Coastal solar street lights in Morocco: IP66 and corrosion

Coastal solar street lights on the Casablanca Corniche, in Mohammedia or in El Jadida operate in a C5 marine atmosphere in the sense of ISO 9223: zinc loses 4.2 to 8.4 µm per year there, against 0.7 to 2.1 µm/yr in town more than a kilometre from the shore. The specification that lasts: an IP66 die-cast aluminium housing with a marine-grade coating and a salt spray test report, a hot-dip galvanised pole to ISO 1461 (≥ 85 µm on steel ≥ 6 mm) in a duplex system, and A4 stainless fasteners. Beyond one kilometre from the sea, the standard IP65 version and galvanising alone are usually sufficient.

Why does Casablanca's air attack a street light faster than Marrakech's?

Two factors govern atmospheric corrosion under ISO 9223: the time surfaces stay wet and the deposition of chlorides. Casablanca has both: relative humidity of about 82 % all year (80 % in Rabat), a sea breeze loaded with spray, and on the Corniche or in the port zone surfaces that never really dry. A housing installed in Marrakech dries every morning and sees no salt; the same housing installed at Aïn Diab stays damp and salty, and the smallest scratch in the coating becomes a starting point. It is not the panel, the battery or the LEDs that age, but the pole, the fasteners, the housing and the gaskets.

Which ISO 9223 corrosivity class applies to the Corniche, Mohammedia, El Jadida or Bouskoura?

ISO 9223:2012 classifies atmospheres from C1 to CX by the corrosion rate of zinc, which translates directly into the life of a galvanised coating:

There is no Moroccan ISO 9223 map and no published exposure study for Casablanca. LALOGO therefore applies an engineering classification by distance to the sea, which we label as such in our offers:

Three of the six communes covered by the lighting master plan (SDAL) of SRM Casablanca-Settat, namely Casablanca, Mohammedia and El Jadida, are on the coast (LesEco, 21 May 2026); Bouskoura and Bni Yakhlef are inland. A single road contract in the region can therefore mix C5 and C3 sites.

How many years does an 85 µm hot-dip galvanised coating last by the sea?

ISO 1461 requires a minimum mean zinc thickness of 85 µm on steel of 6 mm and above, and 70 µm between 3 and 6 mm; the minima fall further for thinner sheet, which directly concerns conical poles (wall 1.5 to 2.75 mm on our LS-P6 drawing). The arithmetic is blunt: at 8.4 µm/yr, the top of the C5 range, 85 µm of zinc are consumed in ≈ 10 years; at 2.1–4.2 µm/yr (C4), in 20 to 40 years; in C3, in 40 years and more. In C5, galvanising alone therefore does not cover the expected life of a pole. The answer is the duplex system: hot-dip galvanising to NM ISO 1461, then a polyester powder coat sized to ISO 12944-5 for C5 with a durability class of at least 15 years. That is our recommendation, anchored in the texts the draft NM 06.8.001 cites (§ 5.7: poles hot-dip galvanised to NM ISO 1461, corrosivity to NM ISO 12944). The pole is of Moroccan origin (25 % safeguard duty on imported poles, HS 7308.90.10); the customs classification of the luminaire is confirmed by our freight forwarder. The LS-P6 drawings (5.7 to 7.8 m, anchor cage included) are supplied to the Moroccan fabricator of your choice, with the duplex note for C5 lots.

IP65 or IP66: what is the difference for a coastal solar street light?

The first digit of the IP rating (NM EN 60529) describes protection against solids, the second against liquids. IP65 and IP66 are both dust-tight; the difference is water: IP65 withstands water jets, IP66 withstands powerful jets, that is, packets of spray and driving rain pushed by the sea wind. On the Corniche, rain does not arrive vertically: it is thrown at the gaskets, the cable glands and the battery compartment. The draft NM 06.8.001 leaves the IP and IK ratings "specified by the client" (§ 7); our recommendation for tender specifications is IP66 and IK08 minimum on the coast, IP65 and IK08 inland, with impact resistance (NM EN 62262) refined according to the vandalism exposure.

