Better reference to ISA 18.2

docs/source/dev_manual.rst

@@ -131,7 +131,7 @@ Grafana exposes its metrics to Prometheus, and thus can be used to query itself.
 Alerta
 -------------------------------------------
 
-The Alerta stack manages alerts that come from Grafana, and allows an operator to track them using the `ISA 18.2 <https://www.isa.org/getmedia/55b4210e-6cb2-4de4-89f8-2b5b6b46d954/PAS-Understanding-ISA-18-2.pdf>`_ alarm model, providing the following key `states <https://github.com/alerta/alerta/blob/master/alerta/models/alarms/isa_18_2.py>`_:
+The Alerta stack manages alerts that come from Grafana, and allows an operator to track them using the `ISA 18.2 <http://www.tc.faa.gov/its/worldpac/Standards/isa/ISA_18.2[1].pdf>`_ alarm model, providing the following key `states <https://github.com/alerta/alerta/blob/master/alerta/models/alarms/isa_18_2.py>`_:
 
 * ``NORM``: Condition is normal: alarm is not active, all past alarms were acknowledged,
 * ``UNACK``: Alarm is active, and has not been acknowledged,

docs/source/intro.rst

@@ -4,7 +4,7 @@ Introduction
 The Operations Central Monitoring setup collects monitoring information from across the instrument, and provides monitoring dashboards as well as an alarm-management system on top. It provides you with the following user services:
 
 * A *Grafana* monitoring & alerting system, exposed on http://localhost:3001 (credentials: admin/admin),
-* A *Alerta* alarm-management system, exposed on http://localhost:8081 (credentials: admin/alerta).
+* A *Alerta* alarm-management system implementing the `ISA 18.2 <http://www.tc.faa.gov/its/worldpac/Standards/isa/ISA_18.2[1].pdf>`_ alarm model, exposed on http://localhost:8081 (credentials: admin/alerta).
 
 As well as the following backing services to support the setup: