The Safety Word List: after hours emergency call triage that never makes the safety call

The three parts

The Safety Word List is a rule for any AI agent, answering service or night line that picks up your after-hours calls: it never decides whether a call is a safety emergency. It matches words. It has three parts, in this order:

1. The list. A short, written list of words and phrases that always mean "safety first": gas smell, rotten eggs, carbon monoxide alarm and the rest of the list below.
2. The fixed message. When a call uses one of those words, the caller hears or reads a message your company wrote and approved in advance, telling them to get out and call 911 or the utility. Nothing improvised.
3. The page. At the same moment, the agent pages your on-call tech or manager, so a real person knows right away.

Every other call goes to a person who decides what happens next. The rest of this page is the list, the message to copy and the paging setup.

Who this is for

HVAC, plumbing and home-service companies that take calls at night or on weekends, whether a person, an answering service or an AI agent answers them. If an agent is going to book jobs after hours, set this up first.

Why the agent should match words, not judge

You'd think a smarter agent should listen, weigh how serious it sounds and decide. That's the wrong job for it. The advice for a gas smell doesn't depend on how serious the caller thinks it is: the American Gas Association says to leave the building right away, avoid anything that could make a spark, and call 911 or your gas utility from a phone away from the area. The federal pipeline safety office gives the same advice for a suspected leak: leave on foot, don't use switches or phones nearby, call from a safe place.

Carbon monoxide is the same. The Consumer Product Safety Commission says that if you suspect CO poisoning, get outside to fresh air immediately and then call 911, and lists symptoms like headache, dizziness, weakness, nausea and confusion. Kidde's instructions for a sounding CO alarm say to call 911 or the fire department, get to fresh air and account for everyone.

So the correct response to these calls is already written. An agent that improvises can only make it worse. A word list makes it predictable, and it can be tested.

What you need first

• The name and number of whoever is on call each night, in a schedule the agent can read (a shared calendar is fine).
• A paging channel that wakes that person up: a phone call, a text, or your on-call app. A text alone is often too quiet at 2 AM.
• Your gas utility's emergency number for the area you serve. Local utility instructions take precedence over general advice.
• Someone with authority (the owner or service manager) to approve the message once, in writing.

Write the list (part 1)

Start with these, then add words your own callers use. Match whole phrases and common misspellings.

Group	Words and phrases to match
Gas	gas smell, smell gas, smells like gas, rotten eggs, sulfur smell, hissing at the meter, gas leak
Carbon monoxide	CO alarm, carbon monoxide, detector going off, alarm chirping and headache, everyone feels dizzy
Fire and electrical	smoke, burning smell, sparks, outlet melted, panel buzzing
Water and people	water near the panel, flooding near electrical, someone fainted, can't breathe

The AGA notes that utilities add an odorant that smells similar to rotten eggs, which is why "rotten eggs" and "sulfur" are on the list even when the caller never says "gas".

Two rules for the list:

• When in doubt, it's on the list. A false match costs you a page to your on-call tech. A miss costs far more.
• The agent can't remove words. Only a person changes the list, and the change is dated.

Write the fixed message (part 2)

This is the message the caller gets, by voice and by text, the moment a word matches. Copy it, put your company name and utility number in, and have the owner approve it.

This is [company]. If you smell gas or your carbon monoxide alarm is sounding, leave the building now and take everyone with you. Don't turn lights or appliances on or off. From outside or a neighbor's phone, call 911 or [gas utility] at [utility emergency number]. We've paged our on-call technician, who will call you back.

What the message never does: promise an arrival time, quote a price, tell the caller it's probably nothing, or ask them to go check the furnace. If the caller keeps talking, the agent repeats the first two sentences.

Set up the page (part 3)

At the same time as the message, the agent sends the on-call person a page with:

SAFETY MATCH: "[matched words]" at [time]
Caller: [name], [callback number], [address if given]
Message played: yes, [time]
Transcript: [link]

Route it to a phone call first and a text second. If nobody acknowledges within the window you set (for example, 5 minutes), page the backup person. Write the backup into the on-call schedule.

Agent instructions to paste into the tool that answers your calls:

You answer after-hours calls for [company].
Before anything else, check the caller's words against the Safety Word List.
If any listed word or phrase matches: play the approved safety message exactly as written, send the safety page to the on-call person, and do not book, quote, diagnose or reassure.
If nothing matches: take the caller's name, number, address and problem, and pass it to the on-call person, who decides what happens next.
Never decide on your own that a call is or isn't an emergency.

What to watch out for

• The caller is still inside. The message says to leave first. Don't let the agent collect an address before it plays the message.
• Local rules differ. Some utilities want you to call them directly; use the instructions your utility publishes for your area.
• Testing. Once a month, call your own line after hours and say "I smell gas". Check that the message plays word for word and the page arrives.
• Silent pages. Pages that land on a phone set to do-not-disturb don't work. Use a channel that rings through.

How to tell it's working

Keep a log of every safety match: time, matched words, whether the message played, and how long until the on-call person acknowledged. Review it weekly with the service manager. A week with zero matches still gets its test call. For how this fits with the rest of your call handling, see how Cortex puts a person in charge of every decision an agent hands off, or start with your free AI Operations Audit.