About the Masthead
About RadiationBlocker
Lucia Castillo
Founder & Lead Editor
Nearly ten years tracking shielding attenuation standards, FCC regulatory filings, and independent lab reports across the consumer and commercial EMF-protection market.
The question that kept coming up in my work was deceptively simple: how do you evaluate a product whose primary claim is invisible? You can't see RF attenuation. You can't feel a Faraday cage doing its job. What you can do — what I set out to do systematically — is learn to read the evidence that surrounds a product: the published dB-attenuation figures, the third-party lab certifications, the patterns that emerge when you aggregate hundreds of owner reports across verified purchase reviews, Reddit threads, and specialist forums. That discipline is what radiationblocker.com is built on.
What I bring to this site is an analyst's habit of going one layer deeper than the marketing copy. When a brand claims 99% RF shielding, I look at which frequencies were tested, which testing standard was applied (ASTM, IEEE, or something proprietary), and whether independent reviewers corroborate the spec under real-world conditions. I've spent years tracking how the EMF-shielding category has matured — from novelty phone stickers with no measurable effect to genuinely engineered products from brands like DefenderShield, Mission Darkness, and Lambs that publish meaningful attenuation data. Knowing the difference between those two worlds is the core value I offer.
The way this site works is straightforward: I read everything so you don't have to. That means product listings, manufacturer white papers, FCC equipment authorizations, independent YouTubers who've run their own RF meters next to competing cases, and the long-tail of owner commentary that only becomes signal once you've read enough of it to filter the noise. When owners consistently report that a laptop shield runs hot underneath or that a Faraday bag fails to block signal at the seam, that pattern shows up in my recommendations regardless of how polished the brand's marketing is. Cost-per-use math also matters — a $180 shielding hoodie worn daily amortizes very differently than a $180 single-use purchase, and I make that arithmetic explicit.
What we refuse to do is equally important to name plainly. This site makes no medical claims, offers no diagnosis, and draws no conclusions about what any level of EMF exposure does or does not do to the human body. That is not our lane, and crossing into it would compromise both our editorial integrity and our readers' trust. We present manufacturer shielding claims neutrally — reporting what a brand says its product achieves and what independent data either supports or fails to support — and we stop there. We also refuse to recommend products whose only evidence is a proprietary in-house test, or to treat a higher price tag as a proxy for verified performance. Premium coverage here means rigorous coverage, not deference.
The readers I write for range widely, and I think that range is a feature. Some arrive because they just heard about 5G and want a $20 phone pouch that does something measurable. Others are pregnant and researching DefenderShield's maternity line with the same seriousness they'd bring to any prenatal decision. Some are IT security professionals evaluating Faraday bags for device transport. Some are building contractors specifying YShield paint for a sensitive facility. All of them deserve the same quality of analysis: clear, sourced, free of hype in either direction, and honest about what the published evidence actually shows.