material safety data sheet, n an informational form detailing the chemical and physical properties, hazards, and ways of safely handling a toxic chemical.
BRB means be right back. It is one of the most commonly used acronyms in online chat and texting. It communicates that the person is leaving for a moment, but will be back shortly.
  HB refers to the hardness of the pencil. In the scale H is used for harder pencils (H for hard) HH HHH HHHH all get progressively harder, and B (the B stands for black) â¦ BB BBB BBBB get progressively softer. HB pencils (#2 on the US pencil-hardness scale) are right in the middle, so the HB stands for Hard Black.f you mean what HB stands for, it's an indicator for the hardness (H) or softness (B) of the graphite and clay used. However, the B is for blackness so HB is like average/m â¦ edium grade so the full form would be Hard Black, Hard and Black, or Hard Blackness.