The final consideration for using an RF module is regulatory compliance. Some compliance testing is likely to be required, even on modules listed as pre-certified. For example, the FCC does not allow modular certifications on receivers or unintentional radiators. This will require the end product be tested for compliance with the regulations governing unintentional radiators. Fortunately, this testing is about half the cost of the transmitter testing and does not involve any filings or fees with the FCC. Likewise, the European regulations require the end product be tested for immunity to other transmissions as well as some safety and ESD testing. Again, the expense for these tests is not as great as with the transmitter. It is important for the designer to be aware of the required testing at the start of the design process, even if the module is sold as pre-certified.