Stainless steel is the material of choice for drains, gratings and fabricated items, but “stainless” is not one material. The two grades you will meet most often are AISI 304 and AISI 316. On delivery they look identical. A year later, in the wrong location, they can look very different.
What is the difference?
Both grades are austenitic stainless steels with chromium and nickel. SS 316 adds molybdenum, which greatly improves resistance to chlorides: the salts found in seawater, coastal air, swimming-pool water and many cleaning products.
Where SS 304 works well
- Internal bathrooms and kitchens away from the coast.
- Dry indoor areas with normal cleaning routines.
- Cost-sensitive projects where exposure is low.
Where SS 316 is the better choice
- Buildings near the coastline, which in the UAE means a large share of projects.
- Swimming pools, pool decks, spas and splash zones.
- Commercial kitchens and food areas with aggressive cleaning chemicals.
- External podiums, terraces and roofs exposed to humidity and salt-laden air.
Finish matters too
A smooth, well-polished or brushed surface is harder for contaminants to cling to and is easier to clean. Rough or poorly finished welds are often where tea staining begins. Ask for properly pickled and passivated welds on fabricated items.
Maintenance still counts
Even SS 316 benefits from regular rinsing with fresh water in coastal and pool areas. Avoid cleaning with steel wool or chlorine-based cleaners, which can leave deposits that start surface corrosion.
Quick guide by product
| Product | Recommended grade |
|---|---|
| Indoor floor drains (dry, inland) | SS 304 or SS 316 |
| Coastal villa drains, pool channels | SS 316 |
| Bollards, roof hatches, outdoor drip trays | SS 316 |
| Commercial kitchen drains | SS 316 |
| Indoor work tables and trolleys | SS 304 |
How to tell them apart
SS 304 and SS 316 look identical. Ask for mill certificates and check that the grade is stated on the submittal and the delivery note.
Tea staining
Tea staining is light brown surface rust that appears on stainless steel near the sea or pools. It is mostly cosmetic. It can be removed with a stainless steel cleaner and prevented by choosing SS 316, a smooth finish and regular fresh-water rinsing.
Frequently asked questions
Is SS 316 always worth the extra cost?
Not indoors in dry, inland areas, where SS 304 performs well. For coastal, pool, kitchen and external areas, SS 316 is worth it.
Can SS 304 be used outdoors?
It can, away from the coast and with regular cleaning, but SS 316 is the safer choice outdoors in the UAE.
Do you supply both grades?
Yes. Drains, gratings and fabricated items are available in SS 304 and SS 316.
Our recommendation
If you are unsure about the exposure, specify SS 316 for drainage. The cost difference is small compared with replacing stained or pitted products later. We supply fabricated items in both grades. Explore our stainless steel fabrication capabilities.
Related products: stainless steel manhole covers · stainless steel floor drains · stainless steel fabrication
Related products: SS Gullies & Floor Traps · Stainless Steel Bollards · SS Drip Trays · SS Work Tables & Trolleys