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| Glen Kramer <glen.kramer@TEKNOVUS.COM>
11/07/2006 05:37 PM
|
|
Glen,
IEC 60825-1 is titled “Safety of laser products - Part 1: Equipment classification requirements and user’s guide”
and IEC 60825-2 is titled “Safety of laser products – Part 2: Safety of optical fibre communication systems (OFCS)”
IEC 60825-1 is completely general covering all kinds of laser safety and IEC 60825-2 is specific to optical fibre based systems.
Each of these standards has various editions e.g. IEC 60825-2 Third edition 2004-06
I believe that the various editions of the IEC standards may be adopted by different countries at different times.
The power level quoted in the slide from Steve Swanson of Corning (+21.3 dBm at 1550 nm) is the class 1M limit for singlemode fibre with a mode field diameter of 11 um from IEC 60825-2 Third edition 2004-06
The definition of the various locations is:
controlled location
an accessible location where an engineering or administrative control is present to make it inaccessible, except to authorized personnel with appropriate laser safety training
restricted location
an accessible location that is normally inaccessible by the general public by means of any administrative or engineering control measure but that is accessible to authorized personnel who may not have laser safety training
unrestricted location
an accessible location where there are no measures restricting access to members of the general public
So a home would be an unrestricted location and I think that unless access to the connector is prevented, then the requirement is class 1 for the wavelengths of interest.
A CO is generally taken to be a restricted location where the requirement is class 1M for the wavelengths of interest.
Pete Anslow
Nortel Networks UK Limited, London Rd, Harlow, Essex CM17 9NA, UK
External +44 1279 402540 Fax +44 1279 405670 ESN 742 2540
Email: pja@nortel.com
_____________________________________________
From: Glen Kramer [mailto:glen.kramer@teknovus.com]
Sent: 07 November 2006 22:00
To: STDS-802-3-10GEPON@listserv.ieee.org
Subject: Re: [8023-10GEPON] FW: [8023-10GEPON] 10GEPON ad hoc on higher
split ratio - Conference Call Minutes
Dear Takahashi-san,
Does this mean that higher power levels allowed by IEC 60825 are not allowed in Japan?
This is a question for all: should we limit ourselves to 60825-1 to make it a more universally applicable spec, or should we follow the latest amendments that allow higher power levels, even though it may put it above the limit in some countries?
I am curious what norms and regulations exist in other countries. Please, comment if you have this info.
IEEE 802.3ah has referred to 60825-1, even though at the time of 802.3ah approval (2004), the 60825-2 already existed.
Note: It may turn out that the effects of channel non-linearities put much more stringent limits on launch power, so the question of which safety standard to follow may not be critical. Our high-split ratio ad hoc should answer this question.
Glen
> -----Original Message-----
> From: Akira Takahashi
> [mailto:Takahashi.Akira@AJ.MITSUBISHIELECTRIC.CO.JP]
> Sent: Tuesday, November 07, 2006 8:09 AM
> To: STDS-802-3-10GEPON@listserv.ieee.org
> Subject: Re: [8023-10GEPON] FW: [8023-10GEPON] 10GEPON ad hoc on
> higher split ratio - Conference Call Minutes
>
> Dear all,
>
> The class of laser is standardized in each country, it is standardized
> in JIS(Japanese Industrial Standards) JISC6803 in Japan, and IEC
> 60825-1 is the base.
> In ad hoc on wavelength and co-existence, 1210nm and 1580nm are also
> discussed as the candidates. In Table 1 of IEC 60825-1, the output of
> the laser limited with Class 1 is as follows,
>
> 1210nm 15.6mW(+12dBm)
> 1310nm 15.6mW(+12dBm)
> 1420nm 10mW(+10dBm)
> 1490nm 10mW(+10dBm)
> 1550nm 10mW(+10dBm)
> 1580nm 10nm(+10dBm)
>
> Regards,
>
> Takahashi
>
> MITSUBISHI ELECTRIC CORPORATION
>
>
> ----- Original Message -----
> From: Pete Anslow
> To: STDS-802-3-10GEPON@listserv.ieee.org
> Sent: Thursday, November 02, 2006 7:36 AM
> Subject: Re: [8023-10GEPON] FW: [8023-10GEPON] 10GEPON ad hoc on
> higher split ratio - Conference Call Minutes
>
>
>
> Glen,
>
>
>
> You asked ? "Can we somehow translate the 60825 requirements into a
> maximum limit for launch power at ONU?"
