Fatal
Serious
Slight
Uncategorised
| Date | Local Authority | Vehicles | Casualties | Severity |
|---|---|---|---|---|
| Tue 2 Jan 1990 | Stevenage | 2 | 1 | Slight |
| Mon 8 Jan 1990 | Stevenage | 3 | 1 | Slight |
| Wed 10 Jan 1990 | North Hertfordshire | 2 | 1 | Slight |
| Sat 13 Jan 1990 | Stevenage | 1 | 1 | Slight |
| Sat 13 Jan 1990 | Stevenage | 4 | 3 | Serious |
| Mon 22 Jan 1990 | Stevenage | 3 | 1 | Serious |
| Sat 3 Feb 1990 | Stevenage | 1 | 1 | Fatal |
| Wed 7 Feb 1990 | East Hertfordshire | 2 | 1 | Slight |
| Thu 8 Feb 1990 | Stevenage | 2 | 2 | Slight |
| Thu 8 Feb 1990 | Stevenage | 2 | 2 | Slight |
| Sun 11 Feb 1990 | Stevenage | 1 | 1 | Slight |
| Fri 16 Feb 1990 | East Hertfordshire | 4 | 1 | Slight |
| Sat 17 Feb 1990 | Stevenage | 2 | 1 | Slight |
| Sun 18 Feb 1990 | Stevenage | 2 | 2 | Slight |
| Mon 19 Feb 1990 | North Hertfordshire | 2 | 1 | Slight |
| Thu 1 Mar 1990 | Stevenage | 2 | 1 | Slight |
| Fri 16 Mar 1990 | North Hertfordshire | 2 | 1 | Slight |
| Tue 20 Mar 1990 | Stevenage | 3 | 1 | Slight |
| Thu 22 Mar 1990 | Stevenage | 2 | 1 | Slight |
| Thu 22 Mar 1990 | Stevenage | 2 | 1 | Slight |
| Sat 24 Mar 1990 | Stevenage | 1 | 1 | Slight |
| Wed 28 Mar 1990 | North Hertfordshire | 3 | 5 | Serious |
| Mon 2 Apr 1990 | East Hertfordshire | 2 | 1 | Slight |
| Tue 3 Apr 1990 | Stevenage | 1 | 1 | Slight |
| Fri 6 Apr 1990 | East Hertfordshire | 3 | 1 | Slight |
| Mon 9 Apr 1990 | East Hertfordshire | 2 | 1 | Serious |
| Sat 21 Apr 1990 | Stevenage | 2 | 2 | Slight |
| Tue 1 May 1990 | Stevenage | 2 | 1 | Slight |
| Wed 2 May 1990 | Stevenage | 1 | 1 | Slight |
| Fri 4 May 1990 | Stevenage | 3 | 1 | Slight |
| Mon 7 May 1990 | East Hertfordshire | 1 | 1 | Serious |
| Fri 18 May 1990 | Stevenage | 1 | 1 | Serious |
| Sat 19 May 1990 | Stevenage | 2 | 1 | Serious |
| Sat 19 May 1990 | Stevenage | 2 | 3 | Slight |
| Tue 22 May 1990 | East Hertfordshire | 3 | 2 | Slight |
| Sat 26 May 1990 | North Hertfordshire | 2 | 2 | Serious |
| Sun 27 May 1990 | North Hertfordshire | 2 | 3 | Slight |
| Sat 2 Jun 1990 | Stevenage | 1 | 1 | Slight |
| Thu 7 Jun 1990 | Stevenage | 2 | 1 | Slight |
| Thu 7 Jun 1990 | North Hertfordshire | 2 | 1 | Serious |
| Sat 9 Jun 1990 | East Hertfordshire | 2 | 1 | Slight |
| Tue 12 Jun 1990 | North Hertfordshire | 3 | 2 | Slight |
| Wed 13 Jun 1990 | Stevenage | 2 | 1 | Slight |
| Fri 15 Jun 1990 | North Hertfordshire | 2 | 1 | Serious |
