What happens step by step when a serious injury occurs and the emergency action plan is activated?

Q: What happens step by step when a serious injury occurs and the emergency action plan is activated?

From the Hockey Canada Emergency Action Plan flow chart: Player down: the safety person proceeds to the ice. The safety person (charge person) initially takes control of the situation, tells the player to lie still and tells bystanders such as other players not to move the player. Do not move the player. Assess whether an ambulance or medical care is required. Serious injury: activate the EAP by giving your pre-determined signal to the call person, control person and pre-determined first aid or medical person. Call person: calls 911 immediately (landline or cell phone), stays on the line with dispatch, and goes to the injured player. The call person sends a pre-determined person to the injured player to get more information and bring it to the phone, and returns to the player once dispatch has the information needed. The call person then stays with the safety person and injured player in case the condition changes. Control person: goes to ice level and opens the gate by the ice surface. If the AED or first aid kit is needed, the control person retrieves it and brings it to the player. The control person works with arena staff to clear the area for EMS, goes outside to wait for the ambulance and directs EMS to the injured player, and relays information to parents, coaches and others. EMS arrives and takes over player care. If the safety person lacks first aid or AED training, the pre-determined person with that training goes to the player when the call person is signalled to implement the EAP. Game officials: the game official remains in charge of the overall environment. If the safety person signals for help, several pre-determined people may respond and need access to the ice. Once the ambulance is called, the officials should send both teams to their dressing rooms. Source: https://cdn.hockeycanada.ca/hockey-canada/Hockey-Programs/Safety/Safety-Program/Downloads/eap_organization_form_e.pdf

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Accepted Answer

From the Hockey Canada Emergency Action Plan flow chart:

Player down: the safety person proceeds to the ice. The safety person (charge person) initially takes control of the situation, tells the player to lie still and tells bystanders such as other players not to move the player. Do not move the player. Assess whether an ambulance or medical care is required.
Serious injury: activate the EAP by giving your pre-determined signal to the call person, control person and pre-determined first aid or medical person.
Call person: calls 911 immediately (landline or cell phone), stays on the line with dispatch, and goes to the injured player. The call person sends a pre-determined person to the injured player to get more information and bring it to the phone, and returns to the player once dispatch has the information needed. The call person then stays with the safety person and injured player in case the condition changes.
Control person: goes to ice level and opens the gate by the ice surface. If the AED or first aid kit is needed, the control person retrieves it and brings it to the player. The control person works with arena staff to clear the area for EMS, goes outside to wait for the ambulance and directs EMS to the injured player, and relays information to parents, coaches and others.
EMS arrives and takes over player care.

If the safety person lacks first aid or AED training, the pre-determined person with that training goes to the player when the call person is signalled to implement the EAP.

Game officials: the game official remains in charge of the overall environment. If the safety person signals for help, several pre-determined people may respond and need access to the ice. Once the ambulance is called, the officials should send both teams to their dressing rooms.

Source: https://cdn.hockeycanada.ca/hockey-canada/Hockey-Programs/Safety/Safety-Program/Downloads/eap_organization_form_e.pdf