Fatal
Serious
Slight
Uncategorised
| Date | Local Authority | Vehicles | Casualties | Severity |
|---|---|---|---|---|
| Mon 15 Jan 1990 | North Hertfordshire | 2 | 1 | Slight |
| Tue 23 Jan 1990 | North Hertfordshire | 2 | 1 | Slight |
| Thu 25 Jan 1990 | North Hertfordshire | 1 | 1 | Slight |
| Sat 3 Feb 1990 | North Hertfordshire | 1 | 1 | Slight |
| Thu 8 Feb 1990 | North Hertfordshire | 2 | 1 | Slight |
| Sat 10 Feb 1990 | North Hertfordshire | 1 | 1 | Serious |
| Wed 21 Feb 1990 | North Hertfordshire | 1 | 1 | Slight |
| Mon 5 Mar 1990 | North Hertfordshire | 1 | 1 | Slight |
| Sat 10 Mar 1990 | North Hertfordshire | 1 | 2 | Slight |
| Mon 12 Mar 1990 | North Hertfordshire | 2 | 1 | Serious |
| Fri 30 Mar 1990 | Welwyn Hatfield | 2 | 4 | Serious |
| Mon 2 Apr 1990 | North Hertfordshire | 1 | 1 | Slight |
| Sat 7 Apr 1990 | North Hertfordshire | 2 | 3 | Slight |
| Sat 7 Apr 1990 | North Hertfordshire | 2 | 1 | Serious |
| Sun 8 Apr 1990 | North Hertfordshire | 1 | 1 | Serious |
| Tue 10 Apr 1990 | North Hertfordshire | 1 | 1 | Slight |
| Tue 10 Apr 1990 | North Hertfordshire | 1 | 1 | Slight |
| Thu 12 Apr 1990 | North Hertfordshire | 2 | 1 | Fatal |
| Tue 22 May 1990 | North Hertfordshire | 3 | 1 | Serious |
| Fri 22 Jun 1990 | North Hertfordshire | 2 | 1 | Serious |
| Thu 5 Jul 1990 | North Hertfordshire | 2 | 2 | Slight |
| Fri 13 Jul 1990 | North Hertfordshire | 1 | 1 | Serious |
| Wed 1 Aug 1990 | North Hertfordshire | 2 | 1 | Serious |
| Wed 1 Aug 1990 | Welwyn Hatfield | 2 | 1 | Slight |
| Thu 9 Aug 1990 | North Hertfordshire | 2 | 1 | Serious |
| Wed 15 Aug 1990 | North Hertfordshire | 1 | 1 | Slight |
| Sat 18 Aug 1990 | North Hertfordshire | 1 | 1 | Slight |
| Tue 28 Aug 1990 | North Hertfordshire | 1 | 1 | Serious |
| Wed 26 Sep 1990 | North Hertfordshire | 2 | 1 | Slight |
| Tue 2 Oct 1990 | North Hertfordshire | 2 | 1 | Slight |
| Wed 3 Oct 1990 | North Hertfordshire | 1 | 2 | Serious |
| Wed 3 Oct 1990 | North Hertfordshire | 2 | 1 | Slight |
| Wed 17 Oct 1990 | North Hertfordshire | 2 | 1 | Slight |
| Sat 27 Oct 1990 | North Hertfordshire | 3 | 1 | Serious |
| Fri 2 Nov 1990 | North Hertfordshire | 3 | 4 | Slight |
| Fri 2 Nov 1990 | North Hertfordshire | 1 | 1 | Slight |
| Sat 10 Nov 1990 | North Hertfordshire | 1 | 1 | Slight |
| Sat 10 Nov 1990 | North Hertfordshire | 2 | 1 | Slight |
| Sun 11 Nov 1990 | North Hertfordshire | 2 | 2 | Slight |
| Fri 16 Nov 1990 | North Hertfordshire | 2 | 1 | Slight |
| Wed 5 Dec 1990 | North Hertfordshire | 1 | 1 | Serious |
| Wed 12 Dec 1990 | North Hertfordshire | 1 | 1 | Serious |
| Fri 14 Dec 1990 | North Hertfordshire | 2 | 1 | Serious |