The Ontario Building Code | Ergonomic Design
9.8.7.5. Ergonomic design
(1) A clearance of not less than 50 mm shall be provided between a handrail and any surface behind it.
(2) All handrails shall be constructed so as to be continually graspable along their entire length with no obstruction on or above them to break a handhold, except where the handrail is interrupted by newels at changes in direction.