Seesaw a "teeter-totter". According to linguist Peter Trudgill, the term originates from the Nordic language word "tittermatorter". A "teeter-totter" may also refer to a two-person swing on a swing seat, on which two children sit facing each other and the teeter-totter swings back and forth in a pendulum motion. Both "teeter-totter" (from "teeter", as in "to teeter on the edge") and "seesaw" (from the verb "saw") demonstrate the linguistic process called reduplication, where a word or syllable is doubled, often with a different vowel. Reduplication is typical of words that indicate repeated activity, such as riding up and down on a
Playground Listing of Trained Playground Safety Inspectors is available for many states. A Certified Playground Safety Inspector (CPSI) is a career that was developed by the National Playground Safety Institute (NPSI) and is recognized nationally by the National Recreation and Park Association or N.R.P.A. (Some information sources offer interactive examples of playground equipment that violates CPSC guidelines.) In Australia, Standards Australia is responsible for the publication of the playground safety Standards AS/NS4422, AS/NZS4486.1 and AS4685 Parts 1 to 6. The University of Technology Sydney is responsible for the training and accreditation of playground inspectors. The Register of Playground Inspectors Australia lists