| Sun 17 Jun 1990 | North Hertfordshire | 2 | 1 | Slight |
| Wed 20 Jun 1990 | North Hertfordshire | 2 | 1 | Slight |
| Fri 22 Jun 1990 | Stevenage | 1 | 1 | Slight |
| Fri 22 Jun 1990 | Stevenage | 2 | 1 | Slight |
| Sat 23 Jun 1990 | Stevenage | 2 | 2 | Serious |
| Tue 26 Jun 1990 | Stevenage | 2 | 1 | Slight |
| Sat 30 Jun 1990 | North Hertfordshire | 2 | 2 | Slight |
| Wed 11 Jul 1990 | Stevenage | 2 | 1 | Slight |
| Tue 17 Jul 1990 | Stevenage | 1 | 1 | Fatal |
| Tue 24 Jul 1990 | East Hertfordshire | 2 | 2 | Slight |
| Tue 31 Jul 1990 | Stevenage | 1 | 2 | Slight |
| Sat 4 Aug 1990 | Stevenage | 2 | 1 | Slight |
| Mon 6 Aug 1990 | North Hertfordshire | 2 | 1 | Slight |
| Mon 13 Aug 1990 | East Hertfordshire | 2 | 1 | Serious |
| Wed 15 Aug 1990 | Stevenage | 2 | 2 | Slight |
| Tue 28 Aug 1990 | North Hertfordshire | 2 | 1 | Slight |
| Thu 30 Aug 1990 | Stevenage | 2 | 1 | Slight |
| Mon 10 Sep 1990 | East Hertfordshire | 3 | 2 | Slight |
| Tue 11 Sep 1990 | Stevenage | 2 | 1 | Slight |
| Thu 13 Sep 1990 | Stevenage | 2 | 1 | Slight |
| Thu 13 Sep 1990 | East Hertfordshire | 2 | 1 | Slight |
| Fri 14 Sep 1990 | Stevenage | 3 | 1 | Slight |
| Sat 15 Sep 1990 | Tameside | 2 | 2 | Slight |
| Sat 22 Sep 1990 | North Hertfordshire | 3 | 3 | Slight |
| Wed 26 Sep 1990 | North Hertfordshire | 2 | 1 | Slight |
| Sat 29 Sep 1990 | North Hertfordshire | 2 | 1 | Slight |
| Wed 3 Oct 1990 | Stevenage | 2 | 1 | Slight |
| Sat 6 Oct 1990 | Stevenage | 3 | 4 | Serious |
| Wed 10 Oct 1990 | Stevenage | 2 | 1 | Slight |
| Fri 12 Oct 1990 | Stevenage | 1 | 1 | Slight |
| Fri 12 Oct 1990 | Stevenage | 2 | 1 | Slight |
| Wed 17 Oct 1990 | North Hertfordshire | 2 | 1 | Slight |
| Tue 23 Oct 1990 | Stevenage | 2 | 1 | Slight |
| Fri 9 Nov 1990 | Stevenage | 2 | 2 | Slight |
| Sun 25 Nov 1990 | Stevenage | 3 | 1 | Slight |
| Sun 2 Dec 1990 | Stevenage | 1 | 2 | Slight |
| Tue 4 Dec 1990 | North Hertfordshire | 2 | 1 | Slight |
| Tue 4 Dec 1990 | Stevenage | 2 | 1 | Slight |
| Tue 4 Dec 1990 | Stevenage | 2 | 1 | Slight |
| Wed 12 Dec 1990 | Stevenage | 2 | 1 | Slight |
| Sat 15 Dec 1990 | Stevenage | 1 | 1 | Slight |
| Mon 17 Dec 1990 | Stevenage | 2 | 2 | Slight |
| Wed 19 Dec 1990 | Stevenage | 2 | 1 | Serious |
| Wed 19 Dec 1990 | Stevenage | 2 | 1 | Slight |
| Wed 19 Dec 1990 | Stevenage | 2 | 1 | Slight |
| Wed 26 Dec 1990 | Stevenage | 2 | 1 | Slight |
| Fri 28 Dec 1990 | Stevenage | 2 | 1 | Slight |