New security regulations take effect on Monday, allowing passengers on most Canadian and international flights to carry some small knives.

Transport Canada says knife blades up to six centimetres, about the size of a large paper clip, will be allowed on domestic and most international flights.

But on U.S. bound flights, blades of any length are still prohibited, as are razor blades and box cutters of any size.

Another change that goes into effect on Monday will ban certain powders and granular material with a volume of 350 millilitres or more.

Those prohibited materials include baby powder, cooking powder, and bath salts.

Transport Canada says these adjustments reflect the changes in the security environment and are needed to harmonize with international standards.

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