Special VFR as per AIP.
By Day when VMC does not exist, the ATC unit responsible for a CTR may issue , at pilot request , a Special VFR clearance for flight in the CTR , or in the CTA next to the CTR for the purposes of entering or leaving the CTR , provided Special VFR will not unduly delay an IFR flight.
When your Operatig Special VFR you must ensure;
1.flight is conducted clear of cloud
2.viz is not less than : a. a/c 3000m b. Helo's 800m , c. Balloons 100m below 500ft agl , 3000m at or above 500ft agl.
3. The flight is conducted with regards to CAR 157 - Low Flying.
4. Special VFR is NOT allowed in Class E airspace.
Hoep that helps ... found in AIP ENR 1.2-1.
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