Selection of Treatment Areas: Determine areas where rats and/or house mice will most likely find and consume bait. Generally, these are along walls, by gnawed openings, in corners and concealedplaces, between floors or walls, beside burrows, or in locations where rats and/or house mice or their signs have been observed. Remove as much alternative food as possible. 
House Mice: Apply 1 block per placement, usually spaced 8-12 ft apart.  Up to 2 blocks may be needed at point of very high mouse activity.  Maintain a contstant supply of fresh bait for 15 days or until signs of house mouse activity cease. 
Rats: apply 3-6 blocks per placement, usually spaced 15-30 ft apart.  Maintain constant supply of fresh bait for 10 days or until signs of rat activity cease. 

For sewer applications: securely attach one end of the wire to block of bait and the other end to a stationary structure, such as the bottom step of manhole ladder or to a sewer grate, allowing just enough wire for bait to rest on manhole benching. If benching is not present, suspend bait a few inches above the high water line or place bait on a board supported by opposing steps of the ladder. Securing bait in this manner will minimize chance for removal by rats or water. Place at least 16 blocks per manhole.
Follow-up: Replace contaminated or spoiled bait immediately. Wearing waterproof gloves, collect and dispose of all visible dead animals and leftover bait, as well as any bait that has become accessible to non-target animals. To discourage reinfestation, limit sources of rodent food, water and harborage as much as possible. If reinfestation does occur, repeat treatment. For a continuous infestation, set up permanent bait stations and replenish bait as needed.