The long-delayed United Kingdom anti-porn law, which will (at least in theory) block all online adult sites unless users can provide documents proving that they are over 18 years old, takes effect on July 15. And with less than a month to go, a new study of the law warns that it could be a “privacy time bomb” just waiting to explode on unsuspecting users.

The law creates a new system in which anyone who tries to access a porn site will be automatically redirected to a non-porn landing page where they will be required to upload official documents verifying their age.

According to a recent poll, as reported by AVN.com, most U.K. citizens will be surprised by their inability to access the porn sites, with 76 percent saying that they were unaware that the porn block was coming.

But the report by the watchdog Open Rights Group (ORG) says that they may be in for an even bigger surprise, because the protections in place to guard the privacy of porn site visitors is “vague, imprecise and largely a ‘tick box’ exercise.”

The privacy protections under the law are “voluntary” and don’t even contain specific rules or procedures for shielding sensitive user data from exposure, according to a summary of the ORG report by Forbes.com. Sites are required only to “consider” how to protect user data, and take some sort of measures to do so.

Not only that, but the law contains no penalties for sites and service providers that take no measures at all to protect the privacy of those who upload personal data.

As a result, the law’s privacy standards are “pointless, misleading and potentially dangerous as advice to consumers seeking safe products,” according to ORG executive director Jim Killock.

The law may even pose a threat to U.K. national security, as AVN.com reported, because any government official who tries to access a porn site will be left open not only to public embarrassment, but to possible blackmail by foreign governments whose hackers obtain their personal data.