One-self-contained breathing apparatus (SCBA) limitation that the firefighter should be aware of is ________.
1) Occupational Safety and Health Administration prohibits spectacles in SCBA masks.
2) SCBA and personal protective equipment add approximately 60-70 pounds of weight to the firefighter.
3) The degree of training or experience users have with SCBA affects their level of self-confidence.
4) Low air alarms frequent malfunction.