Safety Footwear for Gas Carriers: The EN ISO 20345 Standard

Working on board a gas carrier (LNG/LPG) exposes seafarers to a unique combination of hazards. From the extreme cold of cryogenic spills to the constant risk of explosive atmospheres and slippery steel decks in the engine room, proper Personal Protective Equipment (PPE) is non-negotiable. At the foundation of this protection is safety footwear. This engineering overview breaks down the critical requirements of the EN ISO 20345 standard specifically tailored for maritime professionals on gas carriers.

Decoding the EN ISO 20345 Classifications

The EN ISO 20345 standard defines the basic and additional requirements for safety footwear used for general purposes. For the demanding environment of a gas carrier, a basic safety shoe is insufficient. You must look for specific classification codes:

• S3 or S3S: This is the baseline recommendation for maritime work. “S” stands for Safety (indicating a protective toe cap tested to 200 Joules). The “3” indicates that the shoe possesses antistatic properties, energy absorption in the heel, resistance to fuel oil, a water-resistant upper (crucial for deck work), and a penetration-resistant midsole to protect against stepping on sharp objects like nails or metal shards. (S3S indicates a non-metallic penetration-resistant insert).
• SRC (Slip Resistance): Slips, trips, and falls remain the highest cause of injury at sea. SRC means the footwear has been tested for slip resistance on both ceramic tile wetted with a dilute soap solution and smooth steel wetted with glycerol. A deep, self-cleaning “ladder grip” tread pattern is essential for safely navigating steep engine room stairways.

More information on Combating Corrosion and Transitioning from VLSFO to LSMGO

Critical Additional Requirements: ESD and HRO

For engine room staff and those working on the cargo deck, two additional markings are highly recommended, if not mandatory, depending on the company’s SMS:

ESD (Electrostatic Discharge)

While S3 shoes are “antistatic” (meaning they dissipate electrostatic charges to a degree), ESD certification is much stricter. Gas carriers operate in hazardous zones (Zone 0, 1, 2) where a tiny static spark from a human body could ignite a gas-air mixture. ESD shoes ensure a very low, continuous electrical resistance (between 100 kΩ and 35 MΩ), safely grounding the wearer at all times and preventing spark generation.

HRO (Heat Resistant Outsole)

In the engine room, marine engineers frequently walk on hot steel gratings near boilers, purifiers, and steam lines. Footwear marked with HRO has an outsole that can withstand contact with a surface at 300°C for 60 seconds without melting or cracking. This prevents severe burns and extends the lifespan of the boot.

Material and Ergonomics

The upper material must be rugged yet breathable, often full-grain leather treated for water and chemical resistance. Given the 12-hour shifts typical of maritime contracts, ergonomics cannot be ignored. Look for boots with lightweight composite toe caps (which don’t transmit cold like steel) and advanced shock-absorbing insoles to reduce fatigue and knee strain from constant walking on hard steel decks.