Flammability Ratings for Internal Battery & Hand-Held ME Equipment

[bennylee]

Hello, All,

Our company currently concern on the flammability ratings for EU & USA (including Canada)

From IEC 60601-1 section 11.3 Constructional requirements for fire ENCLOSURES, we found that

A) Enclosure ( for TRANSPORTABLE ME) need V-2 or above
B) PCB need V-2 or above
C) Internal wire need V-1 or above​

As our device is small, internally battery & hand-held ME equipment, it will not have any risk to cause fire when in use.

1) may we know if the above requirements for fire ENCLOSURES must apply?
2) Any different requirement for EU & USA ?​

Thanks in advance!

 

[J0anne]

1- Analyse this in your risk management file and either meet this requirement or justify why you are not meeting this requirement

2 - 60601 certification is acceptable for marketing medical devices in the US

 

[bennylee]

Hello Joanne, Thanks for your information !

Actually, flammability ratings for some of enclosure is 94HB, which is lower standard than V-2, hence, we will need to do some risk analysis for this point.

As our test is applied to en60601-1 3rd version, in the test report from test firm, already shown enclosure is 94HB, i think it will be fine for EN market (with related risk analysis)

For or USA, I search some information from test firm, it seems that flammability ratings must follow ul, it will be more tough than EN standard, I still not very clear about this, may I know if anyone can share more information about this?

Thanks in advance !

 

[bennylee]

I have checked information (it posted on February 1, 2004) from mddionline.com

It stated that "If the fire enclosure is sourced by circuits limited to less than 15 W, flammability requirements are not required." , may I know if this sentence is still effective for medical device.

 

[Pads38]

Fire enclosures are, generally, only required where there is a significant likelihood of fire due to the presence of a source of ignition and a significant source of fuel.

Most materials used in devices do not represent a significant source of fuel unless they are used in an oxygen rich atmosphere.

Ignition sources are those that are capable of releasing more than 900 Joules.

The 15W exemption applies to the single fault conditions of clause 13.1.2. So, if you can show that, during a fault condition, your circuit cannot provide more than 15w of power then you do not need to consider clause 13.1.2.

References:
Clause 11.3 (and rationale)
Clause 13.1.2 (and rationale)
Interpretation Sheet 2, I-SH 02, IEC January 2009.
(I would have posted a link to that but the IEC web site is not working properly at the moment).

Edit:
Link to the Interpretation Sheet:
http://webstore.iec.ch/webstore/webstore.nsf/artnum/042566!opendocument

 

[Peter Selvey]

Just a note that the 1st amendment to IEC 60601-1:2005 has lifted the power limit to 100VA (in normal and fault condition) for parts under 60Vdc, provided that the PCB is FV-1 and the "wire insulation of types PVC, TFE, PTFE, FEP, polychloroprene or polybromide".

That will be a big help as there are a lot of secondary circuits and battery operated devices which are >15W but less than 100VA. PCBs with FV-1 rating and allowable wiring types are readily available.

 

[John Alleman]

Any idea why wire insulation of types PVC, TFE, PTFE, FEP, polychloroprene or polybromide were specified?