>
>
>
> The answer is that to do this properly you have to apply all of the
> rules found in IEC 60825-1 and 60825-2 and the maximum power you get
> depends on wavelength. However, Table D.1 of IEC 60825-2 contains the
> limits for 11 um mode field diameter single mode fibre for the following wavelengths:
>
>
>
> 1310 nm 15.6 mW (+12 dBm)
>
> 1420 nm 10 mW (+10 dBm)
>
> 1550 nm 10 mW (+10 dBm)
>
>
>
>
>
> "is it reasonable to anticipate that a customer sooner or later will
> decide to look directly into the ONU connector?"
>
> I think that the answer to that is definitely "Yes"
>
>
>
> "Is it reasonable that a customer will try to pry open a shutter door
> that a connector may have."
>
> I think that this is much more difficult to answer and may be affected
> by how difficult it is to do etc.
>
>
>
> "Is the ONU's mode of operation when it shuts down its laser when it
> sees no incoming signal a reasonable measure to classify higher-power
> optics as class 1?"
>
> I think that the correct terminology for equipment that operates at
> high power levels and automatically shuts down in the event of loss of
> continuity of the link is that it is Hazard level 1.
>
> The answer to whether an ONU is Hazard level 1 because of a shutdown
> mechanism depends on things like the time between the loss of
> continuity of the link and the power reduction (I think that this must
> be < 1 second for unrestricted locations) and the reliability of the
> shutdown mechanism (e.g.
> software based shutdown may not be reliable enough).
>
> This is a complex subject ? see IEC 60825-2 for details.
>
>
>
> IEC 60825-2 also contains information specific to PONs. For example
> clause D.4.6
>
>
>
> Regards,
>
> Pete Anslow
>
>
>
> Nortel Networks UK Limited, London Rd, Harlow, Essex CM17 9NA, UK
>
> External +44 1279 402540 Fax +44 1279 405670 ESN 742 2540
>
>
>
> Email: pja@nortel.com
>
>
>
>
> ----------------------------------------------------------------------
> ----
> ------
>
> From: Glen Kramer [mailto:glen.kramer@teknovus.com]
> Sent: 01 November 2006 20:51
> To: STDS-802-3-10GEPON@listserv.ieee.org
> Subject: Re: [8023-10GEPON] FW: [8023-10GEPON] 10GEPON ad hoc on
> higher split ratio - Conference Call Minutes
>
>
>
> > Class 4 lasers are of high power . may have sufficient energy to
> ignite materials .
>
>
>
> That's what I need! Now we are talking business.
>
>
>
>
>
> Seriously, our RAP stated that our project won't "result in any
> health, safety, security, or environmental guidance that affects or
> applies to human health or safety". For 1G EPON, clause 60 explicitly
> limits us to class I optics and it explicitly refers to IEC 60825:
>
>
>
> 60.8.2 Laser safety
>
> 1000BASE-PX10 and 1000BASE-PX20 optical transceivers shall conform to
> Class 1 laser requirements as
>
> defined in IEC 60825-1, under any condition of operation. This
> includes single fault conditions whether
>
> coupled into a fiber or out of an open bore. Conformance to additional
> laser safety standards may be
>
> required for operation within specific geographic regions.
>
>
>
>
>
> I am not very clear how to interpret the Class I rules below:
>
>
>
> A class 1 laser is safe for use under all reasonably-anticipated
> conditions of use; in other words, it is not expected that the maximum
> permissible exposure (MPE) can be exceeded. This class may include
> lasers of a higher class whose beams are confined within a suitable
> enclosure so that access to laser radiation is physically prevented.
>
>
>
> What are all reasonably-anticipated conditions and what is expected MPE?
> For example, is it reasonable to anticipate that a customer sooner or
> later will decide to look directly into the ONU connector? Is it
> reasonable that a customer will try to pry open a shutter door that a
> connector may have.
>
>
>
> Is the ONU's mode of operation when it shuts down its laser when it
> sees no incoming signal a reasonable measure to classify higher-power
> optics as class 1? My point is that this protection (a useful
> side-effect of MPCP,
> really) is done at a protocol level, way above PMD.
>
>
>
> Can we somehow translate the 60825 requirements into a maximum limit
> for launch power at ONU?
>
>
>
> Glen
>
>
>
>
>
>
>
> Tom,
>
> Good data. I am not sure why you were not able to post. I am
> forwarding this to the reflector (phone and e-mail from you signature
> were removed to curb spam).
> Glen
>
>
> Glen, I tried posting to the listserv but I guess I've only got
> Lurking permissions. I have some awareness of laser safety as our
> test products use Lasers up to 20 mw or so:
> As one might expect Laser Safety is not a simple issue. Requirements
> are generally concerned about optical power density (mw/cm^2). I
> would guess that an EDFA output at +20 dB (100 mW) could fall under class IIIB.
