External Lights IP Rating

Choosing an outdoor light that is not up to the job will result in disappointment.  The light fitting is generally exposed to the weather and frequently in NZ to salt spray near the coast.
The lights, especially halogen lights,can become quite hot and this accelerates corrosion .

The best materials in decreasing order of cost are 316 Grade Stainless Steel, copper and brass.  Powder coated aluminium is  fine if the powder coating and aluminium are of good quality.  Grade 304 Stainless is a lower cost option but it will show rust stains after a while.  These can be removed by using a scouring pad and then protect the  stainless steel with clear lacquer or car polish.

An international standard to judge the suitability of a light for its location is the IP rating.
This stands for Ingress Protection and the rating has two numbers.
The first number is the standard of protection against the entry of dry particles, the second number is the protection against the entry of moisture. 

Foe example The Hunza Pool Light is rated IP 68

 

First Number                                                Second Number

 

1	Protection against entry of objects larger than 50 mm - hands	1	Protection from falling vertically falling drops of water
2	Protection against entry of objects larger than 12 mm - fingers	2	Protection from direct sprays up to 15 degrees from vertical
3	Protection against entry of objects larger than 2.5 mm - tools	3	Protection from direct sprays up to 60 degrees from vertical
4	Protection against entry of objects larger than 1.0 mm - wires	4	Protection from entry of water splashes or spray from any direction
5	Protection against entry of dust in sufficient quantity to prevent satisfactory operation	5	Protection from a low pressure jet of water from any direction
6	Complete protection against entry of dust	6	Protection against a strong jet of water from any direction
		7	Protection against immersion up to 1 metre
		8	Protection against immersion over 1 metre