Transporting dangerous goods: ADR tunnel categories
Updated 7 April 2025
ADR聽tunnel categories
Tunnels in Great Britain are given a category from A to E to control the transport of dangerous goods through them.
Category A tunnels are considered low risk which means there are no restrictions when transporting dangerous goods through them.
Category E marked tunnels are considered to be high risk, which means very few dangerous goods are allowed to be transported through them.
| Tunnel | Category |
|---|---|
| Blackwall | E |
| Clyde | D |
| Dartford | C |
| East India Dock Road | E |
| Heathrow Airport | Category E between 0400 and 2300 Category C all other times |
| Limehouse | E |
| Mersey | D |
| Rotherhithe | E |
| Silvertown | E |
| Tyne | C |
Understanding ADR tunnel categories
The table below displays each tunnel code and whether they are restrictive or not.
| Tunnel category | Risk level | Restrictions |
|---|---|---|
| A | Low risk | No restrictions |
| B | Limited risk | Few restrictions |
| C | Medium risk | Some restrictions |
| D | High risk | Many restrictions occur |
| E | Very high risk | Restricted tunnel |
For more information about transporting dangerous goods through different categories of tunnels, see the聽.