The Untangle products (NG Firewall and IC Control) have the ability to enforce the Safe Search features offered by major Search Engines. This option will prevent users from disabling the Safe Search on their machine, but will not guarantee that no inappropriate content will make it through the Safe Search results.
Please note that to enforce Safe Search on encrypted Search Engines (those that use HTTPS), you will need to follow the steps in this article: How To Get The Safe Search Option Working
What is Safe Search?
Safe Search is a collection of content that the Search Engine provider has classified as appropriate or inappropriate.
From: How SafeSearch works
“When SafeSearch is on, sexually explicit video and images will be filtered from Google Search result pages, along with results that might link to explicit content.
When SafeSearch is off, we'll provide the most relevant results for your search and may include explicit content when you search for it.”
“No filter is 100% accurate, but SafeSearch should help you avoid most adult images and sites.”
How do I report content that should be blocked?
Google has a page where you can report content that was not filtered out by Safe Search, so that they can review it and add it to their adult content list as needed.