Fatal
Serious
Slight
Uncategorised
| Date | Local Authority | Vehicles | Casualties | Severity |
|---|---|---|---|---|
| Sat 12 Jan 1991 | Welwyn Hatfield | 2 | 1 | Serious |
| Fri 18 Jan 1991 | Welwyn Hatfield | 2 | 3 | Slight |
| Sat 26 Jan 1991 | Welwyn Hatfield | 1 | 1 | Slight |
| Mon 4 Feb 1991 | Welwyn Hatfield | 1 | 1 | Slight |
| Tue 5 Feb 1991 | Stevenage | 2 | 1 | Serious |
| Sat 9 Feb 1991 | North Hertfordshire | 1 | 2 | Slight |
| Wed 13 Mar 1991 | Hertsmere | 2 | 1 | Serious |
| Sat 23 Mar 1991 | Welwyn Hatfield | 1 | 1 | Slight |
| Tue 26 Mar 1991 | North Hertfordshire | 2 | 1 | Slight |
| Mon 8 Apr 1991 | North Hertfordshire | 2 | 1 | Slight |
| Mon 8 Apr 1991 | Welwyn Hatfield | 2 | 1 | Serious |
| Tue 16 Apr 1991 | North Hertfordshire | 2 | 1 | Slight |
| Thu 18 Apr 1991 | North Hertfordshire | 2 | 2 | Slight |
| Thu 2 May 1991 | North Hertfordshire | 2 | 1 | Slight |
| Fri 3 May 1991 | Welwyn Hatfield | 2 | 2 | Slight |
| Thu 9 May 1991 | North Hertfordshire | 3 | 1 | Serious |
| Thu 23 May 1991 | Stevenage | 1 | 1 | Slight |
| Thu 23 May 1991 | North Hertfordshire | 1 | 1 | Slight |
| Thu 23 May 1991 | Welwyn Hatfield | 4 | 2 | Slight |
| Thu 30 May 1991 | Stevenage | 1 | 1 | Slight |
| Fri 14 Jun 1991 | Stevenage | 2 | 1 | Slight |
| Fri 14 Jun 1991 | Welwyn Hatfield | 1 | 1 | Slight |
| Fri 21 Jun 1991 | North Hertfordshire | 2 | 5 | Serious |
| Sun 23 Jun 1991 | Welwyn Hatfield | 2 | 1 | Slight |
| Mon 1 Jul 1991 | Welwyn Hatfield | 2 | 1 | Slight |
| Fri 5 Jul 1991 | Stevenage | 2 | 1 | Slight |
| Fri 12 Jul 1991 | Welwyn Hatfield | 2 | 3 | Slight |
| Wed 17 Jul 1991 | North Hertfordshire | 1 | 1 | Slight |
| Thu 18 Jul 1991 | Welwyn Hatfield | 1 | 1 | Slight |
| Fri 19 Jul 1991 | Stevenage | 2 | 2 | Slight |
| Tue 13 Aug 1991 | North Hertfordshire | 2 | 1 | Serious |
| Mon 19 Aug 1991 | Welwyn Hatfield | 2 | 1 | Slight |
| Thu 12 Sep 1991 | Stevenage | 2 | 1 | Slight |
| Thu 12 Sep 1991 | North Hertfordshire | 3 | 1 | Slight |
| Tue 17 Sep 1991 | Welwyn Hatfield | 2 | 1 | Slight |
| Wed 18 Sep 1991 | Welwyn Hatfield | 2 | 1 | Slight |
| Mon 23 Sep 1991 | Welwyn Hatfield | 2 | 1 | Slight |
| Mon 23 Sep 1991 | Welwyn Hatfield | 2 | 1 | Slight |
| Wed 2 Oct 1991 | Stevenage | 1 | 1 | Slight |
| Thu 3 Oct 1991 | North Hertfordshire | 2 | 1 | Slight |
| Thu 3 Oct 1991 | North Hertfordshire | 2 | 1 | Slight |
| Fri 4 Oct 1991 | Stevenage | 2 | 1 | Serious |
| Fri 4 Oct 1991 | Stevenage | 2 | 1 | Serious |
| Fri 18 Oct 1991 | North Hertfordshire | 2 | 3 | Slight |
| Fri 18 Oct 1991 | North Hertfordshire | 2 | 3 | Slight |
| Mon 11 Nov 1991 | Welwyn Hatfield | 2 | 1 | Slight |
| Sat 7 Dec 1991 | Stevenage | 2 | 1 | Slight |
| Sat 7 Dec 1991 | North Hertfordshire | 2 | 1 | Slight |
| Fri 20 Dec 1991 | North Hertfordshire | 3 | 1 | Serious |
| Tue 24 Dec 1991 | Welwyn Hatfield | 2 | 2 | Slight |