Section 299.301 - Restoration or renewal of track under traffic conditions(a) Restoration or renewal of track, other than in yards and trainset maintenance facilities, under traffic conditions is prohibited.(b) Restoration or renewal of track under traffic conditions on track Class H2 in trainset maintenance facilities is limited to the replacement of worn, broken, or missing components or fastenings that do not affect the safe passage of trainset.(c) The following activities are expressly prohibited on track Class H2 in trainset maintenance facilities under traffic conditions:(1) Any work that interrupts rail continuity, e.g., as in joint bar replacement or rail replacement;(2) Any work that adversely affects the lateral or vertical stability of the track with the exception of spot tamping an isolated condition where not more than 4.5 m (15 feet) of track are involved at any one time and the ambient air temperature is not above 35 °C (95 °F); and(3) Removal and replacement of the rail fastenings on more than one tie at a time within 4.5 m (15 feet).