Re: SAR Measurements
The FCC has said they would issue a more explicit OET 65 covering RF exposure around the end of this year. Until that time you may find that the FCC guidance to TCBs offers many clues as to the FCC methods. You can find the document at http://www.curtis-straus.com/exclusionlist.pdf In it, 2.4GHz portable devices less than 15mW are allowed to be approved by TCBs without SAR testing, even if they are against the human body. Higher powers are also allowed without SAR depending on the distance from the body and extremities. Jon Curtis. umbdenst...@sensormatic.com wrote: Lothar, The FCC uses an unusual splitting of hairs regarding categorically excluded. This means you are not required to do the SAR measurement or analysis; but, you must still prove compliance by methods such as identifying the radiated power and establishing the separation distance of John Q Public from the radiating element. The requirements vary according to whether the product is fixed external (e.g. roof mounted), fixed internal (inside a facility where persons are likely to be in proximity), mobile (antenna separate from electronics), or portable (i.e., in intimate contact with the body). These differences are crucial in determining whether one can apply MPE formulas or whether SAR needs to be addressed. There must be a magic threshold as TCBs are allowed to approve some devices (I would interpret that to mean no exposure risk) but not others. TCBs are allowed to approve devices that meet certain requirements such as power output threshold and radiator set backs for 15.247, but I do not have the URL on which the TCB rules list is located. I assume that the ISM band must have something similar. Curtis-Strauss is well versed in TCB issues. I would suspect that they would have knowledge of the limitations if any TCB did. If you wish to go straight to the source for exposure issues, that would be a Mr. Kwok Chan at the FCC. I know this did not answer your question directly, but I hope it helped. Don Umbdenstock -- From: Wismer, Sam[SMTP:wisme...@lxe.com] Reply To: Wismer, Sam Sent: Friday, October 20, 2000 2:30 PM To: Lothar Schmidt; EMC-PSTC (E-mail) Subject: RE: SAR Measurements Lothar, As you already know I'm sure, part 15 devices are categorically excluded from routine environmental evaluation. But that doesn't stop the FCC from hounding you about it everytime you send up an application. I routinely get a request from the FCC of how I comply with section 15.247(b)(4) which is about the most vague section in the book. However, after following all the refer to's, section 2.1093(c) that states part 15 devices(not all, but most), are categorically excluded. After many debates with the FCC, what I have come to realize is that, although part 15 devices are categorically excluded, the FCC reserves the right to mandate an applicant to show compliance to the SAR requirements and perform the measurements. To answer your question about where it is written that any device less than 1mW is exempt, I haven't seen such a document, but I have been told that the FCC has an unwritten threshold of about 200mW for ISM equipment and will not require testing. Our ISM radios, which are up to 100mW, have never been required by the FCC to submit to SAR evaluation. In my applications, I provide MPE calculations for our Mobile equipment and for our portable equipment I simply cite section 2.1093 and reference OET Bulletin 65, Supplement C. However, if your market includes Canada, all this is now moot since RSS 102 includes ISM devices and you have to do the test anyway. ~ Sam Wismer Lead Regulatory Engineer/ Radio Approvals Engineer LXE, Inc. (770) 447-4224 Ext. 3654 Visit Our Website at: http://www.lxe.com http://www.lxe.com/ -Original Message- From: Lothar Schmidt [mailto:lothar.schm...@cetecomusa.com] Sent: Friday, October 20, 2000 12:01 PM To: EMC-PSTC (E-mail) Subject: SAR Measurements Hi group, Does anybody know a source where is written that a portable device (spread spectrum in the 24 gHz range) under OET 65 has not to be measured regarding SAR if the radiated power is less than 1 mW (0 dBm)? Or is this only the experience that these kind of devices never exeed the limits of table 2? Any hint welcome Thanks Best Regards Lothar Schmidt Technical Manager EMC/Bluetooth, BQB, Competent Body Cetecom Inc. 411 Dixon Landing Road Milpitas, CA 95035 Phone: +1 (408) 586 6214 Fax: +1 (408) 586 6299 --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc
RE: SAR Measurements
Lothar, The FCC uses an unusual splitting of hairs regarding categorically excluded. This means you are not required to do the SAR measurement or analysis; but, you must still prove compliance by methods such as identifying the radiated power and establishing the separation distance of John Q Public from the radiating element. The requirements vary according to whether the product is fixed external (e.g. roof mounted), fixed internal (inside a facility where persons are likely to be in proximity), mobile (antenna separate from electronics), or portable (i.e., in intimate contact with the body). These differences are crucial in determining whether one can apply MPE formulas or whether SAR needs to be addressed. There must be a magic threshold as TCBs are allowed to approve some devices (I would interpret that to mean no exposure risk) but not others. TCBs are allowed to approve devices that meet certain requirements such as power output threshold and radiator set backs for 15.247, but I do not have the URL on which the TCB rules list is located. I assume that the ISM band must have something similar. Curtis-Strauss is well versed in TCB issues. I would suspect that they would have knowledge of the limitations if any TCB did. If you wish to go straight to the source for exposure issues, that would be a Mr. Kwok Chan at the FCC. I know this did not answer your question directly, but I hope it helped. Don Umbdenstock -- From: Wismer, Sam[SMTP:wisme...