Placardset
Step by step

How to use the Emergency Response Guidebook

Find the material's four digit ID number, look it up in the yellow section to get a three digit guide number, and check whether the entry is highlighted in green. If it is green and nothing is burning, read Table 1 for the isolation and protective action distances; if it is not, use the orange guide's immediate precautionary distance. Then read the orange guide for what to do first.

The steps

  1. Stay back. Approach from upwind, uphill or upstream, keep people away, and do not walk into a spill, vapor or smoke while you read placards from a distance.
  2. Identify the material. Look for the four digit ID number on a placard, an orange panel or the shipping paper. If there is no number, use the name from the shipping paper; if there is neither, use the placard.
  3. Find the guide number. Look the ID number up in the yellow section, or the name in the blue section. With only a placard, use the placard table on printed pages 8 and 9. With nothing at all, use Guide 111.
  4. Check the green highlight. If the entry is highlighted in green and there is no fire, go to Table 1 for the initial isolation and protective action distances, and still read the guide.
  5. Read the orange guide. Turn to the guide number. Its left page gives the hazards, public safety and evacuation, including the immediate precautionary isolation distance; its right page gives fire, spill and first aid.
  6. Call for help. Call 911 or your local number, then the emergency response telephone number on the shipping paper, and report what you found.

Worked example: a chlorine leak at night

A cylinder on a flatbed is leaking slowly from a cracked valve. It is night. An orange panel on the truck reads 1017. Here is the path through the 2024 guidebook, exactly as the daily drill grades it.

  1. The ID number is known, so the yellow section is the right tool. On printed page 29, 1017 is Chlorine, Guide 124.
  2. The row is highlighted in green, and nothing is burning, so the distances come from Table 1, not from the guide.
  3. A leak from one cylinder is a small spill: a small package, or a small leak from a large one. Table 1, small spill: isolate 60 m in all directions, then protect 1.5 km downwind at night. In feet and miles: Table 1, small spill: isolate 200 ft in all directions, then protect 0.9 mi downwind at night.
  4. Had the whole tank been open, the large spill columns apply, and for chlorine they do not give a number: Table 1 says "Refer to Table 3" for a large spill of Chlorine.
  5. Guide 124 then gives the first actions: stay upwind and out of low areas, keep combustibles away, and water only on any fire.

When you have a name but no number

The blue section lists the same entries by name in alphabetical order, with the guide number and the ID number beside each one. It is the way in when a shipping paper or a package label gives a name you can read but the number is hidden or damaged. The two sections carry the same 2,771 entries; the only difference is the order.

When all you have is a placard

The placard table on printed pages 8 and 9 gives one guide per placard design, for use only when neither the number nor the name is known. It is a starting point, not an answer. A class 3 FLAMMABLE placard points to Guide 127; the moment the number turns out to be 1203, the yellow section sends you to Guide 128 instead. If nothing can be identified, or the DANGEROUS placard is shown on a mixed load, the table points to Guide 111.

Common mistakes

Practise it

The daily drill gives five scenarios like this one every day, and the UN number lookup lets you check any number. For the distances in detail, read isolation and protective action distances.

Sources

Checked on 27 September 2026. Everything here is said in our own words; the guidebook's text is paraphrased, never quoted at length. Where your instructor, your employer's plan or the current printed guidebook says something different, follow them.

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Frequently asked questions

What if more than one hazardous material is involved?

The guidebook's own flowchart says not to use it in that case: call the emergency response number on the shipping paper or the numbers in the back of the book.

What does the P after a guide number mean?

That the material may polymerize violently under some conditions, such as heat or contamination. The guide page is the same number without the P.

Should I use Table 1 if the material is on fire?

No. With a fire, the orange guide's evacuation distance comes first; Table 1 is then used downwind for any material still being released.

Does the placard table give the same guide as the ID number?

Not always. The placard table gives a general guide for the class, and the ID number gives the specific one. When the ID number is known, it wins.