The complete guide to Mineral Insulated Copper Clad (MICC) cable — Pyrotenax brand, magnesium oxide insulation, extreme fire and temperature resistance, specialist termination tools and moisture seals, applications, and honest cost vs benefit analysis.
Free for 7 days · No charge until day 8 · Cancel anytime · Used by 1,000+ UK electricians
Written and reviewed by Andrew Moore, founder of Elec-Mate, against BS 7671:2018+A4:2026, IET Guidance Note 3 and the IET On-Site Guide.
1,000+
UK electricians
“Replaced three separate apps with Elec-Mate. Certs, quotes, and scheduling all in one place.”
Daniel Palmer — DP Electrical
Mineral Insulated Copper Clad (MICC) cable — universally known in the UK electrical industry by the brand name Pyrotenax — is the highest-performance fire-resistant cable available. It is used wherever conventional polymer-insulated cables would fail under extreme fire or temperature conditions.
MICC cable consists of copper conductors embedded in highly compressed magnesium oxide (MgO) mineral insulation, all enclosed within a seamless drawn copper tube (the sheath). This construction is manufactured by feeding copper conductors through a copper tube packed with magnesium oxide powder, then drawing the assembly down through dies to compact the insulation and reduce the diameter to the finished cable size.
Every key change in the 2026 amendment on one page. AFDDs, TN-C-S protection, new schedule columns, model forms. Pinned on your van dash.
Understanding the construction of MICC cable helps explain both its exceptional properties and the specialist handling it requires during installation.
MICC cable's fire performance far exceeds that of any polymer-insulated fire-resistant cable. This performance advantage is the reason MICC is specified for the most demanding fire-critical circuits.
For circuits specified to maintain function for 60 or 90 minutes under fire conditions (as required by some fire engineering designs and fire authority specifications), MICC is often the only cable type that can demonstrate compliance with certainty.
Correct termination is the most skill-intensive aspect of MICC cable installation. Incorrect termination is the most common cause of MICC installation failures, typically manifesting as low insulation resistance due to moisture ingress.
After termination, test insulation resistance between conductors and between each conductor and the sheath earth using a 500V DC insulation resistance tester. Readings below 1MΩ indicate moisture in the insulation. Baking out the cable (heating the termination with a heat gun while the insulation resistance is monitored) can restore readings in mildly damp cables.
MICC cable is specified where no other cable type provides adequate performance. Its high cost means it is reserved for applications where its unique properties genuinely justify the investment.
16 certificate types, 70+ calculators, RAMS, quoting, invoicing, AI agents, and 46+ training courses — from £6.99/mo.
Start free trial
Both MICC and FP200 Gold are accepted by BS 5839-1 for fire alarm circuits and by BS 5266-1 for emergency lighting. The choice depends on the specific fire engineering requirements and budget.
See the FP200 Gold cable guide for full details on fire-resistant cable for standard fire alarm and emergency lighting installations.
MICC cable is significantly more expensive than any alternative fire-resistant cable, both in material cost and installation time. Understanding where this cost is and is not justified is important for project pricing and specification.
MICC cable installations must be certified with the appropriate Electrical Installation Certificate, with test results including insulation resistance values for each conductor to sheath and between conductors. Low insulation resistance on MICC is almost always a termination moisture issue.
Use the Elec-Mate certificate app to issue Electrical Installation Certificates for MICC installations. Record insulation resistance test results, cable type, and installation details — produce the PDF on site before you leave.
Elec-Mate's EIC and EICR apps let you certify fire-critical MICC cable installations on site.
Try it free for 7 daysVerified reviews from the UK App Store.
Elec-Mate is my go to app for business and electrical work. It's feature rich without feeling cluttered. A true all in one app for quotes, certs, calculations, RAMS, EICRs, and more. I use it every day without fail, and it makes my workflow much smoother since I'm not jumping between apps anymore. The price-to-feature ratio is excellent. Any issues I've had, the developer responds within the hour and usually fixes them the same day. 100% recommend.
I've used the app and the web based version for a while now and it's well worth the investment. If you're an apprentice or experienced Spark give it a go, you won't be disappointed.
I've been using Elec-Mate for a while now, and honestly, it's one of the best apps I've ever downloaded. Every aspect of it feels thoughtfully designed, from the clean and intuitive interface to the powerful features that make everything so easy to manage. It's clear that a lot of care and attention went into building this app, and it shows in every detail.
Real feedback from real sparks
“Replaced three separate apps with Elec-Mate. Certs, quotes, and scheduling all in one place.”
Daniel Palmer
Sole Trader · DP Electrical
“I've won two contracts this month because I could turn quotes around same-day with the AI cost engineer.”
Nathan Perry
Electrician · NP Electrical Services
“The study centre got me through my AM2. Mock exams and flashcards are brilliant.”
Jake Pizey
3rd Year Apprentice · Apprentice
Join 1,000+ UK electricians using Elec-Mate to certify fire-critical cable installations on site. Record insulation resistance test results and cable details — instant PDF export. 7-day free trial.
“Replaced three separate apps with Elec-Mate. Certs, quotes, and scheduling all in one place.”
Daniel Palmer, DP Electrical
From £6.99/mo after trial — less than a coffee a week
We use cookies to improve the app and measure what works. Cookie Policy