Below is a link to NHS Direct which outlines how to deal with vomiting and other sicknesses in babies aged 0-12 months and gives a detailed questionaire giving you steps to follow in case of an emergency:
http://www.nhs.uk/conditions/vomiting-children-babies/Pages/Introduction.aspx
The below link is for children aged 1 - 4 years:
http://www.nhsdirect.nhs.uk/help/bodykey/Questions/Index.aspx?nodes=p7ytNCKhPGg%3d
The below link is for children aged 5 - 17 years:
http://www.nhsdirect.nhs.uk/help/bodykey/questions/index.aspx?nodes=6A%2b9deGMdpc%3d
For information on those who are vomiting at ages 18 and over please see the following link for adults:
http://www.nhsdirect.nhs.uk/help/bodykey/questions/index.aspx?nodes=T8OeHjqIvz4%3d