- Client
- NITROX 21 SL
- Website
- proteccionrespiratoria.es (formerly nitrox21.es)
- Location
- Alcalá de Guadaíra, Seville
- Industry
- Respiratory protection and underwater work
- Services
- Domain migration · Specialty-based structure · Technical SEO
- Stack
- WordPress + custom theme
- Delivered
- 2026
From a legacy domain to a technical platform with a name of its own
NITROX 21 SL carries on more than thirty years of work in respiratory safety and underwater operations from Alcalá de Guadaíra, Seville: maintenance and inspection of self-contained breathing apparatus (SCBA, known in Spanish as ERA), an official technical service for diving equipment and professional underwater operations for industries where equipment failure is not an option — fire services, the chemical industry, water utilities and wastewater treatment plants, mining, ports, defense.
The challenge wasn’t only aesthetic. The brand operated under the domain nitrox21.es, a name that says nothing about what the company does or how its actual customers look for it. The brief was to move its online presence to proteccionrespiratoria.es (Spanish for “respiratory protection”), a domain aligned with how the industry searches, without losing authority or history, and to build on top of it a structure that would organize five service areas and ten client industries that previously had no clear place on the site.
A note on transparency. nitrox21.es has no copies in the public Wayback Machine archive, so we can’t show exactly what that domain looked like. There is a snapshot of proteccionrespiratoria.es from January 10, 2025, which we use here as the closest reference to the state of things before the project: web.archive.org · Jan 10, 2025.
Same business, a domain that finally says what it does
One structural decision drove everything: organize by technical specialty, not by product
NITROX21 doesn’t sell equipment: it maintains, inspects, rents out and trains. That distinction — which is also its selling point against generic distributors — became the backbone of the new information architecture.
Specialty-based structure
Five service areas (respiratory protection, diving equipment maintenance, underwater work, rental, training) with a dedicated content type for individual services, each with its own semantic URL and page.
Visible technical credibility
ISO 9001, 14001 and 45001 certifications, official technical service for Aqualung, Apeks, 3M Scott Safety and Cressi, and the applicable regulations (RD 773/1997, RD 809/2021, EN 137, EN 12021, EN 250) shown right on the home page, not buried in an “about” page.
A visual identity that fits the industry
Barlow Condensed for headings and JetBrains Mono for the technical identity, on a dark palette with an amber accent. No generic “service company” template: the look is closer to a technical data sheet than to a sales catalog.
The domain migration, done without losing authority
We confirmed live that nitrox21.es redirects with a permanent 301 to proteccionrespiratoria.es, over both HTTP and HTTPS. That’s the correct way to move a domain without losing the link history or forcing Google to index two different brands for the same business.
SEO and technical structure: what holds the migration up
Changing domains also carries risk: if the technical SEO isn’t done properly, visibility drops right when the switch happens. This is what we verified live on the current site.
What it means for the business
- Nobody gets left at the door by the domain change. Anyone arriving through nitrox21.es or an old link ends up at the new address. The permanent redirect is also the signal that tells Google to move the old domain’s reputation there.
- Google knows where the company is and how long it has been around. The home page declares the address, the location on the map and the year the company was founded (1996), information Google can use in local searches.
- Every customer reaches what matters to them. Services and industries have their own pages that link to each other: a fire station or a wastewater treatment plant finds its case without going through the whole catalog.
See the technical detail (7 points)
- Permanent 301 redirect from nitrox21.es to proteccionrespiratoria.es, consolidating the previous domain’s authority.
- Custom WordPress theme (“nitrox21”), with no heavy page builder.
- Dedicated content type for services with its own XML sitemap (
wp-sitemap-posts-servicio-1.xml). - Schema.org LocalBusiness with address, geolocation and founding date (1996) on the home page.
- Complete meta tags:
title,description, Open Graph and Twitter Card. - HTTP/2 + HSTS enabled.
- Industry structure kept separate from the services structure, so “what we do” can be matched with “who it’s for” without duplicating content.
Search visibility built for the industry, not just the city
Alcalá de Guadaíra and Seville appear naturally in the content and in the schema, but the real SEO work here is semantic: Spanish search terms such as “mantenimiento equipos ERA Sevilla”, “servicio técnico oficial Aqualung Andalucía” or “buceo profesional industrial Sevilla” are proposed search intents based on the client’s actual services — this is our own qualitative estimate, not Search Console data, and it would need to be validated with real data once the site builds up traffic on the new domain.
The site isn’t the end of the project. It’s the starting line
A domain migration doesn’t end on launch day: authority comes back over weeks, not hours. The work that follows is monitoring how the new domain gets indexed in Search Console, confirming that Google correctly attributes the link history to proteccionrespiratoria.es, and measuring the real impact on traffic and rankings before publishing any figures.
We don’t include traffic, ranking or performance data (Lighthouse, Core Web Vitals) here because we don’t yet have a verified measurement after the migration. We’d rather show an honest case study with no marketing figures than one with numbers we can’t back up.