When the browser will see that header, the page will be refreshed after 1 second. I won't say every 1 seconds as the next time it is up to the servlet to add that header or not. See more details on this page...
Looking through the RFC 2616 for HTTP1.1 I dont see a "refresh" header defined for responses so this would depend on non standard browser behavior. See the link Ankit gave for the Meta alternative.
Bill