If the vehicle is equipped with a front passenger airbag switch), the airbag switch must be in the "ON" position in order for the seat belt pre-tensioners to be activated in the event of a vehicle collision.
Warning! Improper disposal of seat belt pretensioners or disposal of vehicles with the pretensioner system not deactivated is dangerous. Failure to take the necessary safety precautions may result in personal injury. For information on the safe disposal of pretensioners and vehicles equipped with the pretensioner system, contact an authorized Mazda dealer.
Seat belt pretensioners only activate when a frontal impact is severe enough (or close to the frontal) collision of the vehicle. Pretensioners, as a rule, do not deploy in rollovers, side impacts and rear impacts. When the air bags inflate and the seat belt pretensioners deploy, smoke is released, which is not toxic. The appearance of smoke does not indicate any fire. This gas does not usually have a harmful effect on the well-being of the passengers in the vehicle. However, people with sensitive skin may feel a slight irritation of the skin. If any particles or residue from the deployed air bags or pretensioners come into contact with the skin or eyes, immediately wash them off with water.
(Content based on information from: Mazbook)