Inflator assembly

Apparatus for use in inflating an inflatable vehicle occupant restraint, said apparatus comprising:

• gas generating means for generating gas to inflate the inflatable vehicle occupant restraint, said gas generating means including a body of gas generating material which, when ignited, generates said gas, said body of gas generating material having an initial surface portion;
• and
• igniter means for igniting said body of gas generating material, said igniter means being actuatable in a first stage and in a second stage;
• said igniter means igniting said body of gas generating material at a first ignitable surface area of said body of gas generating material when said igniter means is actuated in said first stage, said first ignitable surface area including said initial surface portion of said body of gas generating material;
• said igniter means including means for forming cracks in said body of ignitable gas generating material when said igniter means is actuated in said second stage, said cracks containing newly exposed surface portions of said body of gas generating material;
• said igniter means igniting said body of gas generating material at a second ignitable surface area of said body of gas generating material when said igniter means is actuated in said second stage, said second ignitable surface area including said initial surface portion, said second ignitable surface area further including said newly exposed surface portions and thus being larger than said first ignitable surface area.