I'm not sure about the procedures at your particular home base, but in most cases LVOs will be in force if the visibility is below 550m. At AMS for example, below 1500m RVR is the first stage of LVO procedure.
However your procedures should be in OPS B.
Ours states:
"Relevant Runway Visual Range: Take-off: RVR for that part of the runway used to accelerate to V1 followed by a rejected takeoff and deceleration down to a speed of approximately 60 knots."
OPS B also gives a table of required RVR for Takeoff under different circumstances. Without LVOs in force, the minimum for us is 150m (with some other conditions met).