@lxe.com] Reply To: Wismer, Sam Sent: Friday, October 20, 2000 2:30 PM To: Lothar Schmidt; EMC-PSTC (E-mail) Subject: RE: SAR Measurements Lothar, As you already know I'm sure, part 15 devices are categorically excluded from routine environmental evaluation. But that doesn't stop the FCC from hounding you about it everytime you send up an application. I routinely get a request from the FCC of how I comply with section 15.247(b)(4) which is about the most vague section in the book. However, after following all the refer to's, section 2.1093(c) that states part 15 devices(not all, but most), are categorically excluded. After many debates with the FCC, what I have come to realize is that, although part 15 devices are categorically excluded, the FCC reserves the right to mandate an applicant to show compliance to the SAR requirements and perform the measurements. To answer your question about where it is written that any device less than 1mW is exempt, I haven't seen such a document, but I have been told that the FCC has an unwritten threshold of about 200mW for ISM equipment and will not require testing. Our ISM radios, which are up to 100mW, have never been required by the FCC to submit to SAR evaluation. In my applications, I provide MPE calculations for our Mobile equipment and for our portable equipment I simply cite section 2.1093 and reference OET Bulletin 65, Supplement C. However, if your market includes Canada, all this is now moot since RSS 102 includes ISM devices and you have to do the test anyway. ~ Sam Wismer Lead Regulatory Engineer/ Radio Approvals Engineer LXE, Inc. (770) 447-4224 Ext. 3654 Visit Our Website at: http://www.lxe.com http://www.lxe.com/ -Original Message- From: Lothar Schmidt [mailto:lothar.schm...@cetecomusa.com] Sent: Friday, October 20, 2000 12:01 PM To: EMC-PSTC (E-mail) Subject: SAR Measurements Hi group, Does anybody know a source where is written that a portable device (spread spectrum in the 24 gHz range) under OET 65 has not to be measured regarding SAR if the radiated power is less than 1 mW (0 dBm)? Or is this only the experience that these kind of devices never exeed the limits of table 2? Any hint welcome Thanks Best Regards Lothar Schmidt Technical Manager EMC/Bluetooth, BQB, Competent Body Cetecom Inc. 411 Dixon Landing Road Milpitas, CA 95035 Phone: +1 (408) 586 6214 Fax: +1 (408) 586 6299 --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Jim Bacher: jim_bac...@mail.monarch.com Michael Garretson:pstc_ad...@garretson.org For policy questions, send mail to: Richard Nute: ri...@ieee.org --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Jim Bacher: jim_bac...@mail.monarch.com Michael Garretson
RE: SAR Measurements
Lothar, As you already know I'm sure, part 15 devices are categorically excluded from routine environmental evaluation. But that doesn't stop the FCC from hounding you about it everytime you send up an application. I routinely get a request from the FCC of how I comply with section 15.247(b)(4) which is about the most vague section in the book. However, after following all the refer to's, section 2.1093(c) that states part 15 devices(not all, but most), are categorically excluded. After many debates with the FCC, what I have come to realize is that, although part 15 devices are categorically excluded, the FCC reserves the right to mandate an applicant to show compliance to the SAR requirements and perform the measurements. To answer your question about where it is written that any device less than 1mW is exempt, I haven't seen such a document, but I have been told that the FCC has an unwritten threshold of about 200mW for ISM equipment and will not require testing. Our ISM radios, which are up to 100mW, have never been required by the FCC to submit to SAR evaluation. In my applications, I provide MPE calculations for our Mobile equipment and for our portable equipment I simply cite section 2.1093 and reference OET Bulletin 65, Supplement C. However, if your market includes Canada, all this is now moot since RSS 102 includes ISM devices and you have to do the test anyway. ~ Sam Wismer Lead Regulatory Engineer/ Radio Approvals Engineer LXE, Inc. (770) 447-4224 Ext. 3654 Visit Our Website at: http://www.lxe.com http://www.lxe.com/ -Original Message- From: Lothar Schmidt [mailto:lothar.schm...@cetecomusa.com] Sent: Friday, October 20, 2000 12:01 PM To: EMC-PSTC (E-mail) Subject: SAR Measurements Hi group, Does anybody know a source where is written that a portable device (spread spectrum in the 24 gHz range) under OET 65 has not to be measured regarding SAR if the radiated power is less than 1 mW (0 dBm)? Or is this only the experience that these kind of devices never exeed the limits of table 2? Any hint welcome Thanks Best Regards Lothar Schmidt Technical Manager EMC/Bluetooth, BQB, Competent Body Cetecom Inc. 411 Dixon Landing Road Milpitas, CA 95035 Phone: +1 (408) 586 6214 Fax: +1 (408) 586 6299 --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Jim Bacher: jim_bac...@mail.monarch.com Michael Garretson:pstc_ad...@garretson.org For policy questions, send mail to: Richard Nute: ri...@ieee.org
