What is the Standard Horizon HX400IS?
The Standard Horizon HX400IS is the intrinsically safe version of the HX400 — a 5-watt, commercial-grade handheld VHF radio certified to ANSI/UL 913 (5th Edition) for Class I, II, and III, Division 1 hazardous locations. It's built for crews working around flammable gases, combustible dust, or ignitable fibers.
It carries all USA, International, and Canadian marine channels, can be programmed with up to 40 Land Mobile Radio (LMR) channels from 134 to 174 MHz, and keeps the HX400's built-in voice scrambler, noise-canceling microphone, and IPX8 submersible rating.
At a glance
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Product Page by Kristin Wood, a two-way radio consultant @ Tech Wholesale | Last Updated: October 2026
Technical Specifications
What's Included
- Standard Horizon HX400IS radio
- CAT460 flexible antenna
- 2550 mAh intrinsically safe lithium-ion battery
- CD-50 charging cradle
- PA-45B 110V AC wall charger for the cradle
- CLIP-22 belt clip
- Hand strap
- Owner's manual
Note: Unlike the standard HX400, the HX400IS does not ship with a 12V DC charging cable.
HX400IS Key Features
Intrinsic safety
UL 913 Division 1 certified
Certified for Class I, II, and III, Division 1 hazardous locations — areas where flammable gases, combustible dust, or ignitable fibers can be present during normal operations.
Gas, dust, and fiber coverage
Class I Groups C and D (ethylene, propane), Class II Groups E, F, and G (metal, coal, and grain dust), and Class III fibers and flyings, with a T3 temperature code.
Matched IS accessories
The rating holds with the IS battery and Standard Horizon's approved IS speaker mics. Swapping in other parts may void it.
Privacy & clear audio
Built-in voice scrambler
Turn on scrambling channel by channel with one of four codes. Anyone listening without a matching Standard Horizon scrambler hears garbled audio.
Noise-canceling microphone
Cuts machinery, pump, and wind noise from your transmissions so the other end hears you clearly.
700 mW speaker
Loud enough to hear over engines and equipment without a headset.
Marine + land mobile
40 programmable LMR channels
A dealer can add up to 40 land mobile channels between 134 and 174 MHz, set wide or narrow, with CTCSS or DCS codes. Talk on your licensed business channels and marine channels from one radio.
All USA, International & Canadian marine channels
Switch marine bands from the keypad. A U, C, or I on the display shows which band you're on.
Programmable channel names
Label channels with up to 12 characters — DECK, PUMP RM, CREW 2 — so nobody has to memorize channel numbers.
Durability & power
IPX8 submersible to 1.5 meters
Rated for about 5 feet of water for 30 minutes, with the battery attached and the accessory jack capped.
Selectable 5W / 1W output
One press of the H/L key switches between full 5 watts for distance and 1 watt for short-range calls and longer battery life.
17-hour removable battery
The 2550 mAh IS battery is rated for about 17 hours and charges in about 3 hours. Swap batteries only outside the hazardous area.
Weather, scanning & controls
Instant channel 16
The 16/9 key jumps straight to the distress and hailing channel from anywhere. Press and hold for channel 9.
NOAA weather + weather alert
Hold the CLR/WX key to jump to NOAA weather, and get a loud beep when NOAA broadcasts a severe weather alert.
Memory scan, priority scan & Tri-Watch
Scan your saved channels, add a priority channel the radio keeps checking, or watch channels 16 and 9 alongside your working channel.
10 presets + keypad lock
The PRESET key recalls up to 10 favorite channels. Hold the H/L key to lock the keypad so a bump doesn't change your channel.
Compatible Accessories for the Standard Horizon HX400IS
Keep it intrinsically safe: only the IS battery and the IS-approved speaker microphones below keep the UL 913 rating. Other HX400 accessories — including the FBA-42 AA tray, VOX headsets, and earpieces — are not part of the IS approval.
IS-Approved Speaker Microphones
CMP460 — Noise-Canceling Waterproof Speaker Microphone
An IS-approved speaker mic with its own noise canceling, so your voice stays clear even with the radio on your belt.
SSM-14A — Submersible Speaker Microphone
A submersible, IS-approved speaker mic for wet decks and washdown areas.
MH-66D4B — Submersible Speaker Microphone
Listed in the HX400IS owner's manual as an IS-approved speaker mic option.
IS Battery
SBR-45LIIS — 2550 mAh Intrinsically Safe Lithium-Ion Battery
The current IS replacement battery for the HX400IS. Keep a charged spare — and swap it outside the hazardous area.
Chargers
CD-50 — Charging Cradle
The same drop-in cradle that ships with the HX400IS. Not waterproof and not for use in hazardous locations.
PA-45B — AC Wall Charger
Replacement 110V wall charger for the CD-50 cradle.
SAD-1460 — 6-Unit Multi Charger
Charges six radios at once — built for fleets that check radios in and out every shift.
Who Is This Radio For?
The HX400IS is for crews who need a marine VHF radio in places where a spark could ignite the air around them.