> Revised system
> In 2002 the system of Laser Classes was revised as part of a revision
> of the international laser safety standard, IEC 60825. The revision
> was based on the greater knowledge of lasers that had accumulated
> since the original classification system was devised, and was intended
> to permit certain types of lasers to be recognized as having a lower
> hazard than was implied by their placement in the original
> classification system. The revised system is expected to be adopted
> for use in the US in the next revision of the ANSI Laser Safety
> Standard (ANSI Z136). The FDA, which regulates lasers offered in
> commerce in the United States, does not object to its use on imported
> laser products' labels and markings.
>
> class I
>
> A class 1 laser is safe for use under all reasonably-anticipated
> conditions of use; in other words, it is not expected that the maximum
> permissible exposure (MPE) can be exceeded. This class may include
> lasers of a higher class whose beams are confined within a suitable
> enclosure so that access to laser radiation is physically prevented.
>
> class IM
>
> Class 1M lasers produce large-diameter beams, or beams that are divergent.
> The MPE for a Class 1M laser cannot normally be exceeded unless
> focusing or imaging optics are used to narrow down the beam. If the
> beam is refocused, the hazard of Class 1M lasers may be increased and
> the product class may be changed.
>
> class II
>
> A class 2 laser emits in the visible region. It is presumed that the
> human blink reflex will be sufficient to prevent damaging exposure,
> although prolonged viewing may be dangerous.
>
> class IIM
>
> A class IIM laser emits in the visible region in the form of a large
> diameter or divergent beam. It is presumed that the human blink reflex
> will be sufficient to prevent damaging exposure, but if the beam is
> focused down, damaging levels of radiation may be reached and may lead
> to a reclassification of the laser.
>
> class IIIR
>
> A class 3R laser is a continuous wave laser which may produce up to
> five times the emission limit for Class 1 or class 2 lasers. Although
> the MPE can be exceeded, the risk of injury is low. The laser can
> produce no more than
> 5 mW in the visible region.
>
> class IIIB
>
> A class 3B laser produces light of an intensity such that the MPE for
> eye exposure may be exceeded and direct viewing of the beam is
> potentially serious. Diffuse radiation (i.e., that which is scattered
> from a diffusing
> surface) should not be hazardous. CW emission from such lasers at
> wavelengths above 315 nm must not exceed 0.5 watts.
>
> class IV
>
> Class 4 lasers are of high power (typically more than 500 mW if cw, or
> 10
> J/cm2 if pulsed). These are hazardous to view at all times, may cause
> devastating and permanent eye damage, may have sufficient energy to
> ignite materials, and may cause significant skin damage. Exposure of
> the eye or skin to both the direct laser beam and to scattered beams,
> even those produced by reflection from diffusing surfaces, must be
> avoided at all times. In addition, they may pose a fire risk and may
> generate hazardous fumes.
>
> (From The Physical and Theoretical Chemistry Laboratory Oxford
> University)[7]
>
>
>
>
>
>
>
> Tom Durston
>
> Product Development Manager
>
> Greenlee / Textron
>
>
>
>
>
>
>
>
> ----------------------------------------------------------------------
> ----
> ------
>
> From: Glen Kramer [mailto:glen.kramer@TEKNOVUS.COM]
> Sent: Wednesday, November 01, 2006 1:21 PM
> To: STDS-802-3-10GEPON@listserv.ieee.org
> Subject: Re: [8023-10GEPON] 10GEPON ad hoc on higher split ratio -
> Conference Call Minutes
>
>
>
> David,
>
>
>
> What about upstream launch power? I am not sure, but I'd guess the
> safety rules would be different for CO and for a household.
>
>
>
> Are there any volunteers to make a short overview presentation on the
> topic?
>
>
>
> Glen
>
>
>
>
> ----------------------------------------------------------------------
> ----
> ------
>
> From: David Piehler [mailto:dpiehler@ALPHION.COM]
> Sent: Wednesday, November 01, 2006 6:55 AM
> To: STDS-802-3-10GEPON@listserv.ieee.org
> Subject: Re: [8023-10GEPON] 10GEPON ad hoc on higher split ratio -
> Conference Call Minutes
>
>
>
> I don't know the exact safety issues involved, but I do know that
> carriers deploying the video overlay do launch up to +20 dBm at 1550
> nm into the OSP fiber. Also in the CATV world, this type of launch
> power is not uncommon.
>
>
>
> David Piehler
>
> Alphion
>
> mobile: +1 732 692 4581
>
>
> ----------------------------------------------------------------------
> ----
> ------
>
> From: Glen Kramer [mailto:glen.kramer@teknovus.com]
> Sent: Tuesday, October 31, 2006 11:49 AM
> To: STDS-802-3-10GEPON@listserv.ieee.org
> Subject: Re: [8023-10GEPON] 10GEPON ad hoc on higher split ratio -
> Conference Call Minutes
>
>
>
> Mike,
>
>
>
> This is a great point. Could you provide some more info on class 1 safety?
