Does a Flat, Sharp, or Natural Sign Last the Whole Measure?

In a measure, if the flat, sharp, or neutral symbol is for just a note, is it just for that note in the measure, or for every letter? This might be confusing so I made an example. Pretend the B is on the middle line for clef. It has a neutral/sharp/flat sign next to it. Is it just for that note, or does the notes that come after it count too? and does it count for all the B's on the other lines?

ANSWER

The "accidental" (a sharp, flat or natural not in the key sig nature)applies to all notes in the measure which are on the same staff position.


Lynne