detector Lamps In message <64D32EE8B9CBDD44963ACB076A5F6ABB0265F7F9@Mailbox-Tech.lecotech.local>, dated Tue, 6 Aug 2013, "Kunde, Brian" <[email protected]> writes: >We are looking at using a Krypton Photoionisation Detector Lamp with >one of our products. It produces short wavelength Ultraviolet light >used to ionize molecules. These low power lamps produce 10eV at 123.0nm >and 10.6eV at 116.9nm. That's at the hot end of the UV-C band. It will make your teeth fluoresce. > >My question is regarding safety. I have found many many documents and >data sheets on the internet but none mention any safety precautions or >concerns with their use. Are the UV levels so low and/or at a >wavelength that they pose no hazards to human skin or to the eye? No, not at all. There is a serious safety issue. Wikipedia is your friend: http://en.wikipedia.org/wiki/Ultraviolet You have to scroll down to 'Harmful effects'. No doubt the regulatory requirements are different in different countries. - ---------------------------------------------------------------- This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list. To post a message to the list, send your e-mail to <[email protected]> All emc-pstc postings are archived and searchable on the web at: http://www.ieee-pses.org/emc-pstc.html Attachments are not permitted but the IEEE PSES Online Communities site at http://product-compliance.oc.ieee.org/ can be used for graphics (in well-used formats), large files, etc. Website: http://www.ieee-pses.org/ Instructions: http://listserv.ieee.org/request/user-guide.html List rules: http://www.ieee-pses.org/listrules.html For help, send mail to the list administrators: Scott Douglas <[email protected]> Mike Cantwell <[email protected]> For policy questions, send mail to: Jim Bacher: <[email protected]> David Heald: <[email protected]> ________________________________ LECO Corporation Notice: This communication may contain confidential information intended for the named recipient(s) only. If you received this by mistake, please destroy it and notify us of the error. Thank you. - ---------------------------------------------------------------- This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list. To post a message to the list, send your e-mail to <[email protected]> All emc-pstc postings are archived and searchable on the web at: http://www.ieee-pses.org/emc-pstc.html Attachments are not permitted but the IEEE PSES Online Communities site at http://product-compliance.oc.ieee.org/ can be used for graphics (in well-used formats), large files, etc. Website: http://www.ieee-pses.org/ Instructions: http://listserv.ieee.org/request/user-guide.html List rules: http://www.ieee-pses.org/listrules.html For help, send mail to the list administrators: Scott Douglas <[email protected]> Mike Cantwell <[email protected]> For policy questions, send mail to: Jim Bacher: <[email protected]> David Heald: <[email protected]>