Our all-in-one solar street lights are IP65 as standard, with an IP66 coastal version with marine-grade coating and salt spray test report on request; the LS-F100 and LS-F200 floodlights are IP66 from the outset.

How many salt spray hours (ISO 9227) should a specification demand?

The ISO 9227 neutral salt spray test is the only quick way to compare two coatings. Commercial practice for luminaires destined for the coast is to require at least 1 000 h without blistering or creep from a scribe, against 500 h commonly requested inland. This is not a Moroccan regulatory requirement, it is market practice, and you are free to write your own value into the specification. Ask for the test report of the housing, the fasteners and the pole separately: a duplex pole certified at 1 000 h fitted with ordinary zinc-plated fasteners rusts through the fasteners first.

Which design details make the difference: fasteners, galvanic couples, gaskets, drainage?

• A4 (316) stainless fasteners on everything exposed: pole clamps, panel bracket, battery cover. A2 stainless stains and pits in C5.
• Galvanic couples: a die-cast aluminium housing clamped onto a galvanised steel bracket forms a cell in the presence of salt water; an insulating washer and assembly paste are enough, provided they are planned for.
• Gaskets and cable glands: continuous silicone or EPDM gasket, metal cable glands, no cable entry on the face exposed to the wind.
• Drainage and breathing: an IP66 housing must shed condensation; a pressure-equalising membrane avoids sucking in humid air at every day and night cycle.
• Photovoltaic panel: in C5 we prefer the separate panel on a galvanised LS-B bracket, tiltable from 15 to 45°, which is replaced without touching the luminaire.
• Battery: the draft NM 06.8.001 allows the battery box at the pole base or in the foundation (§ 5.4); on the coast it is easier to inspect than a battery housed under the panel.
• Wind: on very exposed sites such as Essaouira or Tarfaya, the LS-K wind and solar hybrid street light earns its place, with a pole sized accordingly.

Which LALOGO version should you specify by distance to the sea?

On a seafront development in Dar Bouazza this means, for example, LS-A80 units (8 000 lm, 6 m poles, 20 to 25 m spacing) in the IP66 coastal version on duplex poles; on a main road in a Mohammedia industrial zone, LS-A120 units or LS-S100 split kits (7 to 8 m poles) in C4; in Bouskoura, the standard IP65 version. In all three cases the reports are requested before the order, not after the first winter.

Key takeaways

• The Casablanca-Settat coast is C4 to C5 under ISO 9223: zinc loss of 2.1 to 8.4 µm/yr, against 0.7 to 2.1 µm/yr in Bouskoura or Bni Yakhlef (LALOGO engineering classification, no official map exists).
• An 85 µm galvanised coating lasts ≈ 10 years in C5 and 20 to 40 years in C4: on the seafront, require a duplex pole (ISO 1461 and ISO 12944-5, durability ≥ 15 years).
• IP66 on the coast, IP65 inland; NM 06.8.001 leaves IP and IK to the client, so write them into the specification.
• ISO 9227 salt spray: 1 000 h in coastal zones is market practice, not a Moroccan rule; ask for the reports on the housing, the pole and the fasteners.
• A4 stainless fasteners, insulated aluminium-to-steel joints, metal cable glands, battery box at the pole base: the details that show after five winters.
• A pole of Moroccan origin in every case (25 % safeguard, HS 7308.90.10); LS-P6 drawings supplied with the duplex note for C5 lots.

Sources

• ISO 9223:2012, corrosivity of atmospheres, classification: iso.org/standard/53499.html
• American Galvanizers Association, corrosion rates of hot-dip galvanised zinc by ISO class C1 to CX: galvanizeit.org
• IMANOR, NM 06.8.001 catalogue entry: imanor.gov.ma/Norme/nm-06-8-001/ and draft EP 52/2024: PDF
• IMANOR, guide on applying standards in public procurement, February 2026: PDF
• LesEco, 21 May 2026, on the SDAL of the six Casablanca-Settat communes: leseco.ma
• Casablanca climate, relative humidity (NOAA / DWD): en.wikipedia.org/wiki/Casablanca