If you are authorized to work or study in Canada, your accompanying family members may also be able to work here by virtue of the permit you are issued. No other authorization is required. Open work permits allow them to work in any job with any employer. An open work permit also means that they may be hired without the employer having to obtain a Labour Market Opinion (the normal authorization required).
Accompanying family members’ work permits will be valid for no longer than the duration of your own work permit.