> In general, what regulations apply to CPE side and to CO side? It
> would be great to have a presentation in November covering this topic.
> It definitely should be part of the set of constraints that the
> high-split ad hoc considers.
>
>
>
> Glen
>
>
>
>
> ----------------------------------------------------------------------
> ----
> ------
>
> From: Mike Dudek [mailto:mike.dudek@PICOLIGHT.COM]
> Sent: Tuesday, October 31, 2006 11:35 AM
> To: STDS-802-3-10GEPON@listserv.ieee.org
> Subject: Re: [8023-10GEPON] 10GEPON ad hoc on higher split ratio -
> Conference Call Minutes
>
>
>
> Dear all,
>
>
>
> One question related to the higher split ratio that I haven't seen
> discussed is related to laser eye safety. Is this a problem for EPON?
> For other
> ethernet standards we've normally required class 1 eye safety. I think
> powers significantly higher than this are being considered here.
>
>
>
> Regards,
>
> Mike Dudek
> Director Transceiver Engineering
> Picolight Inc
> 1480 Arthur Avenue
> Louisville
> CO 80027
> Tel 303 530 3189 x7533.
> mike.dudek@picolight.com
>
>
> ----------------------------------------------------------------------
> ----
> ------
>
> From: Hajduczenia, Marek [mailto:marek.hajduczenia@SIEMENS.COM]
> Sent: Tuesday, October 31, 2006 1:06 AM
> To: STDS-802-3-10GEPON@listserv.ieee.org
> Subject: [8023-10GEPON] 10GEPON ad hoc on higher split ratio -
> Conference Call Minutes
>
> Dear all,
>
>
>
> below please find the conference call minutes, taken down by Glen
> (thank You for the job well done)
>
>
>
> please let me know if You find any irregularities in the minutes or if
> You have any comments on those.
>
>
>
> **********************************************************************
> ****
> *****
>
>
>
> Attendees:
>
> Haim Ben-Amram
>
> Russell Davey
>
> Glen Kramer
>
> Marek Hajduczenia
>
> Frank Chang
>
> Silvia Pato
>
> David Piehler
>
> Harold Kamisugi
>
> Bin Yeong Yoon
>
> Dong Soo Lee
>
> Wael Diab
>
>
>
> Task 1: estimation of 1x64 and 1x128 port splitter power loss values
>
> ---------------------------------------------------------------------
>
> Discussed Marek's presentation. Few questions about derivation of
> splitter loss. No objections. Task 1 is considered completed.
>
>
>
> Task 2: non-linear effects in fiber channel
>
> -------------------------------------------
>
> Silvia gave brief overview of the paper on non-liner effects in 10GEPON.
> SBS seems like major impairment. Mentioned dithering technique for
> laser sources.
>
> Questions that need more research:
>
> 1) Can video-overlay even be supported on 1x128 PON? What power budget
> will be required?
>
> 2) Can we use high-power source for data wavelength and use video-overlay?
> Effects of Raman crosstalk due to high-power source.
>
> AR: Silvia will finish sub-task 2.2 "estimate the maximum launch power
> into fiber which can be achieved without introducing non-linear effects"
> by
> November 6th.
>
>
>
> Task 3: TX/RX technology
>
> ----------------------
>
> Bin Yeong Yoon and dong Soo Lee are in the process of compiling a
> survey of receivers, transmitters, and amplifiers available on the market today.
>
> AR: Bin Yeong Yoon is to finish the first draft later this week. Then
> narrow down the viable configurations based on input from task 2.
>
>
>
> Task 4: power margins in the EPON systems
>
> -----------------------------------------
>
> It seemed to be difficult to get this data from carriers. It was
> decided that for now we will reverse-calculate this data from
> insertion loss taken in 802.3ah. We later may update it with more
> accurate numbers based on carriers' responses to a wavelength/power
> survey.
>
> AR: Marek is to calculate allocation for penalties and outside plant
> aging and repair margins later this week.
>
> An additional conference call may be scheduled to discuss final drafts
> of the presentations.
>
>
>
> **********************************************************************
> ****
> *****
>
>
>
> Best wishes
>
>
>
> Marek Hajduczenia (141238)
> (PhD Student - COM RD1)
> SIEMENS Networks S.A. - IC
> Rua Irmaos Siemens, 1
> Ed. 1, Piso 1
> Alfragide
> 2720-093 Amadora
> Portugal
> * Marek.Hajduczenia@siemens.com
> http://marekhaj.easyisp.pl/index.php
> (+351.21.416.7472 4+351.21.424.2082
>
>
>
>
>