# Thread: Mistaken meaning of sentance

1. ## Mistaken meaning of sentance

Hello,

Help

'Exposed conductive parts are considered not to constitute a danger if they cannot be touched on large areas or grasped with the hand or if are of small size (approximately 50 x 50) or are so located as to exclude any contact with live parts.'
Question: do you need all of or any one of these points to say there is no constituted danger?

He has applied pure logic to this and says any one point being true/good means it is safe.
I argue it does not, you need all of them to be true.

2. ## Re: Mistaken meaning of sentance

I think the intention is clear, but the wording is unnecessarily double negative.

It is safe unless a large area can be touched, it can be grasped or the size is greater than 50 x 50. Then any one of the conditions (a logical or) clearly makes it unsafe.

3. ## Re: Mistaken meaning of sentance

Originally Posted by SoothingDave
Logic works. "Or" doesn't mean "and." It is a danger if any of these conditions are not met.

Not sure what is meant by "touched on large area." Doesn't the size of 50 x 50 specify what is the definition of the area?

EDIT: I think the intention is clear, but the wording is unnecessarily double negative.
Thank you SoothingDave,
the paragraph before this talks of 'exposed conductive parts (e.g. chassis, framework and fixed parts of metal enclosures)'
so they are refering to large items on equipment, but I do find it strange to make both large statement and separately define what is small.

My colleague refers to the OR logic of a binary circuit = that any of these being positive means it is safe.
I tried to explain against this but failed. I read as you that any one being negative = danger.

Thank you

#### Posting Permissions

• You may not post new threads
• You may not post replies
• You may not post attachments
• You may not edit your posts
•