1. Tankers, Fuel Barges, and Fuel Docks
Crews transferring fuel, LPG, or chemicals work around flammable vapors. The HX400IS is certified for Class I, Division 1, Groups C and D, which covers propane and ethylene atmospheres.
2. Offshore Platforms and Marine Terminals
Platform and terminal crews need marine channels to reach supply vessels and LMR channels to reach the control room. One IS-rated radio covers both.
3. Grain, Coal, and Bulk Cargo Operations
Loading grain or coal throws fine dust into the air. The Class II, Groups E, F, and G rating covers metal, coal, and grain dust in Division 1 areas.
4. Ports, Refineries, and Chemical Plants on the Water
Safety teams that move between hazardous and non-hazardous areas can carry one radio all day. The scrambler and noise-canceling mic keep calls private and clear.
Important: Marine VHF channels can only be used on the water. Using the HX400IS on land is only legal on LMR channels your organization holds an FCC license for. If you need intrinsically safe radios for land-only sites, contact our team and we'll point you to the right business radio.
How Does the HX400IS Compare to Similar Radios?
| Standard Horizon HX400IS | Standard Horizon HX400 | Standard Horizon HX380 | |
|---|---|---|---|
| Intrinsically Safe | Yes (UL 913, Div. 1) | No | No |
| Max Power | 5W | 5W | 5W |
| Land Mobile (LMR) Channels | Yes, up to 40 | Yes, up to 40 | Yes, up to 40 |
| Waterproof Rating | IPX8 (1.5 m) | IPX8 (1.5 m) | IPX7 (1 m) |
| Voice Scrambler | Yes | Yes | No |
| 12V DC Cable Included | No | Yes | Yes |
| AA Backup Option | No (not IS-approved) | Yes (FBA-42) | Yes (FBA-40) |
| Best For | Hazardous locations | Commercial crews who need privacy | Commercial crews on water and land |
HX400IS vs. HX400
They're the same radio on the outside — same scrambler, noise-canceling mic, LMR channels, and IPX8 rating. The HX400IS adds UL 913 intrinsic safety certification, with a matched IS battery and a short list of approved speaker mics. If your crew never enters a classified hazardous area, the standard HX400 gives you more accessory options and a 12V cable in the box.
HX400IS vs. HX380
The HX380 covers marine and LMR channels for less, but it's IPX7 and has no scrambler, noise-canceling mic, or IS rating. For crews working around fuel, gas, or combustible dust, the HX400IS is the only one of the three built for it.
Frequently Asked Questions
What does "intrinsically safe" mean?
An intrinsically safe radio is designed so it can't produce enough electrical or heat energy to ignite flammable gases, dust, or fibers in the air.
The HX400IS meets ANSI/UL 913 (5th Edition) for Class I, II, and III, Division 1 hazardous locations, with a T3 temperature code.
Which hazardous locations is the HX400IS rated for?
Class I, Division 1, Groups C and D: flammable gases and vapors such as ethylene and propane.
Class II, Division 1, Groups E, F, and G: combustible metal, coal, and grain dust.
Class III: ignitable fibers and flyings.
It is not rated for Class I Groups A or B (acetylene and hydrogen). Always confirm your site's classification with your safety officer before choosing a radio.
What keeps the IS rating valid?
The rating only applies with the intrinsically safe battery and Standard Horizon's approved IS speaker mics (CMP460, SSM-14A, MH-66D4B). Substituting other parts may void it.
Also, never charge, swap batteries, or plug in a speaker mic inside a hazardous area. Do all of that in a non-hazardous location.
Can I use the AA battery tray or a headset with the HX400IS?
Not in hazardous locations. The FBA-42 AA tray, VOX headsets, and earpieces from the standard HX400 are not part of the HX400IS's IS approval.
For hands-free or remote audio, use an IS-approved speaker mic like the CMP460.
Do I need a license to use the HX400IS?
Marine channels: most vessels in U.S. waters that aren't required to carry a radio don't need a ship station license. Commercial vessels and international voyages may.
LMR channels: yes. Land mobile channels require an FCC license, and the radio can only be programmed with frequencies your organization is licensed for.
Who programs the LMR channels?
Standard Horizon says the 40 LMR channels are programmed by a dealer. You'll need your FCC license details — frequencies, wide or narrow, and any CTCSS or DCS codes.
Contact our team with your license info and we'll help you get set up.
How does the voice scrambler work?
It's a 4-code voice inversion scrambler you turn on per channel. Only other Standard Horizon radios with a scrambler set to the same code can understand you.
Voice inversion keeps casual listeners out, but it isn't encryption. Don't rely on it for highly sensitive information.
Does the HX400IS float or have a strobe light?
No. It's IPX8 submersible — about 5 feet of water for 30 minutes — but it isn't built to float and has no strobe light. Some listings online say otherwise.
Use the hand strap or belt clip when working over the side.
Why Buy the Standard Horizon HX400IS from Tech Wholesale?
- 3-year waterproof warranty — Standard Horizon's full coverage, handled through us.
- 30-day returns — Not the right fit? Send it back.
- Lifetime tech support — Real people answering your questions since 1997.