Finding and Verifying CAS Registry Numbers^® on STN^®
— March 1993 —

Appendix 6 — Costs of Searching Online

Here are some ideas to help you keep your online searching costs as low as possible. If you are not careful you can easily and quickly create a large bill without realizing it! Prices are published in the STN International Price List.

Be Aware of Online Fees:

1. Connect hour fees and telecommunication charges
2. Search term fees
3. Answer DISPLAY fees
4. EXPAND is free

Tips For Keeping Costs Low

1. It is helpful to have a phone line for a telephone and a separate phone line for your modem. Then you can call the STN Help Desk or someone else when you need help and still stay logged on. It can be easier to solve a problem if you have online information on the screen right in front of you.
2. Use the LREGISTRY File when you start learning how to use STN. Because you are only charged connect hour fees and telecommunication fees, this saves you money while you get comfortable with commands.
3. Follow “STEP 1 - PREPARE FIRST.” Get as much chemical substance information as you can before logging on. This will help you verify your answers. Have it readily available if you need to call someone to ask questions so they can help you more quickly and easily.
4. Use EXPAND to check a chemical name before searching. Remember to specify the /CN index.
5. Use the EXPAND E-numbers with the SEARCH command to avoid typographical errors.
6. Use the DISPLAY COST command at any time to estimate the cost of your online session so you don’t create a larger bill than you intended.
7. If you are having problems, get help when you need it. Feel free to call the STN Help Desk or another expert you know.
8. Use LOGOFF HOLD to save your session and L-numbers for 20 minutes without being charged. This is useful if you need to get more information, get help, or ask questions.
9. Consider using CAS Registry Services if you can’t easily get an answer or can’t confidently verify your answer. It may cost you less than searching online yourself.

© 1993 Education Committee, Division of Chemical Information, American Chemical Society